Kala-azar--new developments in diagnosis and treatment.

Kala-azar is an endemic disease in many parts of India. Traditionally, diagnosis of this disease was based on demonstrating the parasites in various tissues like bone marrow or splenic aspirates. However, lack of high sensitivity of these methods led to the use of various immunodiagnostic methods in the diagnosis of kala-azar. Antigen detection and polymerase chain reaction to detect parasitic DNA have been found to be useful in patients with an underlying immunosuppressive disease like AIDS. For treating kala-azar, pentavalent antimonial compounds are still the first-line agents. However, due to increasing resistance to this agent, many patients at present require other drugs including amphotericin B and pentamidine. Toxic effects of these second-line agents have led to development of drug delivery systems like liposomal amphotericin B, which has shown uniform efficacy in clinical trials. Combining stibogluconate with either paromomycin or interferon-gamma has also been shown to be useful in many patients with drug-resistant kala-azar.