Visceral Leishmaniasis: Treatment

Visceral leishmaniasis is currently treated with pentavalent antimony derivatives (antimony, chemical symbol Sb = Stibium). The derivative most frequently used is Glucantime® (meglumine antimonate, 85 mg Sb/ml) and, rarely, Pentostam® (sodium stibogluconate, 100 mg Sb/ml). The drugs can be administered IM (intramuscularly, painful) or by slow IV (intravenous) injection or infusion (diluted with 5% glucose solution, otherwise local thrombophlebitis occurs). The dose is always expressed as mg Sb: 2 x 10 mg/kg IM or slow IV infusion per day for at least 30 days. As a dose is practically totally excreted and eliminated via the urine within 6 hours after administration, a twice daily administration would pharmacokinetically be more logical than an injection once daily. However, a single administration per day appears to suffice in practice. The dose should be reduced in patients with kidney failure. A maximum of 850 mg/day [10 ml Glucantime®] has been previously set due to the risk of cardiotoxicity with higher doses. This limit has been contested and higher doses are sometimes used. Negativation of T-waves and prolongation of the QT-time are indicative of threatening arrhythmia. The fever usually disappears after 1 week. The spleen begins to get smaller after 2 weeks but frequently requires 6 to 12 months to return to normal.

Follow-up and response in the event of recurrence

Follow-up is necessary as a number of patients will relapse. This usually happens in the first 6 months after treatment. Cases of resistance are not infrequent. Splenectomy sometimes has to be carried out in cases of life-threatening anaemia or thrombocytopaenia. If possible a pneumococcal vaccination should be given before the operation, and lifelong antimalarial prophylaxis is indicated thereafter if the patient stays in an endemic area. Upon recurrence higher doses of Glucantime® can be used for a longer time (2-3 months), though if cost is no problem, amphotericin B can also be used.

Category: Medicine Notes