Treatment of Leprosy and Leprosy Reactions

Abstract

Leprosy is classified as a tropical neglected disease by the World Health Organization (WHO). In the 1980s, the prevalence of leprosy around the world was approximately 12 million cases, while in the early 2000s, it declined to around 800,000 cases. Most cases occur in India, Brazil, and Indonesia, and are caused by Mycobacterium leprae. A special clinical presentation, called diffuse lepromatous leprosy, is caused by Mycobacterium lepromatosis, and most cases have been reported in Mexico. The incidence and prevalence worldwide have steadily declined in recent decades. This dramatic change is accountable to multidrug therapy. Diagnosis is supported by clinical presentation, baciloscopy, intradermal reaction, and skin biopsy. Leprosy can cause reactions, most frequently type 2 reaction (erythema nodosum leprosum). The key drugs used to treat leprosy are dapsone, rifampicin, and clofazimine. The WHO has classified two clinical scenarios (multibacillary and paucibacillary cases), which are very useful for treatment choosing, especially treatment duration. Dosage for multibacillary cases includes dapsone 100 mg/daily, clofazimine 50 mg/daily and a 300 mg/monthly dose, and rifampicin 600 mg/monthly for 12 months at least. For best response and minimum relapse, the drug regimen should be maintained for 24 months. Paucibacillary cases are treated with dapsone 100 mg/day and rifampicin 600 mg/monthly for 6 months. Type 1 reactions (neuritis) are managed with corticosteroids 25–50 mg/day until resolution. Type 2 reactions (erythema nodosum leprosum) should be treated with thalidomide 100–200 mg/daily, clofazimine 200 mg/daily, and pentoxifylline 800 mg/daily. Second-line antileprosy drugs include clarithromycin, ofloxacin, moxifloxacin, and minocycline. Relapse and resistance may occur. Antimicrobial resistance assays must be performed in case of treatment failure or relapse.