Leprosy

LEPROSYLEPROSY

INTRODUCTIONINTRODUCTION Chronic granulomatous infectious disease.Chronic granulomatous infectious disease. Caused by Caused by Mycobacterium lepraeMycobacterium leprae Mainly involves the peripheral nerves and Mainly involves the peripheral nerves and

skin skin Other organs may involve: Other organs may involve:

Mucosa of mouthMucosa of mouthUpper respiratory tractUpper respiratory tractEyesEyesBones & Muscles.Bones & Muscles.Testes etc.Testes etc.

Commonly involves every organ Commonly involves every organ except :except :

CNS, Ovary and Lungs.CNS, Ovary and Lungs.

EpidemioloEpidemiologygy

WORLDWIDE AND INDIAWORLDWIDE AND INDIA

DistributionDistribution PrevalencePrevalence

Worldwide distribution but essentially a Worldwide distribution but essentially a

disease of developing countries. disease of developing countries.

The prevalence rate has dropped by 90 The prevalence rate has dropped by 90

percent from 21.1cases/10000 in 1985 to percent from 21.1cases/10000 in 1985 to

<1/10000 in 2000.<1/10000 in 2000.

To date there has been no resistance to To date there has been no resistance to

antileprosy medicines when used as MDT.antileprosy medicines when used as MDT.

WORLDWIDE WORLDWIDE PREVALENCE AT THE PREVALENCE AT THE TURN OF CENTURYTURN OF CENTURY

Leprosy Situation in India Leprosy Situation in India The goal of leprosy elimination at National level (i.e. PR of <1 The goal of leprosy elimination at National level (i.e. PR of <1 case/10,000 population) as set by National Health Policy 2002 case/10,000 population) as set by National Health Policy 2002

had been achieved in the month of December 2005.had been achieved in the month of December 2005.

associated with poverty and rural residence not associated with AIDS, perhaps because of

leprosy's long incubation period time of peak onset is in the second and third

decades of life India and Africa, 90% of cases are tuberculoid most severe lepromatous form of leprosy is

twice as common among men as among women and is rarely encountered in children

BacterioloBacteriologygy

Lepra bacilliLepra bacilli Gram positive Obligate intracellular bacillus - due Gram positive Obligate intracellular bacillus - due

to its large pool of non functional genes.to its large pool of non functional genes.

Acid fast stained with modified Fite stain or ZN stainAcid fast stained with modified Fite stain or ZN stain

Occurs characteristically in clumps or Occurs characteristically in clumps or

bundles( bundles( ““globiglobi”)”)

Affinity for Schwann cells & cells of R-E system .Affinity for Schwann cells & cells of R-E system .

M. leprae grows best in cooler tissues (the skin,

peripheral nerves, anterior chamber of the eye,

upper respiratory tract, and testes), sparing warmer

areas of the skin (the axilla, groin, scalp, and

midline of the back).

Optimal temp. for growth is 30-33 centigradeOptimal temp. for growth is 30-33 centigrade

M. leprae remains one of the few bacterial species that still has not been cultivated on artificial medium or tissue culture and produces no known toxins, but can grow in Nude mouse Nine banded armadillos(best)

The Leprosy The Leprosy BacteriaBacteria

Reservoir of infectionReservoir of infection

Main reservoir :Main reservoir : Human being Human being Lepromatous case> Non lepromatous Lepromatous case> Non lepromatous

casescases

Animal reservoirsAnimal reservoirs 9-banded armadillos9-banded armadillos ChimpanzeesChimpanzees Mangabey monkeysMangabey monkeys Sphagnum mossSphagnum moss

Portal of exitPortal of exit

Major portal of exitMajor portal of exit : : Nasal MucosaNasal Mucosa LL cases harbour millions of LL cases harbour millions of M. leprae M. leprae

in their nasal mucosa discharged when in their nasal mucosa discharged when they sneeze or blow nose.they sneeze or blow nose.

Ulcerated or broken skin of Ulcerated or broken skin of bacteriologically positive casesbacteriologically positive cases

Mode of transmissionMode of transmission Transmission by inhalationTransmission by inhalation

Droplet infection(most common)Droplet infection(most common)

Transmission by contactTransmission by contact Skin to skin contact with infectious casesSkin to skin contact with infectious cases

Contact with soil or fomitesContact with soil or fomites

Other RoutesOther Routes Insect Vectors e.g.. Mosquito, BedbugsInsect Vectors e.g.. Mosquito, Bedbugs

Tattooing needlesTattooing needles

NB : Breast feeding and Transplacental NB : Breast feeding and Transplacental

infection do not occurinfection do not occur..

Incubation periodIncubation period

Long incubation periodLong incubation period Ranged: 2 to 40 years or moreRanged: 2 to 40 years or more Average: 3-5 yearsAverage: 3-5 years

Generation time Generation time : 12 days(: 12 days(1 day and 20 min for M. tuberculosis and Escherichia coli, respectively)

Infectivity Infectivity : : Leprosy is a highly infectious disease with Leprosy is a highly infectious disease with low pathogenicity. Among household contacts of low pathogenicity. Among household contacts of lepromatous cases about 5 to 12 percent is expected to lepromatous cases about 5 to 12 percent is expected to show signs of leprosy within 5 yrs.show signs of leprosy within 5 yrs.

VIRULENCE FACTORVIRULENCE FACTOR

The bacterium's complex cell wall contains large amounts of an M. leprae–specific phenolic glycolipid (PGL-1), which is detected in serologic tests.

The unique trisaccharide of M. leprae binds to the basal lamina of Schwann cells; this interaction is probably relevant to the fact that M. leprae is the only bacterium to invade peripheral nerves.

Host FactorsHost Factors Leprosy affects all age groups but incidence Leprosy affects all age groups but incidence

generally rises to a peak between 10 to 20 generally rises to a peak between 10 to 20 years of age and then fall.years of age and then fall.

Higher incidence is seen in males, more Higher incidence is seen in males, more marked among adults, more marked among marked among adults, more marked among lepromatous cases.lepromatous cases.

Cell Mediated Immunity is responsible for Cell Mediated Immunity is responsible for resistance to infection with M.resistance to infection with M.leprae.leprae. In In lepromatous leprosy there is complete lepromatous leprosy there is complete breakdown of CMI.breakdown of CMI.

CLASSIFICATION CLASSIFICATION OF OF

LEPROSYLEPROSY

Various ClassificationsVarious Classifications

Indian Classification Indian Classification : : clinicobacteriologicalclinicobacteriological

Madrid Classification Madrid Classification : : clinicobacteriologicalclinicobacteriological

Ridley Jopling classificationRidley Jopling classification : : immunohistologicalimmunohistological

Classification by WHO Study GroupClassification by WHO Study Group on on Chemotherapy of Leprosy : Chemotherapy of Leprosy : clinicobacteriological.clinicobacteriological.

Ridley- Jopling 1966 Ridley- Jopling 1966 (Research purposes)(Research purposes)

Most widely accepted Most widely accepted Divides Leprosy cases into five groups Divides Leprosy cases into five groups

according to their position on an according to their position on an immunohistological scale.immunohistological scale.

It can be used only when full research It can be used only when full research facilities are available :facilities are available :

Tuberculoid (TT)Tuberculoid (TT) Borderline Tuberculoid (BT)Borderline Tuberculoid (BT) Borderline Borderline (BB)Borderline Borderline (BB) Borderline Lepromatous (BL)Borderline Lepromatous (BL) Lepromatous (LL)Lepromatous (LL)

Indian classificationIndian classification

Indeterminate typeIndeterminate type Tuberculoid typeTuberculoid type Borderline typeBorderline type Lepromatous typeLepromatous type Pure neuritic typePure neuritic type

Immunity in leprosyImmunity in leprosy

(-)

(+)

LLHD BLHD BBHD BTHD TTHD

TT -TT -paucibacillary paucibacillary state, few state, few lesions due to lesions due to high immune high immune responseresponse

LL - multibacillary state with multiple lesions due to low immune response

Contd..Contd..

Borderline forms (BB, BT and BL) lie Borderline forms (BB, BT and BL) lie between these two poles and are between these two poles and are immunologically unstable, tending to immunologically unstable, tending to move towards one of the polar formsmove towards one of the polar forms

Immunology & Immunology & bacteriology in leprosy bacteriology in leprosy

(spectrum)(spectrum)

Bacilli

Bacilli

(-)

(+)

(++)

(+++)(+++)

(++)

(+)

(-)

Immunity

Immunity

LLHD BLHD BBHD BTHD TTHD

Clinical Clinical Feature onFeature on

Skin LesionSkin Lesion

Paucibacillary Paucibacillary Leprosy Leprosy

PBPB

Multi Bacillary Multi Bacillary LeprosyLeprosy

MBMBIncluding macular Including macular flat lesion, papules & flat lesion, papules & nodules nodules

1 to 5 lesion1 to 5 lesionAsymmetrical Asymmetrical distributiondistributionDefinite loss of Definite loss of sensationsensation BI <2 at all sites BI <2 at all sites in the initial skin in the initial skin smearsmear

More than 5 lesionMore than 5 lesionSymmetrical Symmetrical distributiondistributionLoss of sensationLoss of sensation

may or may not be may or may not be presentpresent BI >= 2 at any site BI >= 2 at any site in the initial skin in the initial skin smearsmear

WHO WHO Classification(1981,87,93)Classification(1981,87,93)

W H O classificationW H O classification(For chemotherapy – M. (For chemotherapy – M.

leprae)leprae)PaucibacillaryPaucibacillary Indeterminate - IIndeterminate - I Tuberculoid – TTTuberculoid – TT Borderline Borderline

Tuberculoid – BTTuberculoid – BT If any of these have If any of these have

positive bacterial positive bacterial index they should be index they should be classified as classified as multibacillary for multibacillary for multidrug therapymultidrug therapy

MultibacillaryMultibacillary Mid borderline – BBMid borderline – BB Borderline Borderline

Lepromatous – BLLepromatous – BL Lepromatous – LLLepromatous – LL All smear positive All smear positive

casescases

Clinical Clinical FeatureFeature

Indeterminate LeprosyIndeterminate Leprosy Earliest & transitory stageEarliest & transitory stage One or two vague hypopigmented macule One or two vague hypopigmented macule with definite sensory impairment.with definite sensory impairment.

Indeterminate LeprosyIndeterminate Leprosy

If untreated may progress towards If untreated may progress towards

tuberculoid, borderline or lepromatous tuberculoid, borderline or lepromatous

leprosy leprosy Spontaneous regression may occurSpontaneous regression may occur Bacteriologically NegativeBacteriologically Negative

Tuberculoid Leprosy

less severe end of the spectrum encompasses TT and BT disease symptoms confined to the skin and

peripheral nerves most commonly affected are the ulnar,

posterior auricular, peroneal, and posterior tibial nerves

TT leprosy is the most common form of the disease encountered in India

TTTT Single or a few lesionsSingle or a few lesions Asymmetrically distributed on trunk and limbsAsymmetrically distributed on trunk and limbs Sharply defined, dry, flat or raised, Sharply defined, dry, flat or raised,

erythematous or hypopigmented, and are erythematous or hypopigmented, and are

anesthetic.anesthetic. One or two nerves may be enlarged near the One or two nerves may be enlarged near the

skin lesionskin lesion SS for AFB: NegativeSS for AFB: Negative Lepromin test may be strongly positiveLepromin test may be strongly positive

Tuberculoid LeprosyTuberculoid Leprosy

Borderline TuberculoidBorderline Tuberculoid

Four or more lesions, asymmetrically distributedFour or more lesions, asymmetrically distributed

Macules or plaques of variable sizes with well or ill-Macules or plaques of variable sizes with well or ill-

defined margins & satellite lesionsdefined margins & satellite lesions

Peripheral nerves enlarged asymmetricallyPeripheral nerves enlarged asymmetrically

Sensation: hypoesthesiaSensation: hypoesthesia

SS for AFB: may or may not be positive.SS for AFB: may or may not be positive.

Lepromin test may be weakly positiveLepromin test may be weakly positive

Borderline TuberculoidBorderline Tuberculoid

Borderline Leprosy

BB, BLBB, BL Intermediate between BT- and LL-

type lesions; ill-defined plaques with an occasional sharp margin; few or many in number

Hypesthetic or anesthetic skin lesions; nerve trunk palsies, at times symmetric

Borderline BorderlineBorderline Borderline

Multiple erythematous macules & plaquesMultiple erythematous macules & plaques Various sizes and shapes with punched out Various sizes and shapes with punched out

center and ill defined slopping outer margincenter and ill defined slopping outer margin Tend to be symmetricalTend to be symmetrical Nerves may be asymmetrically enlargedNerves may be asymmetrically enlarged Sensation:+/-Sensation:+/- SS for AFB: seen +/-SS for AFB: seen +/- Lepromin test-usually negative, may be Lepromin test-usually negative, may be

doubtfuldoubtful

Borderline BorderlineBorderline Borderline

Borderline Borderline LepromatousLepromatous

Numerous, symmetrically distributed lesionsNumerous, symmetrically distributed lesions

Hypopigmented or erythematous irregularly shaped Hypopigmented or erythematous irregularly shaped

maculopapular, infiltrative nodules, or plaques, with maculopapular, infiltrative nodules, or plaques, with

smooth surfaces & ill defined borders, sloping smooth surfaces & ill defined borders, sloping

outwardsoutwards

Nerves may be symmetrically or asymmetrically Nerves may be symmetrically or asymmetrically

enlarged enlarged

Sensation:+/- Sensation:+/-

SS for AFB: numerous seenSS for AFB: numerous seen

Lepromin test -negativeLepromin test -negative

Borderline LepromatousBorderline Lepromatous

Lepromatous LeprosyLepromatous Leprosy Numerous macules, plaques, nodules or Numerous macules, plaques, nodules or

diffusely infiltrated lesions, shiny, smooth, diffusely infiltrated lesions, shiny, smooth,

symmetrically distributed on face (symmetrically distributed on face (leonine facies), trunk and extremities with ill-, trunk and extremities with ill-

defined margin which may be slightly defined margin which may be slightly

hypopigmented or erythematoushypopigmented or erythematous Symmetrical nerve enlargement is seen Symmetrical nerve enlargement is seen Sensation: normal Sensation: normal SS for AFB: numerous seenSS for AFB: numerous seen Lepromin test - negativeLepromin test - negative

Lepromatous LeprosyLepromatous Leprosy

Ear lobes involvementEar lobes involvement

Diffuse thickening of the skin, with loss of hair (eyebrows and eyelashes) : madarosis.

Saddle nose deformitySaddle nose deformity Leonine faciesLeonine facies

Clinical, Bacteriologic, Pathologic, and Immunologic Spectrum of Leprosy

Feature Tuberculoid (TT, BT) Leprosy

Borderline (BB, BL) Leprosy

Lepromatous (LL) Leprosy

Skin lesion One or a few sharply defined annular asymmetric macules or plaques with a tendency toward central clearing, elevated borders

Intermediate between BT- and LL-type lesions; ill-defined plaques with an occasional sharp margin; few or many in number

Symmetric, poorly marginated, multiple infiltrated nodules and plaques or diffuse infiltration; xanthoma-like or dermatofibroma papules; leonine facies and eyebrow alopecia

Nerve lesion Skin lesions anesthetic early; nerve near lesions sometimes enlarged; nerve abscesses most common in BT

Hypoesthetic or anesthetic skin lesions; nerve trunk palsies, at times symmetric

Hypoesthesia a late sign; nerve palsies variable; acral, distal, symmetric anesthesia common

BI(Bacteriological index) 0-1+ 3-5+ 4-6+

lymphocytes 2+ 1+ 0-1+

Macrophage differentiation

Epitheloid Epitheloid in BB,usually undiff but may have foamy changes in BL

Foamy change is the rule,may be undifferentiated in early lesions

Langhans giant cells 1-3+ - -

Lepromin skin test +++ - -

Lymphocyte transformation test

Generally positive 1 to 10 1 to 2

CD4 : CD8 ratio 1.2 BB(NT),BL:0.48 0.50

PGL1 antibodies 60 85 95

General Findings

Eye : The anterior chamber can be invaded in LL with resultant glaucoma and cataract formation. Iritis/Iridocyclitis

Testes : May be involved in LL with resultant hypogonadism.

Systemic involvement – Respiratory, Bones, Kidneys, Lymph glands, etc.

Nerve Nerve involvement in involvement in

LeprosyLeprosy

M. Leprae M. Leprae : : superficialsuperficial nerve nerve involvementinvolvement

W Britton

Nerve InvolvementNerve Involvement

Neural involvement leads to muscle weakness, muscle atrophy, severe neuritic pain, and contractures of the hands and feet.

Ulnar nerve at elbow is most commonly involved , least common is radial.

Most common cranial nerve involved is Trigeminal.

>30 percent neural loss required for loss of sensation.

First sensation to go is thermal (cold>fine touch). Proprioception is usually preserved.

FaceFaceFacial NerveFacial Nerve LagophthalmosLagophthalmos Facial droopFacial droop

Trigeminal NerveTrigeminal Nerve Corneal anesthesiaCorneal anesthesia

NERVE DAMAGE NERVE DAMAGE UPPER LIMBUPPER LIMB

UlnarUlnar S S Anesthesia medial 1/3 Anesthesia medial 1/3 palmpalm

MM Claw ring and little fingers Claw ring and little fingers

A A Dryness medial 1/3 palm Dryness medial 1/3 palm

MedianMedian SS Anesthesia lateral 2/3 palm Anesthesia lateral 2/3 palm

MM Claw mid + index + loss Claw mid + index + loss OppositionOpposition

AA Dryness lateral 2/3 palm Dryness lateral 2/3 palm

RadialRadial SS Anesthesia dorsum hand Anesthesia dorsum hand

MM Wrist drop Wrist drop

NERVE DAMAGE NERVE DAMAGE

LOWER LIMBLOWER LIMB

Lateral (common) PoplitealLateral (common) Popliteal Foot dropFoot drop

Posterior TibialPosterior TibialSS Sole anesthesia Sole anesthesia

MM Claw Toes Claw Toes

AA Dryness in sole Dryness in sole

DIAGNOSISDIAGNOSIS

HISTORYHISTORY CLINICAL EXAMINATIONCLINICAL EXAMINATION BACTERIOLOGICAL EXAMINATIONSBACTERIOLOGICAL EXAMINATIONS FOOT-PAD CULTUREFOOT-PAD CULTURE HISTAMINE TESTHISTAMINE TEST BIOPSYBIOPSY IMMUNOLOGICAL TESTIMMUNOLOGICAL TEST

DIAGNOSISDIAGNOSISHISTORYHISTORY

History should include the following History should include the following points :points :Patients Bio data : name, age, sex, addressPatients Bio data : name, age, sex, addressPresenting complaintsPresenting complaintsFamily history of leprosyFamily history of leprosyContact with leprosy casesContact with leprosy casesPrevious history of treatment for leprosy, if Previous history of treatment for leprosy, if anyany

DIAGNOSISDIAGNOSISCLINICAL EXAMINATIONCLINICAL EXAMINATION

Physical examination should include :Physical examination should include :A thorough inspection of the body surface(skin).A thorough inspection of the body surface(skin).Palpation of commonly involved superficial Palpation of commonly involved superficial nerves:nerves:1.1.Ulnar N. near the medial epicondyle.Ulnar N. near the medial epicondyle.

2.2.Greater Auricular N as it turns over SCM muscle.Greater Auricular N as it turns over SCM muscle.

3.3.Lateral Popliteal N.Lateral Popliteal N.

4.4.Dorsal branch of Radial N.Dorsal branch of Radial N.Testing for :Testing for :1.1.Loss of sensation : heat, cold, pain, touch .Loss of sensation : heat, cold, pain, touch .

2.2.Paresis or paralysis of muscles of hands and feet.Paresis or paralysis of muscles of hands and feet.

Nerve palpationNerve palpation

DIAGNOSISDIAGNOSISBACTERIOLOGICAL EXAMINATIONBACTERIOLOGICAL EXAMINATION

This includes :This includes :Skin Smears :Skin Smears :Nasal Smears or blows :Nasal Smears or blows :Nasal Scrapings :Nasal Scrapings :

DIAGNOSISDIAGNOSISBACTERIAL INDEXBACTERIAL INDEX

Bacterial index is the only objective way Bacterial index is the only objective way of monitoring benefit of treatment.of monitoring benefit of treatment.

According To According To Ridley’ Logarithmic ScaleRidley’ Logarithmic Scale It Ranges From 0 To 6+ and is based on It Ranges From 0 To 6+ and is based on the no. of bacilli seen in an average the no. of bacilli seen in an average microscopic field.microscopic field.

B 0 stands for no bacilli in any of 100 oil B 0 stands for no bacilli in any of 100 oil immersion field.immersion field.




DIAGNOSISDIAGNOSISMORPHOLOGICAL INDEXMORPHOLOGICAL INDEX

The MI is calculated after examining 200 pink-The MI is calculated after examining 200 pink-stained free standing bacilli.stained free standing bacilli.

The percentage of solid staining bacilli in a The percentage of solid staining bacilli in a stained smear is referred to as MI.stained smear is referred to as MI.

It is a valuable indicator of the patient’s It is a valuable indicator of the patient’s response to treatment during the first few response to treatment during the first few months and helps to signal drug resistance.months and helps to signal drug resistance.

SOLID FRAGMENTED GRANULAR(SFG) SOLID FRAGMENTED GRANULAR(SFG) PERCENTAGEPERCENTAGE : similar to MI but a more : similar to MI but a more sensitive indicator of the patient’s response to sensitive indicator of the patient’s response to treatment.treatment.

DIAGNOSISDIAGNOSISFOOT-PAD CULTUREFOOT-PAD CULTURE

Only certain way of identifying M. Only certain way of identifying M. Leprae.Leprae. 10 times more sensitive at detecting the 10 times more sensitive at detecting the

bacilli than slit skin smear.bacilli than slit skin smear. Time consuming : requires 6 to 9 months.Time consuming : requires 6 to 9 months. Used for :Used for :1.1. Detecting drug resistance.Detecting drug resistance.

2.2. Evaluating the potency of anti-leprosy drugs.Evaluating the potency of anti-leprosy drugs.

3.3. Detecting the viability of bacilli during treatment.Detecting the viability of bacilli during treatment. Newer Newer in vitroin vitro macrophage culture which macrophage culture which

takes only 3 – 4 weeks.takes only 3 – 4 weeks.

DIAGNOSISDIAGNOSISHISTAMINE TESTHISTAMINE TEST

Reliable test for detecting at an early stage peripheral nerve damage due to leprosy.

Method : carried out by injecting 0.1ml of a 1:1000 solution of histamine phosphate into hypopigmented patches or in areas of anesthesia.

Result : in normal person it gives rise to a wheal surrounded by erythematous flare(Lewis triple response). In case of leprosy where the nerve supply is destroyed, flare response is lost.

Particularly useful in cases of indeterminate leprosy.

DIAGNOSISDIAGNOSISBIOPSYBIOPSY

Usually resorted to when there is high Usually resorted to when there is high clinical suspicion but the other test clinical suspicion but the other test are unyielding. It also gives are unyielding. It also gives information about the bacterial information about the bacterial content of skin.content of skin.

DIAGNOSISDIAGNOSISIMMUNOLOGICAL TESTSIMMUNOLOGICAL TESTS

Tests for cell mediated immunity(CMI)Tests for cell mediated immunity(CMI) LEPROMIN TESTLEPROMIN TEST

Tests for humoral antibodies(serological Tests for humoral antibodies(serological tests)tests)

FLA-ABS test FLA-ABS test : : used for detecting subclinical infections. 92.3 percent sensitive and 100 percent specific in detecting specific antibodies in all types leprosy irrespective of type and duration of disease.

Monoclonal antibodiesMonoclonal antibodies Others : RIA, ELISAOthers : RIA, ELISA..

DIAGNOSISDIAGNOSISLEPROMIN TESTLEPROMIN TEST

Method : Method : it is performed by injecting 0.1ml of it is performed by injecting 0.1ml of lepromin into inner aspect of the forearm. The lepromin into inner aspect of the forearm. The reaction is read at 48 hours and 21 days. Two reaction is read at 48 hours and 21 days. Two types of reaction have been described :types of reaction have been described :EARLY REACTION(FERNANDEZ REACTION) : EARLY REACTION(FERNANDEZ REACTION) :

an inflammatory reaction develops within 24 to 48 an inflammatory reaction develops within 24 to 48 hours and this tends to disappear in 3 to 4 days. If the hours and this tends to disappear in 3 to 4 days. If the diameter of the red area is more than 10mm the test is diameter of the red area is more than 10mm the test is considered positive. It is a delayed type hypersensitivity considered positive. It is a delayed type hypersensitivity reaction to soluble constituents of lepra bacilli and reaction to soluble constituents of lepra bacilli and indicates whether or not a person has been sensitized indicates whether or not a person has been sensitized by exposure to and infection by lepra bacilli.by exposure to and infection by lepra bacilli.


LATE REACTION(MITSUDA REACTION) : LATE REACTION(MITSUDA REACTION) : It is characterized by the appearance of a nodule which becomes apparent in 7 to 10 days and reaches its maximum in 3 to 4 weeks. The test is read at 21 days. If the nodule is more than 5 mm it is considered positive. It is induced by the bacillary component and indicates cell mediated immunity.In the first six months of life most children are lepromin negativeBCG vaccination is capable of converting lepra reaction from negative to positive.


VALUE OF LEPROMIN TEST : VALUE OF LEPROMIN TEST : Useful tool for evaluating the immune status of leprosy patients.Aid to classify the type of disease.Estimating the prognosisStrongly positive in a typical tuberculoid case and getting weaker towards the lepromatous end, the typical lepromatous case being lepromin negative indicating failure of CMI.The greatest drawback being high false positive and false negative cases hence not used as a diagnostic test.

OTHER TESTS FOR CMI :OTHER TESTS FOR CMI : Lymphocyte transformation test(LTT) Leucocyte migration inhibition test(LMIT)

TREATMENTTREATMENTMULTIDRUG CHEMOTHERAPYMULTIDRUG CHEMOTHERAPY

In the absence of effective primary In the absence of effective primary prevention by a leprosy vaccine leprosy prevention by a leprosy vaccine leprosy control is based on effective multidrug control is based on effective multidrug chemotherapy(secondary prevention).chemotherapy(secondary prevention).

OBJECTIVES : OBJECTIVES : To interrupt transmission of infectionEarly detection and treatment of cases to prevent deformities To prevent drug resistance


First line drugs First line drugs : rifampicin, dapsone, : rifampicin, dapsone, clofazimine, ethionamide and clofazimine, ethionamide and prothionamide.prothionamide.

Second line drugs Second line drugs : quinolones, : quinolones, minocycline, clarithromycin, minocycline, clarithromycin, aminoglycosidesaminoglycosides


WHO RECOMMENDED REGIMENS OF WHO RECOMMENDED REGIMENS OF CHEMOTHERAPY :CHEMOTHERAPY :

MULTIBACILLARY LEPROSYMULTIBACILLARY LEPROSYRifampicin : 600mg once monthly under supervisionDapsone : 100mg daily self administeredclofazimine : 300mg once monthly under supervision 50mg daily self-administeredWhere clofazimine is unacceptable due skin coloration it may be substituted by 250 to 375mg daily dose of ethionamide or prothionamide. The above regimen needs to taken for 12 months within 18 months


WHO RECOMMENDED REGIMENS OF WHO RECOMMENDED REGIMENS OF CHEMOTHERAPY :CHEMOTHERAPY :

PAUCIBACILLARY LEPROSY PAUCIBACILLARY LEPROSY : :

The above regimen needs to be taken for The above regimen needs to be taken for 6months within 9 months6months within 9 months



Important points :Important points :MDT is not contraindicated in patients with MDT is not contraindicated in patients with HIV infection.HIV infection.MDT is safe during pregnancy.MDT is safe during pregnancy.Drugs are excreted in breast milk but no Drugs are excreted in breast milk but no reports of adverse reaction except for mild reports of adverse reaction except for mild discoloration of infants skin by clofaziminediscoloration of infants skin by clofazimineLeprosy is exacerbated during pregnancy, Leprosy is exacerbated during pregnancy, it is important that MDT is continuedit is important that MDT is continued


DrugsDrugs

Rifampicin : Rifampicin : highly bactericidal, a single 1500mg dose kills 99 percent of viable organismsToxic effects includes anorexia, nausea, vomiting, abdominal discomfort and orange discoloration of body secretions. It is hepatotoxic

Dapsone :Dapsone : weakly bactericidal.Adverse effects include hemolytic anemia, methemoglobinemia, agranulocytosis, hepatitis, neuropathy, psychosis and rarely…


DDS syndrome ch. by fever, maculopapular rash, enlarged lymph nodes, hepatitis and exfoliative dermatitis.

Clofazimine : Clofazimine : was originally synthesized for TB. Less effective than dapsone but has added advantage of preventing lepra reaction. More expensive but less toxic which includes dark red discoloration of skin, mucus membranes, sweat and urine.


Ethionamide and Prothionamide :Ethionamide and Prothionamide : highly bactericidal killing 98 percent of viable bacilli in 3 to 4 days. Relatively more expensive and more toxic.

LEPRA REACTIONSLEPRA REACTIONS

During the course of leprosy, During the course of leprosy, immunological mediated episodes of acute immunological mediated episodes of acute or subacute inflammation known as or subacute inflammation known as reaction may occur.reaction may occur.

There are two types of reactions :There are two types of reactions : Type 1 or Reversal reactionType 1 or Reversal reaction Type 2 or erythema nodosum leprosumType 2 or erythema nodosum leprosum

Both types can occur before the start of Both types can occur before the start of MDT, during treatment or after MDT, during treatment or after completion of treatment.completion of treatment.

REVERSAL/REVERSAL/DOWNGRADING DOWNGRADING

REACTIONREACTION occur in almost half of patients with

borderline forms of leprosy but not in patients with pure lepromatous disease

Manifestations include classic signs of inflammation within previously involved macules, papules, and plaques and, on occasion, the appearance of new skin lesions

nerve trunk most commonly involved in this process is the ulnar nerve at the elbow, which may be painful and exquisitely tender

most dramatic manifestation is footdrop, which occurs when the peroneal nerve is involved.

(less commonly) fever—generally low-grade

type 1 lepra reactions precede the initiation of appropriate antimicrobial therapy, they are termed downgrading reactions, and the case becomes histologically more lepromatous

when they occur after the initiation of therapy, they are termed reversal reactions, and the case becomes more tuberculoid

often occur in the first months or years after the initiation of therapy

LEPRA REACTIONSLEPRA REACTIONSERYTHEMA NODOSUM LEPROSUMERYTHEMA NODOSUM LEPROSUM

In ENL new inflamed, red nodules appear under In ENL new inflamed, red nodules appear under the skin, while the original lesions remain same. the skin, while the original lesions remain same. Commonly on face, arm and legs & bilaterally Commonly on face, arm and legs & bilaterally symmetrical. They appear in crops and subside symmetrical. They appear in crops and subside within few days even without treatmentwithin few days even without treatment

It is antigen antibody reaction.It is antigen antibody reaction. Seen in MB cases only.Seen in MB cases only. Nerves may be affected but is uncommonNerves may be affected but is uncommon Other organs like testis, eye, kidney may be Other organs like testis, eye, kidney may be

affectedaffected General symptoms of fever, joint pain, red eyes and General symptoms of fever, joint pain, red eyes and

watering may be associated.watering may be associated.

ERYTHEMA NODOSUM ERYTHEMA NODOSUM LEPROSUMLEPROSUM

occurs exclusively in patients near the lepromatous end of the leprosy spectrum (BL-LL)

90% of cases it follows the institution of chemotherapy, generally within 2 years

most common features of ENL are crops of painful erythematous papules that resolve spontaneously in a few days to a week but may recur; malaise; and fever

may also experience symptoms of neuritis, lymphadenitis, uveitis, orchitis, and glomerulonephritis and may develop anemia, leukocytosis, and abnormal liver function tests

Elevated levels of circulating tumor necrosis factor (TNF) have been demonstrated in ENL; thus, TNF may play a central role in the pathobiology of this syndrome

thought to be a consequence of immune complex deposition

LEPRA REACTIONSLEPRA REACTIONSTREATMENTTREATMENT

Because of high risk of permanent nerve Because of high risk of permanent nerve damage reversal reaction needs to be damage reversal reaction needs to be promptly diagnosed and treated adequatelypromptly diagnosed and treated adequately

Standard 12 wk. regimen of prednisolone is Standard 12 wk. regimen of prednisolone is the treatment of choice.the treatment of choice.

ENL varies in severity, duration and organ ENL varies in severity, duration and organ involvement, and can be treated with involvement, and can be treated with prednisolone as reversal reaction.prednisolone as reversal reaction.

Treatment includes bed rest, splinting of Treatment includes bed rest, splinting of affected nerves, analgesics and prednisolone.affected nerves, analgesics and prednisolone.


Prednisolone regimen Add clofazimine in ENL

40mg daily for first 2 weeks30mg daily or week 3 and 4

100mg tds x 4 weeks

20mg daily for week 5 and 615mg daily for week 7 and 8

100mg bd x 4weeks

10mg daily for week 9 and 105mg daily for week 11 and 12

100mg od x 4 weeks

For neuritis, treatment with prednisolone 20mg onwards

Should be prolonged to four weeks from


For pregnant women prednisolone should be started For pregnant women prednisolone should be started at 30mg dose instead of 40mg and limit the course at 30mg dose instead of 40mg and limit the course for 10weeks in PB cases and 20 weeks for MB cases.for 10weeks in PB cases and 20 weeks for MB cases.

For children dose should be started at 1mg/kg of For children dose should be started at 1mg/kg of body wt. per day.body wt. per day.

Thalidomide : Thalidomide : was reintroduced for the treatment of ENL, mainly because of its antipyretic action. WHO does not recommend the use of thalidomide in leprosy. Prednisolone is more effective in controlling ENL and associated neuritis, clofazimine is the drug of choice for the management of chronic, recurrent ENL reactions. Another drug claimed to be useful in ENL is pentoxyfylline.

Thank YouThank You

Date post:	07-May-2015
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