Treatment of Leishmaniasis
Visceral Leishmaniasis (VL)
For visceral leishmaniasis in immunocompetent patients, combination therapy with liposomal amphotericin B (L-AmB) plus miltefosine or paromomycin is now the preferred first-line treatment in the Indian subcontinent, achieving cure rates of 93-98.7% with fewer adverse events than monotherapy. 1
Geographic-Specific Regimens:
Indian Subcontinent (L. donovani):
- First-line (Grade AI): Either:
- L-AmB 5 mg/kg IV single dose + miltefosine orally for 7-14 days, OR
- Paromomycin 15 mg/kg/day IM for 10 days + miltefosine for 10 days 1
- Alternative monotherapy (Grade BI): Miltefosine alone for 28 days (dosing: 2.5 mg/kg/day in children 2-11 years; 50 mg/day if ≥12 years and <25 kg; 100 mg/day if ≥12 years and 25-50 kg; 150 mg/day if >50 kg) 1
- Caveat: Recent reports show declining cure rates with miltefosine monotherapy, potentially due to emerging resistance 1
East Africa (L. donovani):
- 17-day combination of pentavalent antimonials (SbV) + paromomycin remains standard 2
- Miltefosine monotherapy shows moderate efficacy (75.6% cure rate) 1
Mediterranean/South America (L. infantum):
Critical Pitfall:
Children <12 years have higher treatment failure rates with miltefosine, likely requiring dose adjustments beyond current recommendations 1. Premature discontinuation due to gastrointestinal side effects combined with miltefosine's long half-life creates subtherapeutic levels that promote resistance 1.
Visceral Leishmaniasis with HIV Co-infection
Liposomal amphotericin B is the drug of choice for HIV-coinfected patients with VL, using higher doses and longer durations than in immunocompetent patients. 3
Treatment Protocol:
- FDA-approved regimen: L-AmB 4 mg/kg/day IV on days 1-5,10,17,24,31, and 38 (total 40 mg/kg) 3
- Higher total doses (30-50 mg/kg) may be needed depending on immunosuppression level 4, 5
- Reduce immunosuppressive medications during treatment when possible 3
Secondary Prophylaxis:
- Indicated for: Severely immunosuppressed patients (CD4 <200 cells/mm³) after initial treatment 3
- Regimens:
- L-AmB 3-5 mg/kg IV every 3-4 weeks, OR
- Pentamidine 4 mg/kg (max 300 mg) every 2-4 weeks 3
- Discontinuation: Consider when CD4 >200-350 cells/mm³ for ≥6 months on ART, though relapses can occur even with higher CD4 counts 3
Critical Warning:
Miltefosine monotherapy in HIV-coinfected patients shows poor outcomes with high relapse rates (nearly all patients relapsed in European studies) 1. In Ethiopia, miltefosine was safer but less effective than sodium stibogluconate for VL/HIV coinfection 1.
Cutaneous Leishmaniasis (CL)
Old World CL:
For L. major infections in Iran, miltefosine for 28 days is as effective as intralesional antimonials (Grade BI), with cure rates of 87-100%. 1
- Dosing: Same weight-based dosing as VL for 28 days 1
- Other species (L. tropica, L. infantum): Evidence limited to case reports (Grade CIII) 1
- Alternative: Combination of cryotherapy plus intralesional antimony for uncomplicated cases 4
New World CL:
Treatment efficacy varies significantly by species and geography:
L. panamensis (Colombia):
- Miltefosine for 20-28 days: >80% cure rate (Grade BI) 1
L. braziliensis:
- Bolivia/Brazil: 75-80% cure rate with miltefosine 1
- First-line: 20-day course of meglumine antimoniate 4
- Guatemala: Only 50% cure rate with miltefosine 1
L. guyanensis (Brazil):
CL in HIV-Coinfected Patients:
Systemic therapy is prudent even for seemingly focal lesions due to dissemination risk, regardless of causative species. 3
- Any Leishmania species can cause cutaneous, mucosal, or visceral dissemination in HIV patients 3
- Higher rates of treatment failure and relapse compared to immunocompetent patients 3
- Consider L-AmB-based regimens given better safety profile 3
Mucosal/Mucocutaneous Leishmaniasis (ML)
For New World mucocutaneous leishmaniasis caused by L. braziliensis, miltefosine 2.5-3.3 mg/kg/day for 28-42 days achieves 83% cure rates for moderate disease (Grade BII). 1
Treatment Considerations:
- Moderate disease: 28 days treatment (83% cure rate) 1
- Severe disease: Extend to 42 days (58% cure rate at 28 days, improved with longer duration) 1
- Longer treatment duration (4-6 weeks) improves outcomes 1
ML in HIV-Coinfected Patients:
- ML can be the first manifestation in coinfected patients, sometimes followed by cutaneous lesions 3
- Clinical spectrum broader and more complex than in immunocompetent patients 3
- No established treatment regimen; systemic therapy essential 3
Post-Kala-Azar Dermal Leishmaniasis (PKDL)
For PKDL in India, miltefosine 100-150 mg/day for 60-90 days achieves cure rates of 76-96% (Grade BI). 1
Dosing Protocol:
- Start with 150 mg/day for 60 days 1
- Extend to 90 days if inadequate response 1
- Alternative: Miltefosine 2.5 mg/kg/day for 8-12 weeks (76-78% cure rates) 1
Special Populations
Pregnancy:
Miltefosine is contraindicated in pregnancy due to fetotoxicity. 1
- L-AmB is the safest option during pregnancy
- Effective contraception required during and for 5 months after miltefosine treatment
Immunosuppressed (Non-HIV):
- L-AmB remains first-line 3
- Higher doses than immunocompetent patients (cumulative 30-40 mg/kg vs 20 mg/kg) 4
- Secondary prophylaxis until immune reconstitution for ≥6 months 4
- Higher treatment failure and relapse rates than HIV-uninfected immunosuppressed patients 3
Key Implementation Considerations
Resistance Concerns:
The Indian subcontinent faces emerging miltefosine resistance due to:
- Premature treatment discontinuation from rapid clinical improvement 1
- Gastrointestinal side effects leading to poor compliance 1
- Long elimination half-life creating prolonged subtherapeutic levels 1
- Anthroponotic transmission amplifying resistant parasites 1
Drug Interactions:
- Antiretroviral agents may interact with pentavalent antimonials and miltefosine 3
- Azole antifungals (ketoconazole, itraconazole, fluconazole) interact with antiretrovirals 3