Clinical and parasite species risk factors for pentavalent antimonial treatment failure in cutaneous leishmaniasis in Peru.
BACKGROUND
Treatment for cutaneous leishmaniasis (CL) with standard pentavalent antimonial therapy is hampered by cumbersome administration, toxicity, and potential failure. Knowledge of factors influencing treatment outcome is essential for successful management.


METHODS
A case-control study of incident cases was performed with patients experiencing their first CL episode. The standard treatment for CL for these patients was 20 mg/kg/day of sodium stibogluconate for 20 days. Clinical and epidemiological data were recorded, and parasite isolates were species typed. Patients were followed up for 6 months to assess treatment outcome. Clinical cure was defined as complete wound closure and re-epithelization without inflammation or infiltration; new lesions, wound reopening, or signs of activity were classified as treatment failure. Descriptive, bivariate, and logistic regression analyses were performed.


RESULTS
One hundred twenty-seven patients were recruited; 63 (49.6%) were infected with Leishmania (Viannia) peruviana, 29 (22.8%) were infected with Leishmania (Viannia) braziliensis, 27 (21.3%) were infected with Leishmania (Viannia) guyanensis, and 8 (6.3%) were infected with other species. Only patients infected with the 3 most common species were selected for risk-factor analysis (n=119). Final failure rate at 6 months was 24.4% (95% confidence interval [CI], 16.5%-32.1%), with 96% of failures occurring within the first 3 months of follow-up assessment. Risk factors for treatment failure identified in the final multivariate model were age (per year, odds ratio [OR], 0.95; 95% CI, 0.92-0.99; P=.017), stay of <72 months in area of disease acquisition (OR, 30.45; 95% CI, 2.38-389.25; P=.009), duration of disease <5 weeks (OR, 4.39; 95% CI, 1.12-17.23; P=.034), additional lesion (per lesion, OR, 2.06; 95% CI, 1.3-3.28; P=.002), infection with L. (V.) peruviana (OR, 9.85; 95% CI, 1.01-95.65; P=.049), and infection with L. (V.) braziliensis (OR, 22.36; 95% CI, 1.89-263.96; P=.014).


CONCLUSIONS
The identification of parasite species and clinical risk factors for antimonial treatment failure should lead to an improved management of CL in patients in Peru.
Llanos-Cuentas
Alejandro
A
Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
Tulliano
Gianfranco
G
Araujo-Castillo
Roger
R
Miranda-Verastegui
Cesar
C
Santamaria-Castrellon
Giovanna
G
Ramirez
Luis
L
Lazo
Marcela
M
De Doncker
Simonne
S
Boelaert
Marleen
M
Robays
Jo
J
Dujardin
Jean-Claude
JC
Arevalo
Jorge
J
Chappuis
Francois
F
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000818:Animals; D000967:Antimony Sodium Gluconate / Q000008:administration & dosage* / Q000009:adverse effects; D000981:Antiprotozoal Agents / Q000008:administration & dosage* / Q000009:adverse effects; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D007891:Leishmania / Q000302:isolation & purification*; D016773:Leishmaniasis, Cutaneous / Q000188:drug therapy* / Q000469:parasitology*; D008297:Male; D010568:Peru; D011446:Prospective Studies; D012307:Risk Factors; D017211:Treatment Failure
D000981:Antiprotozoal Agents; D000967:Antimony Sodium Gluconate