Clinical course of erythema nodosum leprosum: an 11-year cohort study in

Abstract. Erythema nodosum leprosum (ENL) or type 2 lepra reactions complicate lepromatous leprosy and bor-derline lepromatous leprosy. We report an 11-year retrospective case record analysis of 481 outpatients with borderline lepromatous and lepromatous leprosy at the Dhoolpet Leprosy Research Center in Hyderabad, India.. The overall prevalence of ENL was 24%, 49.4 % among cases of lepromatous leprosy (LL) and 9 % among cases of borderline lepromatous (BL) leprosy. Logistic regression analysis identified LL (odds ratio [OR] 8.4, 95 % confidence interval [CI] 4.6–15.4, P < 0.001) and BL with a bacterial index 4+ (OR 5.2, 95 % CI 2.1–12.9, P 0.001) as major risk factors. The average patient with ENL was male, 34.7 years of age, and had multiple episodes of ENL (mean 3.1) over an 18.5-month period. Three types of ENL were identified: single acute ENL, multiple acute ENL (repeated discrete episodes), and chronic ENL (continuous episodes). Acute single ENL is rare, accounting for only 8 % of cases. Chronic ENL accounted for 62.5 % of the cohort. Chronic ENL was of longer duration and more severe. An age 35 years was a risk factor for developing chronic ENL. Patients with chronic ENL were more compliant with multi-drug therapy, especially during the first six doses of multi-drug therapy. Distinguishing these different types of ENL would be useful for patient management and developing improved treatment of these debilitating reactions. Improved strat-egies for treatment and management of these reactions need to be developed