Diagnosis is confirmed by microscopic examination of skin scrapings.
8. Tinea circinata
presents with round fungal lesions on the face and leg with normal sensation.
9. Pityriasis rosea
oval shaped lesions generally only on the trunk. Lesions are normally not itchy and sensation,
sweating and peripheral nerves are all normal.
presents with an initial ‘herald lesion’ followed several weeks later by numerous
10. Seborrhoeic dermatitis
is normal and lesions are common on the trunk and may coalesce into larger patches.
lesions are yellow coloured, itchy and show coarse scaling. Sensation
11. Annular psoriasis
is characterized by the presence of grey scaly figurate lesions that usually
exhibit a symmetrical distribution. There may be pustules or pitting of the nails.
12. Lichen planus
lesions.
presents with skin papules that may coalesce into larger patches or annular
13. Granuloma annulare
presents with round ring-like symptomless papules or nodules.
14. Pityriasis alba
is a mild eczematous condition which leaves slightly scaling hypopigmented
macules with an ill-defined border. It can be difficult to distinguish from early leprosy disease.
15. Discoid eczema
presents as discrete well-defined coin shaped patches of eczema on the skin.
Usually the pattern of the lesions is symmetrical and they are very itchy.
16. Fixed drug eruptions
are more erythematous and infiltrated. Lesions subside after the withdrawal of the causative
show well defined violaceous macules. In the active stage the lesions
drug and reappear rapidly at the same site with re-administration of the drug.
Less commonly occurring conditions
1. Systemic lupus erythematosus (SLE)
lesions of lupus erythematosus discoides, necrobiosis lipoidica (check for hyperglycaemia) and
may be taken for leprosy. Ring-like skin and mucosal
of porphyria cutanea tarda (lesions chiefly on the hands and face, where exposed to the light)
may pose diagnostic problems.
2. Sarcoidosis
tuberculoid leprosy. They can be differentiated by absence of loss of sensation.
may show annular lesions, some times polycyclic, which may closely resemble
3. Neurofibromatosis (Von Recklinghausen’s disease)
has numerous café au lait patches that
may be confused with leprosy. In neurofibromatosis Type 1 all children have these patches
before 2 years old and 70% have freckles in the axillae. Nearly all also have hamartomas in the
iris (Lisch’s nodules) and develop neurofibromas. In Type 2 caféau lait patches rarely occur
and freckles are absent.
4. Kaposi’s sarcoma lesions
and nodular. They can be found particularly in Aboriginal and African patients and mimic
lepromatous leprosy.
are often found on the foot or leg. Lesions are shiny, violaceous
5. Lupus vulgaris
plaques. Typically lupus vulgaris lesions are accompanied with ulceration and scarring.
(skin tuberculosis) shows brown-yellowish nodules that may coalesce into
6. Syphilis
often have a false positive VDRL screening test for syphilis.
infection may lead to a residual light coloured skin lesion. People with leprosy may
7. Diffuse cutaneous leishmaniasis
considered in immigrants from or travelers to regions with endemic leishmaniasis. In dermal
leishmaniasis however, eyebrows are not affected.
may closely mimic lepromatous leprosy and should be
8. Lymphoma
Causes of neuropathy should also be considered in those patients presenting with a peripheral
neuropathy. If assessment demonstrates diminished temperature and pain sensation, while sparing
may present with shiny nodular skin lesions. It occurs more commonly in males.
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Guidelines for the Control of Leprosy in the Northern Territory
vibration, position sense and deep tendon reflexes, which is very unusual,
primary amyloidosis
and
muscle wasting of the hand should also warrant the exclusion of leprosy as a diagnosis.
Of note, 2 conditions may co-exist, especially in tropical climates such as the NT. In particular
leprosy and fungal lesions may have a similar appearance, and can often occur together, especially
in tropical climates. If there is any doubt about the diagnosis a trial of antifungal treatment such
as selenium sulphide (Selsun) for tinea versicolor or miconazole for tinea corporis should be
commenced. The patient can be reviewed after 2 months of therapy to assess the response.
syringomyelia should be considered. Cases of peripheral neuropathy such as foot drop or
Treatment
MDT is the standard for the treatment of leprosy worldwide and was first introduced in 1982.
Research demonstrates that it is the key to achieving cure in the individual, reducing the rates of
drug resistance and breaking the cycle of transmission. Recommended regimens for treatment have
been based on those recommended in the WHO
the Disease Burden Due to Leprosy
Enhanced Global Strategy for further Reducing(2011-2015)5 but have included a 24 month treatment option
for cases with a high bacillary index. Consideration should be taken of the drug profiles (Appendix
4). It is recommended that if the classification of a case is in doubt, or the skin smear is positive,
that the patient be treated as having MB leprosy.
NT CDC leprosy treatment recommendations
Paucibacillary leprosy (PB)
NT CDC recommended treatment for those 15 years and above (Table 10)
1. Dapsone 100mg daily (self administered) plus rifampicin 600mg monthly for 6 months for all
types of paucibacillary (PB) leprosy including single lesion paucibacillary (SLPB) leprosy.
:
Single dose rifampicin, ofloxacin and minocycline (ROM) has been used in India, Bangladesh and
Brasil for PB leprosy, however a recent WHO sponsored Indian study
similar success rates in the complete clearance of PB leprosy, relapse rates over a 54 month
period were more than 2 times higher among patients treated with ROM as compared to WHO
PB standard MDT for those with 2 to 5 lesions. Therefore 6 months of PB treatment should be
given for all PB leprosy (Table 10).
Even for SLPB it is recommended that 6 months PB treatment be given as this is felt to be more
likely to achieve the highest and sustained cure rate.
21 demonstrated that despite22
Single once-off treatment with ROM for SLPB would be considered in the NT only in very isolated
locations where follow-up is deemed absolutely not possible or a patient is defaulting such that
continued follow-up and treatment became impossible.
Guidelines for the Control of Leprosy in the Northern Territory
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Table 10. NT first line MDT regimen with adult (≥15 years old) doses
PB including SLPB MB – Low BI <4+
MB – High BI ≥4+
Duration
6 months 12 months 24 months
Dapsone
100mg daily selfadministered
100mg daily selfadministered
100mg daily selfadministered
Rifampicin
600mg monthly* DOT# 600mg monthly* DOT# 600mg monthly* DOT#
Clofazimine
50mg daily selfadministered
plus
300mg monthly* DOT
-#
50mg daily self-administered
plus
300mg monthly* DOT
#
*
remember (on the same day of the week throughout the course)
In practice, 4-weekly dosing and review may be easier to implement for the health service and easier for the patient to
#
DOT, directly observed treatment, means dose ingestion is observed and recorded by a health worker
Multibacillary leprosy (MB)
NT CDC recommended treatment for those 15 years and above (Table 10):
1. Those with high BI should be treated for 24 months or until smear negative.
2. Low BI (<4+) MB leprosy patients should be adequately treated with 12 months treatment but
still require vigilant follow-up.
3. High BI (≥4+) MB leprosy patients should have treatment for at least 24 months until there is
more conclusive evidence of efficacy with the 12 month regimen.
Although the WHO currently recommends 12 months of treatment for all MB leprosy, the NT
recommendation for the present includes continuation for 24 months treatment for MB patients
with a BI of ≥4+. This is due to 90% of relapses being in MB patients with a BI of 4+ or greater
there being no long term relapse data available to support limiting MDT treatment to 12 months.
It should be noted also that patients with smears that remain positive following recommended
treatment have a higher leprosy relapse rate.
23 and
Ongoing leprosy treatment studies
A study in Brazil of the initial and the final BI of MB patients receiving either 12 or 24 months of
WHO MDT followed patients for 2 years and showed no significant difference in decline in the BI in
high and low BI groups and no significant difference in the frequency of reactions. The study was
however unable to evaluate the relapse occurrence and is due to continue follow-up for a further 5
years.
24
There are well-documented reports of persistence of disease or relapses even after 24 months of
treatment. Although most MB patients become smear negative after 24 months of treatment, some
high BI cases can take 5 to 6 years to become smear negative. Due to most relapses occurring 5
years post-treatment cessation, intensive surveillance, including of nerve impairment, is probably
required for 8 to 10 years to detect relapses in high bacterial load cases.
23
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Guidelines for the Control of Leprosy in the Northern Territory
Special case considerations
Treatment of children with leprosy
The WHO recommends fixed doses for children from 10-14 years. These doses are also
recommended for use in the NT in consultation with appropriate specialists (Table 11).
Table 11. WHO and NT recommended doses for 10-14 year old children
PB including SLPB MB - Low BI <4+
MB - High BI ≥4+
Duration
6 months 12 months 24 months
Dapsone
50mg daily selfadministered
50mg daily selfadministered
50mg daily selfadministered
Rifampicin
450mg monthly* DOT# 450mg monthly* DOT# 450mg monthly* DOT#
Clofazimine
50mg daily selfadministered
150mg monthly* DOT
-#
50mg daily selfadministered
150mg monthly* DOT
#
* In practice, 4-weekly dosing and review may be easier to implement for the health service and easier for the patient to
remember (on the same day of the week throughout the course)
#
DOT, directly observed treatment, means dose ingestion is observed and recorded by a health worker
Children, especially those under the age of 10 years, should with the assistance of expert specialist
advice, receive proportionately reduced doses of the above drugs to minimize adverse drug
reactions. Clofazimine is available only in a 50mg capsule formulation and smaller calculated daily
doses may be given for example as 50mg on alternate days, or 50mg twice a week.
Pregnancy
Leprosy is exacerbated during pregnancy and therefore continuation of patients on standard MDT is
essential. Precaution should be taken with regard to breast-feeding as the medications are excreted
in breast milk. There are however, no reports of any adverse effects except for mild-discoloration
of the infant due to clofazimine.
Co-existent leprosy with active TB disease
Screening for leprosy should be considered in all cases of active TB infection. Patients diagnosed
with both leprosy and TB require both full TB and leprosy treatment (see
of Tuberculosis in the Northern Territory
regimens and should be given in the dose required to treat TB. Second-line regimens for leprosy
Guidelines for the Control, 2008).25 Currently only rifampicin is common to both
that contain minocycline or ofloxacin may be necessary if there are severe side-effects caused by
a drug in the first-line regimens. Information about all drugs used is provided in Appendix 4.
Co-existent leprosy with latent tuberculosis infection (LTBI)
Leprosy treatment should be the priority however if LTBI is present and active TB is excluded then
LTBI can be opportunistically treated. Treatment completed with a MDT leprosy regimen containing
rifampicin daily for at least 4 months will prophylactically treat LTBI avoiding the requirement for
isoniazid treatment.
Guidelines for the Control of Leprosy in the Northern Territory
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Co-existent infection with human immunodeficiency virus (HIV)
The concern that HIV infection would increase susceptibility to leprosy has not been realised and
evidence suggests it does not alter the clinical features of leprosy. Patients may have co-infection
with leprosy and HIV and current evidence suggests that no modification is required of the standard
MDT for leprosy or the antiretroviral regimen for HIV management. Care of the patient should be by
specialists familiar with both diseases.
Unable or refusal to take rifampicin (adult)
PB leprosy:
a 6 month regimen consisting of daily administration of:
•
• 50mg clofazimine; together with 2 of the following drugs –
•
• 400mg ofloxacin, 100mg minocycline OR 500mg clarithromycin.
MB leprosy:
the above regimen followed by daily administration of
•
• 50mg clofazimine; together with
•
• 100mg minocycline OR 400mg ofloxacin.
All taken for an additional 18 months or until smear negative.
Unable or refusal to take clofazimine (adult)
MB leprosy:
clofazimine can be replaced by ofloxacin 400mg daily or by minocycline 100mg
daily.
Unable or refusal to take dapsone (adult)
PB leprosy:
clofazimine 50mg daily should be substituted for dapsone.
MB leprosy:
No further modification of the regimen is required.
Defaulters
Leprosy treatment defaulters represent a challenge to manage due to the requirement for many
months of treatment and for extended time period follow-up. Usage of the above treatment regimens
can be considered where refusal is of certain regimen medications.
Single dose ROM treatment in SLPB cases may be considered in persistent defaulters.
defaulter PB cases (non SLPB) single dose ROM treatment may be considered but is not ideal. For
MB cases every effort should be made to treat and follow-up the patient according to the treatment
21 In extreme
guidelines due to significant concerns regarding long-term relapses.
Treatment plan considerations
Pre-treatment investigations
1. FBE, UEC, LFT, hepatitis B and C and HIV serology
2. G6PD
3. Mantoux and CXR to exclude co-existent TB or LTBI (see p26).
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Guidelines for the Control of Leprosy in the Northern Territory
Follow-up consultations
1. Ophthalmology review
2. Photography of skin lesions (with consent)
3. Document BI of skin smears/biopsies
4. Discuss importance of medication adherence and the planned regimen
5. Discuss drug side-effects and when to report to medical staff
6. Discuss the need to seek medical advice about deteriorating nerve function
Case Holding
Medication should initially be dispensed weekly until full adherence with and understanding of the
regimen is assured, and then a 4-weekly cycle of DOT and examination is established. Failure
to attend a single 4-weekly DOT requires an immediate effort to trace the patient and find an
explanation.
Sometimes this situation arises because the patient is ill at home with a leprosy reaction, a drug
side effect, or intercurrent illness. The patient who suffers a leprosy reaction may lose confidence
in the treatment regimen unless it is carefully explained beforehand that this might occur, and does
not imply bacteriological worsening of the illness or failure of treatment.
For each case a local member of the health staff should be identified to accept responsibility for
providing medication, assessing adherence, monitoring nerve function, and tracing absentees - all
on a 4-weekly basis. Review should occur 3-monthly by a local medical officer, and 6-monthly by
TB/leprosy unit staff.
Adherence should be documented on the leprosy treatment card (see Appendix 5).
Completed Treatment
Completed treatment for a cure is defined as:
•
• MB leprosy (BI ≥4+) - 24 months of doses (or 24 x 4-weekly cycles) within 36 months.
•
• MB leprosy (BI <4+) - 12 months of doses (or 12 x 4-weekly cycles) within 18 months.
•
Those who do not adequately complete treatment need to be fully re-evaluated. Re-treatment
regimens will depend on clinical and bacteriological examination.
• PB leprosy – 6 months of doses (or 6 x 4-weekly cycles) within 9 months.
Prevention
The 2003 WHO ‘Final Push’ strategy for leprosy aimed to eliminate the disease as a condition of
public health importance worldwide. Prevention is also an essential aspect in the NT in particular in
moving towards disease elimination.
The strategy aims at preventing exposure to the disease. It can be approached through improving
education of health staff, environmental factors and by immunoprophylaxis of babies with BCG.
Guidelines for the Control of Leprosy in the Northern Territory
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Health education
Health staff need to be aware of the population of people who are at greatest risk of leprosy. This
includes the Aboriginal and migrant populations and specifically family and household contacts of
active cases of leprosy.
In addition, ongoing provision and updating of knowledge to health staff is needed to enable them
to diagnose patients with leprosy, provide ongoing care and management of patients and to form a
working relationship with the TB/Leprosy Unit.
This should be achieved through:
•
• The health worker curriculum
•
• Orientation of health and allied health staff
•
• Ongoing education sessions for health staff in the NT
Environmental factors
Leprosy has long been considered a ‘disease of poverty’ however there is little evidence confirming
the precise mechanisms through which poverty exerts its effects. One study from Malawi, showed
persons living in the worst standard of housing had double the risk of leprosy compared to those
living in the best category of dwelling.
14
Other diseases with respiratory transmission such as TB are associated with overcrowding and
overcrowding probably also increases the risk of acquiring leprosy. Advocacy to improve housing
quality, ventilation, water supply, and nutrition and to alleviate overcrowding, particularly in pockets
of relatively high incidence is considered vital for leprosy control.
Immunoprophylaxis
Bacille Calmette-Guérin (BCG) vaccine at birth
BCG vaccine has been widely used in the NT since 1960 and more than 90% of Aboriginal people
have been vaccinated. International trials have demonstrated a protective efficacy of BCG of
between 20% and 80%,
for TB) control strategy in the NT. The entire
vaccine trials have shown promise.
While a recent meta-analysis of 26 studies using BCG for control of leprosy
vaccination may enhance protection against leprosy, repeat BCG is not recommended in the NT.
The protection conferred by BCG appears greatest if the vaccine is administered before 15 years
of age. BCG offers greater protection against MB than PB leprosy.
The current policy in the NT is that BCG is recommended at birth for:
1. All Aboriginal neonates.
2. Non-Aboriginal neonates who will live in Aboriginal communities or in countries for more than 3
months with a high prevalence of tuberculosis.
3. Non-Aboriginal neonates born to mothers who have been treated for leprosy.
No booster is currently recommended.
26,27 and it is a recommended leprosy (and in certain population age groupsM. leprae genome has been sequenced and new28 supports that repeated
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Guidelines for the Control of Leprosy in the Northern Territory
High risk group screening
Opportunistic screening for leprosy by primary health care staff should be undertaken whenever
those people in high-risk groups present for medical care or examination.
The main high risk groups are Aboriginal and migrant populations. These populations are also the
high-risk groups for TB, so leprosy screening should be considered whenever screening for TB.
This includes:
1. TB school screening of 10 year olds (which targets migrant and Aboriginal children);
2. review of asylum seekers, newly resettled humanitarian migrants and detained fisherman;
3. review of patients on Immigration Department TB Health Undertakings (TBUs); and
4. community TB screening programmes.
Screening should include a full examination of the skin, including eyebrows, nerve examination
including an abnormalities in extremities due to denervation.
Contact tracing
Of all new leprosy cases in highly or moderately endemic areas, only around 30% have a history of
having been a household contact of a previous case.
where leprosy is now rare and there is a delay in presentation, as in the NT. One study has shown
that 95% of secondary cases occurred within 6 years of the diagnosis of the primary cases.
14 This percentage is likely to be much higher14
There are few health staff who have much experience with leprosy, so most need to be trained in
detecting the early signs and symptoms of leprosy. Patients who are suspected of having leprosy
should be reviewed by the most experienced local staff who will in turn liaise with the CDC TB/
Leprosy Unit.
How to go about leprosy screening
•
• Household, family, and close social contacts should be identified and examined for signs of
leprosy. Those at highest risk of disease are shared-bedroom contacts, and children who share
the household with the index case.
•
• Results should be documented in the local records, and the central leprosy database.
•
• New cases should be referred to the TB/leprosy Unit.
•
(Table 12).
• Contacts of MB cases need to be reviewed annually with a clinical examination for 6 years
•
to exclude disease, provided advice about symptoms and signs and a search for a source of
infection for the diagnosed PB case should be carried out.
• Contacts of PB cases are at lower risk of developing disease. They should be examined once
Guidelines for the Control of Leprosy in the Northern Territory
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Table 12. Follow-up of contacts of leprosy cases
Classification of the index
Years of annual CDC followup
after index diagnosis
PB – Including SLPB MB0* 6
Type of follow-up
Skin and nerve examination# Skin and nerve examination#
* Discharge if initial examination is negative
#
Perform VMT-ST or skin smear only if indicated by skin and nerve examination
Future prevention considerations
M. leprae
leprosy patients of developing disease varies according to the ‘closeness’ of the contact (bedroom,
household, neighbour, social), the type of index case (MB/PB) and the contact age.
In Malawi, being a household contact with a recent or past
increased risk of developing leprosy when compared with the general population.
48% slept in the same room, and their risk was 8-fold that of the non-contact individuals. However,
children aged between 5 and 9 years who shared a bedroom with an MB case had 37 times the
risk compared with children of the same age without contact with a MB case. For household and
bedroom contacts of
household contacts of MB cases, particularly children and those who have shared a bedroom with
the index case are the highest priority for followup and future consideration of prophylaxis.
transmission is considered to be via nasal secretions or skin. The risk to contacts ofMB case was associated with a 5-fold14 Of these contactsPB cases, the risk was 2 times as high as the non-contact group. Thus
Chemoprophylaxis
Medication given before the onset of disease to persons exposed to
A meta-analysis of 14 historic trials demonstrated that preventive treatment (using dapsone in 13
and rifampicin in 1) provided 60% protection against leprosy.
2 more recent studies using rifampicin as chemoprophylaxis.
The epidemiological study on contact transmission and chemoprophylaxis in leprosy (COLEP) has
looked at 21,000 contacts of 1037 newly diagnosed leprosy patients in Bangladesh between 2001
and 2007.
either a single dose of rifampicin or placebo.
M. leprae may prevent disease.29 Variable results have been shown in30 Contacts were divided into groups ie. close and distant contacts and were each given
The most recent findings show that the reduction in incidence after 2 years by a single dose of
rifampicin was 57%, and the protection was strongest among less high-risk contacts. The number
needed to treat to prevent a single case of leprosy among contacts was 265.
31
The Koninklijk Instituut voor de Tropen/Royal Tropical Institute (KIT) study
study carried out on 5 Indonesian islands with endemic leprosy between 2000 and 2003. There
were 3 distinct groups:
32 was an intervention
1. Control group
– no treatment
2. Contact group
– rifampicin given to contacts of leprosy patients
3. Blanket group
– rifampicin given to all persons.
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Guidelines for the Control of Leprosy in the Northern Territory
In total there were 3965 patients in the study and the yearly control incidence rate overall was 39
per 10,000. The cumulative incidence at 3 years was significantly lower in the blanket group where
everyone was given rifampicin. There was however no difference in incidence between the group
who had no treatment and the contact group who were given rifampicin. At 3 years further follow-up
(2003-2006), there was no difference between the 3 groups in terms of incidence.
32
Further studies need to the carried out with longer follow-up periods to ascertain the overall benefit
of rifampicin chemprophylaxis, but the evidence at this stage is not strong enough to recommend
rifampicin as chemoprophylaxis for leprosy contacts.
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Part 2. Nerve function impairment and lepra reactions
Classification of nerve function impairment (NFI)
Nerve function impairment (
NFI) is a clinically detectable loss of motor, sensory, or autonomic
peripheral nerve function.
Mycobacterium leprae is the only bacterial agent known to specifically
infect peripheral nerves. It is the resulting nerve function impairment (NFI) and associated deformities
and disability that has made leprosy such a feared disease. In field cohort studies 33-56% of
newly diagnosed patients have nerve damage
developed nerve damage during treatment.
silent neuropathy and Type 1 and Type 2 reactions.
33,34,35 and in a Bangladeshi study 25% of MB patients36,37 The main processes associated with NFI include
Silent neuropathy
NFI may occur in association with symptoms of neuritis (point pain and tenderness in nerve trunks,
or distal pain, hyperaesthesia and tingling in the sensory areas supplied by the nerve) or it may
occur insidiously without symptoms (termed ‘silent’ neuropathy).
of nerve function without any nerve pain, nerve tenderness, or symptoms of reaction.
to 86% of all NFI occurs silently,
by voluntary muscle testing - sensory testing (VMT-ST) whether or not the patient complains of
symptoms. When the directly observed component of MDT is administered monthly (or 4-weekly)
by a health worker, such an assessment should be performed.
Silent neuropathy is impairmentUp37,38 which mandates regular testing of motor and sensory function
Lepra reactions
Lepra reactions are immunologically mediated episodes of acute or subacute inflammation and
are classified as either Type 1 (reversal) reactions or Type 2 (erythema nodosum leprosum (ENL))
reactions (Table 11). They occur more commonly in MB leprosy than PB leprosy patients and in
patients who present initially with NFI.
39
Type 1
(reversal or upgrading) reactions are a delayed hypersensitivity response to M. leprae
antigens occurring in borderline lepromatous (BL), borderline (BB) or borderline tuberculoid (BT)
cases. They are characterised by acute neuritis and/or acutely inflamed skin lesions. Usually with
onset there is an associated change in Ridley-Jopling classification towards the tuberculoid end of
the spectrum. There is nerve tenderness with loss of sensory and motor functions. Redness and
swelling in pre-existing skin lesions occurs, and lesions which have not been visible may appear.
Fever, malaise and peripheral oedema are additional features if the reaction is severe. Onset may
be spontaneous though it is commonest after starting treatment.
Type 2
that develops due to an imbalance of the humoral immune system. They are the most serious
complication of leprosy and occur in about 15% of patients with multibacillary disease (LL and
BL).
(erythema nodosum leprosum or ENL) reactions are an immune complex response39 Reactions may occur spontaneously or while on treatment. There is a sudden appearance
of superficial or deep crops of new, tender, subcutaneous nodules on the back, the dorsum of the
hands or the extensor aspects of the forearms and thighs that generally last for about 3 days. The
whole episode usually lasts 2 weeks though may be prolonged or recurrent over several years.
ENL is commonly associated with systemic systems including:
•
• High fever peaking in the evenings
•
• Neuritis
•
• Leucocytosis
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Guidelines for the Control of Leprosy in the Northern Territory
•
• Orchitis
•
• Nephritis
•
•
• Periostitis including joint inflammation• Iridocyclitis (eye inflammation)
Type 1 and Type 2 reactions may coexist in a case of BL. The introduction of WHO-MB-MDT has
seen a reduction in the frequency and severity of ENL due to the anti-inflammatory effect of the
clofazimine component.
Table 13. Comparison of the features of Type 1 and Type 2 reactions
Type 1 Type 2
Classification
BT, BB, BL LL (occasionally BL, BB)
Immunology
immunity
Immune-complex deposition, elevated
TNF-alpha levels, dysfunctional cell
mediated immunity
Changing cell mediated
Classification change
Upgrading (usually) toward TT No change
Timing
First months of MDT May be years after treatment
Recurrent
Usually not Often
Duration
Several months 2 weeks
Sites of inflammation
soles, lymph nodes
The differential diagnosis of the skin lesions of Type 1 or Type 2 reactions is active leprosy (Table
14). In the context of drug resistance, leprosy may progress with the appearance of new lesions
despite MDT. Also, following the completion of treatment and apparent cure, new leprosy lesions
can be associated with a relapse (see p 46).
Nerves, skin lesions Skin nodules, iris, testes, joints, nerves,
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Table 14. Comparison of the features of new leprosy nodules and Type 2 reactions
New leprosy nodules Type 2 reaction
Onset
Gradual Sudden
Number
1 at a time Nodules appear in crops
Tenderness
- +
Bacterial Index
High in the nodule High or low
SFG reading*
Often solids Mainly granules
Resolution
weeks, with or without treatment
After months of MDT Successive waves of nodules subside after 2
* SFG, Solid-Fragmented-Granular reading - the proportions of solid, fragmented or granular appearing AFB in a skin smear. ‘Solids’ are
presumed to be viable bacilli; ‘Fragmented’ and ‘Granular’ are recently and remotely dead, respectively.
Disability grading
NFI and its secondary consequences are described in a ‘disability grading’ (0, 1, or 2) for the
purposes of reporting to WHO, and for monitoring program objectives. The highest value for any
body part is taken as the overall disability grading for the patient; eg. if hands, feet, and left eye are
graded 0, but the right eye is graded 2, then the overall grading for the patient is 2. It is sometimes
expressed as an Eye-Hand-Foot (EHF) score where each hand, foot, and eye is graded 0, 1 or 2,
and these grades are summed bilaterally for a maximum score of 12.
Table 15. WHO grading of leprosy related disability
1
Grading*
0
deformity or damage
No eye problems due to leprosy; no evidence of
visual loss
Hands and Feet EyesNo anaesthesia, no visible
1
visible deformity or damage
Anaesthesia present, but no#
2
present
Visible deformity or damage†
Severe visual impairment (visual acuity worse
than 6/60; unable to count fingers at 6 metres)
or lagophthalmos or iridocyclitis or corneal
opacities
* The highest value of the leprosy disability grade for any part is taken as the overall disability grading of the patient
# Includes muscle weakness
† Includes ulceration, shortening, disorganisation, stiffness, loss of part or all of the hand or foot
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Guidelines for the Control of Leprosy in the Northern Territory
However, disability grades or hand, foot, eye (HFE) scores are not sensitive enough to be useful
in monitoring the progress of subtle impairment in an
is required (Appendices 1 and 2), and together with the indications for prednisolone and other
therapies, decisions about the requirement for prednisolone therapy can be made.
individual patient. For this purpose the VMTST
Detection of neuropathy
Nerve conduction studies (NCS)
Advanced neuropathy is already present before signs and symptoms of NFI appear. Nerve
conduction studies are able to detect this neuropathy before it is clinically apparent. This is a time
consuming and uncomfortable procedure and should only be requested in consultation with the TB/
Leprosy Unit.
The indications are:
1. To assist (where necessary) in the diagnosis of a suspected leprosy case.
2. As soon as possible after diagnosis to establish a baseline assessment of the extent and
severity of nerve damage.
3. Ideally at yearly intervals while taking MDT.
4. When new symptoms of neuritis, or findings of NFI - appear after MDT completion.
Voluntary muscle test-sensory test (VMT-ST)
In between the sensitive assessments that NCS provide, a VMT-ST should be performed to detect
NFI as a baseline at diagnosis, monthly while on MDT, and at each review after release from
treatment for the prescribed durations of follow-up (see Table 18, p44). With practice (for both
health worker and the patient), this should take around 10 minutes to complete thoroughly. See
Appendix 1 for the method.
The advantage of a standardised form of documentation is that an examiner can make a direct
comparison with an earlier examination (even if performed by another person) in trying to assess
whether new NFI has occurred or not. Use of a ballpoint pen for sensory testing is not as sensitive
for protective light-touch thresholds as nylon monofilaments, but they are universally available when
the latter are not. With appropriate training, their use produces reliable results between different
observers.
Treatment of nerve function impairment (NFI) and lepra reactions
Nerve damage occurs before diagnosis, during and after drug treatment and may also occur as
silent neuropathy without signs of inflammation. Treatment of reactions is aimed at controlling
acute inflammation, reducing pain and reversing eye and nerve damage. During treatment for lepra
reactions MDT should be continued.
Clinical suspicion of reactional states should lead to urgent specialist review and advice
should be sought regarding anti-inflammatory and immunomodulating drugs due to the
potential for permanent disabilities.
decreased peripheral nerve function because of motor and sensory loss.
Disabilities are a consequence of neural damage with
Guidelines for the Control of Leprosy in the Northern Territory
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Many studies have reported beneficial responses of NFI in reactions and silent neuropathy with
prednisolone. Studies show that improvement occurs in 60-80% of patients with neuropathy, mostly
within the first 3 months of a course, especially within the first few days, but further gains can be
made at a slower rate for several more months.
40,41
Acute primary NFI (first attack and those less than 6 months in duration) have a better prognosis
with treatment than chronic or recurrent forms, but improvement may still be seen in up to 50% of
the latter episodes.
duration of NFI.
40,42 Variablility in response to corticosteroid treatment relates to severity and40,41
The major modes of action of corticosteroids are:
1. Reduction of oedema in nerves and skin (improvement may be seen within days because of
alleviation of raised intra-neural pressure and ischaemia).
2. Suppression of
M leprae-specific T-cell inflammation. In Type 1 reactions, serial skin biopsies
have shown a slow decrease in Th1*cytokines (interferon-gamma, interleukin-12, and inducible
nitric oxide synthase) and cellularity in lesions. BL patients however may still have considerable
inflammation in lesions at 180 days, despite a course of treatment.
3. Reduction of post-inflammatory scarring within lesions.
Indications for prednisolone
Table 16. Indications for prednisolone
1 Recent NFI at
diagnosis
At the time of diagnosis of leprosy, NFI is detected that the patient tells
you is <12 months old.
2 New NFI during
or after MDT
NFI with or without symptoms of neuritis or reaction, detected on a
monthly VMT-ST during treatment or on annual VMT-ST after MDT
completion that had not been recorded on the previous assessment.
This includes:
•
• new loss of sensation in 2 or more points on the sensory chart; and
•
• new weakness, paralysis or increasing lid gap on the motor record.
3 Type 1 reaction
diagnosis, start prednisolone with MDT.
Any degree of severity, with or without neuritis or new NFI. If present at
4 Type 2 reaction
Moderate or severe ENL (not mild), or, ENL with neuritis or new NFI.
5
Progressive
subclinical
neuropathy
Deteriorating nerve conduction studies where worsening NFI has not
been detected on VMT-ST.
NB.
digital shortening, or deteriorating vision are
Advancing secondary consequences of NFI, e.g. enlarging ulcer, worsening contracture, increased clawing,not alone an indication of worsening NFI or an indication for prednisolone
treatment. They may instead reflect old irreversible NFI that is being inadequately managed in terms of appropriate
footwear and self-care. However, coexisting new NFI should be excluded.
*
See page 8.
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Guidelines for the Control of Leprosy in the Northern Territory
Prednisolone regimens
There is no firm consensus about the optimum regimen of corticosteroids and no randomised
controlled trials have been reported comparing regimens of differing dose and duration. The WHO
recommends a standardised 12-week course for outpatient use for Type 1 reactions where therapy
is generally initiated by experienced leprosy field staff who are not doctors or nurses (prednisolone
40mg, 30mg, 20mg, 15mg, 10mg, and 5mg daily, in this order, each dose for 2 weeks). Some
have expressed concern that the doses may be insufficient to be maximally beneficial, and the
relatively short duration could allow recurrences of NFI.
Whenever prednisolone is being used
precautions (see p39) and prior screening for opportunistic infections must be carried out.
There is consensus about the general principles of treatment with prednisolone, which should
ideally be tailored to the response of the individual.
1. The starting dose should be 1mg/kg (60mg for adults) for a severe reaction with symptoms of
neuritis. For silent neuropathy or mild reactions, a dose of 40mg may be sufficient since rapid
symptom amelioration is not required. The initial dose in either situation can be increased if
symptoms or NFI fail to improve after 2 weeks.
2. When the symptoms are controlled and NFI improves, tapering can commence.
3. Dose reduction can occur at a rate equivalent to 5mg every 1 to 2 weeks. This may need to be
slowed or the dose increased again if symptoms recur or NFI deteriorates.
4. Generally, in Type 1 reactions, BL cases will require longer treatment than BT.
5. Change to alternate daily dosing will minimise the cushingoid effects of therapy, particularly
where prolonged courses are anticipated. This is appropriate when a daily dose of 20mg has
been attained.
6. Morning dosing is less suppressive of adrenal function than evening doses.
7. Once physiological values of corticosteroid have been reached (the equivalent of 7.5mg
prednisolone per day), tapering should occur slowly to allow recovery of the hypothalamicpituitary-
adrenal axis.
8. During and after cessation of a prolonged course of prednisolone, supplementary doses may
be required for up to 12 months in the event of serious injury, infection or operation. The patient
should be advised to specifically mention the course of prednisolone to future medical care
9. During reactions,
10. Adjuncts to prednisolone for neuritis symptoms are rest of the affected part (bed rest, sling, splint,
crutches) and local warmth and protection around the nerve with a cotton wool bandage.
11. A regimen that uses multiples of prednisolone 25mg tablets for as long as possible (rather than
5mg tablets) will reduce the overall number of tablets per dose and improve patient acceptability
(Table 17).
givers.continue MDT without interruption along with prednisolone.
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Table 17. Example of 9 month tapering course of prednisolone for Type 1 reaction in BL
leprosy
Week No. Number of prednisolone tablets Equivalent daily dose
25mg tablets 5mg tablets
1-2
2 OD* 50mg
3-4
1.5 OD 1 OD 42.5mg
5-6
1.5 OD 37.5mg
7-8
1 OD 1 OD 30mg
9-10
1 OD 25mg
11-14
1.5 AD# 18.75mg
15-18
1 AD 12.5mg
19-22
4 AD 10mg
23-26
3 AD 7.5mg
27-30
2 AD 5mg
31-34
1 AD 2.5mg
35-38
0.5 AD 1.25mg
* OD, once daily
# AD, alternate days. Transition to AD dosing may be done by gradually increasing to the dose shown on 1 day, and
tapering the dose on the alternate days to zero.
Precautions with prednisolone usage
1. Nerve abscess (requires surgery and appropriate referral prior to prednisolone use).
2. Untreated infections (TB, strongyloidiasis, amoebiasis, osteomyelitis, infected ulcers, scabies)
need to be referred to a specialist and treated prior to prednisolone use.*
Screening prior to the commencement of prednisolone
1. Mantoux test and chest x-ray for LTBI and active TB.
2. Stool microscopy and culture (1 specimen), and serology for
serology and stool are negative, no further action is required. If serology and/or stool are
positive, give a single dose of ivermectin 200mcg/kg, and recheck serology for a fall in titre and
stool for clearance of parasite.
3. Blood glucose, electrolytes, urea and creatinine, FBE, LFT, HIV antibody, hepatitis B and
melioidosis serology. Where tests are abnormal refer to physician, infectious diseases physician
or liver clinic doctors as appropriate.
4. Visual acuities and check history of glaucoma.
5. Pregnancy test in reproductive age females.
6. Bone density assessment in postmenopausal women and elderly men.
Strongyloides stercoralis. If
*Refer to
Territory.
Prevention of opportunistic infections in immunosuppressed patients in the tropical top end of the Northern43
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Guidelines for the Control of Leprosy in the Northern Territory
7. History or risk factors for peptic ulceration.
8. History of psychiatric disorders.
9. Blood pressure and cardiac examination.
10. Weight.
Precautions during prolonged treatment
1. Avoid live vaccines during and for 3 months after therapy.
2. Increase dose during acute stress (intercurrent illness, surgery), eg double maintenance
dose.
3. High calcium intake (1200mg/day); restrict sodium intake; add potassium supplements if
necessary.
Therapy complications and their management
Type 2 reactions (ENL) are less frequently complicated by neuritis and NFI than Type 1 reactions. In
LL, NFI may be largely secondary to bacillary infiltration rather than inflammation, and commencing
MDT alone may produce improvement. If ENL is mild and not accompanied by neuritis or new NFI,
bed rest and aspirin are recommended.
Moderate and severe attacks of ENL or ENL with neuritis should be treated with prednisolone.
The tendency for ENL to recur means the duration of treatment should be as short as possible to
avoid steroid-dependence (eg 2 to 8 weeks). Recurrent ENL requires an increase of the daily MDT
clofazimine dose to 300mg (not for longer than 3 months – see drug information in Appendix 4) to
allow prednisolone to be withdrawn. The clofazimine dose is then tapered over several months by
100mg increments to 100mg daily, which is maintained until the completion of MDT.
Iridocyclitis complicating ENL should be treated with corticosteroid eye-drops and a mydriatic and
reviewed by an ophthalmologist.
Thalidomide usage
Thalidomide (400mg daily) reduces TNF-alpha levels and increases CD8 T cell numbers in ENL
and is rapidly effective in severe and recurrent forms. It controls and prevents neuritis, relieves
pain and improves nerve function effectively. Thalidomide use allows a reduction in prednisolone
requirements to avoid steroid dependency and furthermore, studies have shown thalidomide to be
very effective as a monotherapy.
The WHO Expert Committee on Leprosy (1997) advised that thalidomide is the drug of choice for
steroid unresponsive ENL in males and for females of non-reproductive age under expert supervision
and with extreme caution due to the risk of teratogenicity in the first trimester of pregnancy.
In the United States of America and Brazil it is licensed for steroid dependant leprosy or when
steroids are contraindicated in men and women. It is licensed by the Australian Therapeutic Goods
Administration for the treatment of ENL
care only. Women should use double contraception and report immediately if there is a delay in
menstruation.
In the future, pentoxifylline (a xanthine derivative), may be considered as it has also demonstrated
44 though treatment should be under specialist hospital
efficacy in treating symptoms in a double blind RCT where its usage was compared to thalidomide.
It was effective in reducing limb oedema and systemic symptoms in 62% of patients,
45 however
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data and evaluation of pentoxifylline are still limited and therefore its use is not recommended.
Prevention of NFI, deformity and handicap
Early case detection of leprosy
An important indicator in assessing the quality of a leprosy control program is the proportion of
newly diagnosed cases who have Grade 2 disability. Programs with effective education strategies
to raise the awareness of leprosy among health workers and those at-risk in the community will
have a new case disability Grade 2 proportion of around 5%. Programs with late case detection
may have proportions in excess of 50%.
Having NFI at the time of diagnosis is a risk factor for a poor ultimate disability outcome (measured
by the HFE score 5 years after completion of MDT). Those who first develop impairment after
treatment commences have a better prognosis. Furthermore, patients who have longstanding NFI
at the time of diagnosis (NFI for longer than 6 months) have a 15-fold higher incidence of
episodes
furtherof acute NFI than those who do not.37
Early case detection of leprosy and treatment with MDT rapidly stops multiplication of
M. leprae.
Combined, these are the most important steps to prevent NFI.
Early detection and treatment of NFI
Effective and rapid management of lepra reactions is essential. It is imperative therefore that:
•
for treatment.
• Patients be taught to recognize early signs and symptoms of reactions and to report promptly
•
• Health workers are able to diagnose and treat reactions and refer patients when necessary.
•
determined by a central pharmacy.
The fact that the likelihood of full recovery of nerve function with prednisolone is much higher in
acute or recent NFI (<6 months duration) than in older NFI, coupled with the fact that up to 80% of
all NFI occurs imperceptibly (silent neuropathy), mandates a system of regular clinical screening
for NFI even though a patient is asymptomatic.
• Adequate stocks of prednisolone are available and means of accessing thalidomide quickly is
Self-care of established complications
Impairments such as anaesthesia, weakness, and loss of sweating may have been present for too
long to be reversible with prednisolone or other therapies when discovered. In 20 to 30% of acute
cases the impairments may simply be refractory to therapy. Self-care routines when supported
by access to appropriate medical, surgical and rehabilitation services can prevent the secondary
consequences of these impairments.
Management of complications
1. Dry skin
rubbing with emulsifying ointment or an oil based topical preparation.
due to lack of sensation and should be treated by soaking in water, followed by
2. Ulceration and fissures
osteomyelitis if not managed early, and loss of digits or limbs can result. These should be
covered to allow them to heal.
(due to loss of protective sensation) lead to deep infection and
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Guidelines for the Control of Leprosy in the Northern Territory
3. Callus formation
(due to decrease in sweating) promotes fissuring and ulceration. Callus
formations should be rubbed with pumice stone or an abrasive nylon pad.
4. Joint contractures
should be taught to prevent this result. Involvement of specialist physiotherapy and orthopaedic
care may be required.
can occur when muscles are paralysed and active and passive exercises
5. Eye damage occurs
neuropathy) or lagophthalmos (facial neuropathy). Eyes should be inspected in a mirror daily
for redness. Redness or visual deterioration should be assessed promptly by health staff. Use
of lubricating eye drops or ointment should be encouraged where there is weakness in lid
closure.
because eyes are vulnerable due to corneal sensory loss (trigeminal
Daily regimen for the management of anaesthetic limbs
1. Look
for reddened inflamed skin (hot-spots), blisters or ulceration of anaesthetic areas. Inspect
footwear for foreign bodies with the potential to damage feet, eg pebbles in shoe, nail in sole.
2. Soak
feet and hands if there is sensory loss, dryness, fissuring, callosity, or ulcer in water for
10-15 minutes daily.
3. Pare
scotch-brite pad or pumice stone, until normal tissue is reached. (Health staff can assist this
process periodically using a scalpel blade).
after soaking, abraded areas of built up callus or hardened skin around an ulcer with a
4. Oil
lanolin or vegetable oil are suitable types of emollient.
after soaking and paring to keep the skin supple and retain moisture. Eucerin, vitamin A,
5. Rest
with leg elevated or avoid another long walk until healed. Health staff may assist healing where
ulceration has occurred by providing a sling, crutches, or a Bohler walking iron with plaster of
paris cast or newer alternatives.
Illustrated resources are available that are excellent and provide more detailed prevention of disability
advice for the various impairments. Dr. Grace Warren’s excellent manual,
limbs
in Darwin and Alice Springs. The TB/Leprosy Unit in Darwin can be contacted for details.
where hot-spots or blisters have occurred, avoid pressure to the affected part, eg. restThe care of neuropathic46 is highly recommended and is available in the Department of Health and Families libraries
Guidelines for the Control of Leprosy in the Northern Territory
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Part 3. After MDT completion
Follow-up of leprosy cases
Follow-up after completion of a course of leprosy treatment is essential to ensure:
•
• early detection of disease relapse; and
•
The recommended duration of follow-up by CDC after leprosy cases have completed antimycobacterial
treatment will depend on the type of treatment received.
For an MDT regimen where rifampicin was used for
• early detection of new NFI.
•
• at least a 6-month (PB) period; or
•
• 12 or 24-month (MB) period; and
•
• in daily or monthly administration in combination with dapsone (and clofazimine in MB) there is
good WHO data confirming a low risk of relapse.
Recent cases that received these regimens should be followed according to Part A of Table 18. The
highest incidence of relapse has been reported among MB cases that had a high pre-treatment BI
(≥4+). Cases with bacterial loads less than 4 (BI<4) before treatment have a much lower rate of
relapse after MDT completion and long term routine follow-up is not required.
In addition to relapse, there is also the risk of new NFI, especially in the first 2 years after treatment
commences. Useful predictors of new NFI in the first 2 years after MDT starts are classification (MB
or PB) and/or the presence of NFI at the time of diagnosis of leprosy.
A 2003 study
commenced was:
37,38 reported that the risk of new NFI for 2510 patients followed for 5 years after MDT
•
•
•
•
• PB classification and no NFI at diagnosis – 1.6%• PB classification and NFI at diagnosis – 16%• MB classification and no NFI at diagnosis – 16%• MB classification and NFI at diagnosis – 65%
As 95% of NFI is likely to occur within 2 years PB cases with NFI at diagnosis require VMT-ST
monitoring every 3 months for 2 years and PB cases without NFI at diagnosis require annual
monitoring for 2 years. MB cases will benefit from VMT-ST monitoring monthly throughout the 12
or 24-month period of treatment and should then be followed up for 2 to 5 years after treatment
(Table 18).
For all cases, it is important to remind patients during each examination about the signs that
should prompt presentation to the health services between routine reviews. Scheduled follow-up
examinations by CDC staff are also an ideal time to enquire if other household members have signs
or symptoms of leprosy.
Part B of Table 18 should be used for cases who were treated initially with dapsone and then later
with rifampicin and/or clofazimine, but in whom the total duration of combined treatment was less
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Guidelines for the Control of Leprosy in the Northern Territory
than 6 months (PB) or 12 or 24 months (MB). Patients who received dapsone monotherapy alone
have a high risk of relapse and their follow-up is as per Part C of Table 18.
Table 18. Follow-up of leprosy cases after treatment completion
A. Treatment with WHO-MDT*
Classification
Risk factors NFI at diagnosis BI NFI at
diagnosis
No Yes 0 to 3+ 4+ to 6+ Yes
CDC follow-up
after completion
of treatment
Annually
for 2 years
after MDT
completed
3 monthly
until 2 years
after MDT
completed
Annually
for 2 years
after MDT
completed
3 monthly
for 2 years
then annually
until 5 years
after MDT
completed
3 monthly
for 2 years
then annually
until 5 years
after MDT
completed
Type of follow-up Clinical
Smear
PB (after 6 months of MDT) MB (after 12 or 24 months of MDT)# Clinical# Clinical#∙ Clinical#∙†
Eyes
§
Clinical
#
Smear
†
Eyes
§
B. Treatment with 3 months of daily rifampicin and long term dapsone
Bacterial index
on skin smear at
diagnosis
0 to 3+ 4+ to 6+
CDC follow-up
after completion
of treatment
Discharge after a final
examination
Annually for 15 years
Type of follow-up Clinical
#
Smear (if MB)
†
Clinical
#
Smear
†
Eyes
§
C. Treatment with long term dapsone alone
Bacterial index
on skin smear at
diagnosis
0 to 3+ 4+ to 6+
CDC follow-up
after completion
of treatment
Discharge after a final
examination
Annually for 30 years
Type of follow-up Clinical
#
Smear (if MB)
†
Clinical
#
Smear
†
Eyes
§
* Multiple drug regimen where rifampicin and dapsone in combination (and clofazimine in MB leprosy) was given for at
least a 6 month (PB) or 12 or 24 month (MB) period, regardless of whether rifampicin was given monthly or daily.
# Clinical means skin, nerve, and nerve function impairment (VMT-ST) assessments, including visual acuity.
† Take follow-up smears from 2 sites with the highest BI at the time of diagnosis.
§
Eyes means annual slit-lamp examination by an ophthalmologist to detect silent iritis.
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Relapse of leprosy
Relapse of leprosy in previously treated patients may occur, especially in patients who have not
been treated with a WHO multi-drug regimen. In the MDT era a cure is defined by the completion of
an MDT regimen within a fixed time period (page 28). Thus a relapse is defined as the appearance
of new signs of disease in person who has previously completed a course of treatment and been
declared ‘cured’. By contrast, a new case of leprosy is a person with leprosy who has never
previously been treated.
Treated PB cases presenting with new activity
When previously treated PB cases present with fresh activity in old lesions or the appearance of
new lesions, either relapse or a Type 1 reaction may be the cause. Furthermore a relapse may also
present as a Type 1 reaction. Although the clinical features described in Table 19 are of some use
in differentiating between the 2, there is still considerable overlap.
The most useful criterion is the timing of the new signs. Those which occur within 6 months of
completion of MDT are very likely to be due to Type 1 reaction, whereas those occurring more than
1 year after completion are more likely to be caused by a relapse.
Histological findings are not a useful adjunct. Granulomas in a biopsy do not prove evidence of a
relapse since they are still present in 40% of cases 2 years after the start of MDT. A lymphocytic
infiltrate can also be present in the absence of viable bacilli, being maintained by antigens of dead
bacilli.
It is reported that approximately 50% of patients presenting with new activity post-MDT will have
skin biopsies compatible with active (relapsed) leprosy, and half will have histopathology consistent
with Type 1 reaction.
A course of prednisolone 40mg/day for 4 weeks should be given and if signs and symptoms clear,
a Type 1 reaction is the likely diagnosis. If not, relapse is more likely and the new activity should be
classified as PB or MB in the usual way, and re-treated with MDT.
Treated MB cases presenting with new activity
Relapsed MB patients should be retreated with triple therapy regardless of any change in
classification. There are almost as many combinations of criteria for MB relapse as there are studies
on the relapse of leprosy after MB treatment. It has been acknowledged that MB relapse is easily
over-diagnosed if the following point is not considered:
•
• an increase in BI of 2+ over previously documented BI at that site is required that is confirmed
by 2 sets of skin smears 6 months apart.
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Guidelines for the Control of Leprosy in the Northern Territory
Table 19. Clinically distinguishing relapse from a late Type 1 reaction
Relapse Type 1 reaction
Speed of onset
Slow Sudden
Timing of onset
end of treatment
< 2 (PB) or 5 (MB) years after
end of treatment
> 2 (PB) or 5 (MB) years after
New lesions
+ -
Reappearance of old lesions
+ +
Bacterial index
Increasing Stable or decreasing
Neuritis
nerves
Only in previously affected
In previously unaffected
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