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Some unusual type 2 reactions in leprosy.

V Ramesh¹, Manish Pahwa

¹Department of Dermatology & STD, Safdarjang Hospital & Vardhman Mahavir Medical College, New Delhi, India. weramesh@hotmail.com

International Journal of Dermatology

|May 15, 2010

Summary

Leprosy reactions, including erythema nodosum leprosum (ENL), can occur even with clinically inapparent lepromatous leprosy (LL) outside of multi-drug therapy (MDT). Physicians should maintain high awareness for these reactions, which may be triggered by other illnesses or treatments.

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Area of Science:

Dermatology
Infectious Diseases
Immunology

Background:

Leprosy, specifically lepromatous leprosy (LL), can present with Type 2 reactions, such as erythema nodosum leprosum (ENL), even when not undergoing multi-drug therapy (MDT).
These reactions may occur in patients with clinically inapparent LL, often presenting in general hospital settings.

Purpose of the Study:

To highlight that leprosy reactions can manifest in patients with clinically inapparent lepromatous leprosy (LL) outside of multi-drug therapy (MDT).
To increase physician awareness regarding the diverse presentations of leprosy reactions.

Main Methods:

Case series describing three distinct patient presentations of leprosy reactions.
Diagnostic confirmation involved slit-skin smears (SSS) for acid-fast bacilli (AFB) and histopathology.
Clinical presentations included bullous ENL, ENL resembling immune reconstitution inflammatory syndrome (IRIS), and recurrent Sweet's syndrome-like presentation.

Main Results:

The study describes three prototype cases of leprosy reactions.
Diagnosis was confirmed via demonstration of acid-fast bacilli (AFB) on slit-skin smears (SSS) and histopathology.
One patient had a history of incomplete MDT, and another presented with ENL after treatment for pulmonary tuberculosis.

Conclusions:

Leprosy reactions can occur in patients with clinically inapparent LL, emphasizing the need for physician awareness, especially in general hospitals.
Initial presentations of leprosy as ENL might be precipitated by common antibiotics used for other conditions.
Reactional episodes can occur at any point relative to MDT; ascertaining anti-leprosy therapy status is crucial for appropriate management.