Lepromin test is seen on:
Ans. d (4th week). (Ref. Ananthanarayan, Microbiology, 4th ed. 365)Patch test:2nd dyEarly Fernandez reaction:2nd dyInduration in TB seen after:3 dys of tuberculin injectionIn Psoriasis the skin doubling time:4 dysKviem test:2nd week (positive)Late Mistsuda reaction:3rd weekNormal skin doubling time:4 weeksLEPROMIN TEST# Mitsuda first described lepromin test.# Intradermal injection of lepromin antigen is typically biphasic in reaction, early Fernandez reaction characterized by erythema and induration in 24-48 hours and lasting for 3-5 days, analogous to tuberculin test, but of no significance, late is Mitsuda reaction in 4 weeks (peak) and subsides with ulceration, it is the measure of CMI.# Principle of test: Delayed hypersensitivity reaction.# Lepromin used:- Uman type- Armadillo type- Dharmendra antigen# Purpose of test:- For classification of leprosy- For assessment of prognosis and response to treatment (not used for diagnosis)- To assess resistance of the individual- To verify the identity of candidate lepra bacillusEducational points:LEPRA REACTIONCharacteristicsType 1Type IIImmunologic basisCell mediatedAg Ab reactionType of hypersensitivityType IVType IIISystemic disturbances-+Changes in blood picture-+Albuminuria-+Type of patientBT, BB, BLBL and LLTreatmentSteroidsThalidomide Clofazimine Continue DapsoneSteroid (Drug of choice)Lucio phenomenon: Rare reaction in LL due to vasculitis, seen in untreated patients, characterized by tender and red patches and vesicles especially over legs.
3rd day
7th day
2nd week
4th week
Mycobacteria