Background: The old short course regimens of pentavalent antimonial (sb(v)) therapy of visceral leishmaniasis (VL) have largely been abandoned worldwide as they are associated with increasing problems of relapse and unresponsiveness. In Ethiopia, some hospitals still use the old interrupted and short course regimen partly because of fear of drug toxicity.
Objective: To evaluate the safety of the WHO recommended uninterrupted therapy at a dose of 20 mg sb(v)/kg for up to thirty days.
Design: A prospective study.
Setting: Patients were recruited from Addis Ababa hospitals and from Konso VL endemic area in southern Ethiopia.
Subjects: Forty nine patients who included, ten HIV-positive and 39 HIV-negative, were enrolled for the study.
Results: Twenty three HIV-negative patients got treatment for 20 days and the rest, 16 HIV-negative and 10 HIV-positive, were treated for 28 to 30 days. Among HIV-seronegatives, the mean QT interval corrected for heart rate (QTc) at the end of therapy in patients treated for 20 days and 28-30 days was comparable (0.419 +/- 0.031 seconds versus 0.424 +/- 0.027 seconds, respectively). Among patients treated for 28-30 days, the mean QTc in HIV co-infected patients was comparable to that of HIV-negatives (0.416 +/- 0.018 seconds versus 0.424 +/- 0.027). Comparable rates of new ECG changes involving the T waves were observed in two HIV-positive (20%) and two HIV-negative (12.5%) patients treated for 28-30 days, and in seven (30.4%) HIV-negative patients treated for 20 days. Overall, only two (4.1%) patients (all HIV-negative males) had QTc interval > or = 0.50 seconds at the end of therapy. In one patient, the prolonged QTc was noted on the twentieth day with bradycardia of 44/minute.
Conclusions: In Ethiopian VL patients with normal renal function, sb(v) therapy at a daily dose of 20 mg/kg for up to 30 days is safe and only rarely associated with clinically significant bradycardia which resolves after temporary cessation of therapy. Furthermore, in areas with limited facilities, monitoring the pulse rate during antimonial therapy may help detect impending cardiotoxicity.