BACKGROUND: Traditional detection of Leishmania from ulcers involves collection of invasive specimens that cause discomfort, require technical expertise, and carry risks of invasive procedures. We compared traditional diagnostic methods with a molecular noninvasive filter paper-based method for the diagnosis of cutaneous leishmaniasis. METHODS: Consecutive patients presenting to the Leishmania Clinic at Hospital Nacional Cayetano Heredia were enrolled. Polymerase chain reaction (PCR) was performed on lesion scrapings, aspirates, and filter paper impressions. The reference standard was any 2 of 5 tests positive: smear, aspirate culture, invasive-specimen PCR (scrapings and aspirates), filter paper PCR, and leishmanin skin test. Outcome measures were sensitivity and specificity. Leishmania speciation was performed by PCR-restriction fragment length polymorphism (RFLP) of positive specimens. RESULTS: Forty-five patients with 66 lesions were enrolled. Of 52 lesions diagnosed as cutaneous leishmaniasis, 50 were positive by PCR of invasive specimens versus 48 by PCR of filter papers (P=.930). Sensitivity and specificity of PCR on invasively obtained specimens were 94.2% (95% confidence interval [CI], 87.9%-100%) and 92.9% (95% CI, 79.4%-100%). Sensitivity and specificity of filter paper PCR were 92.3% (95% CI, 85.1%-99.5%) and 100%. Culture, smear, and leishmanin skin test all had inferior sensitivities, compared with PCR of invasive or noninvasive specimens (P<.001). Of 50 specimens positive by PCR, 19 had sufficient DNA for PCR-RFLP analysis. CONCLUSIONS: Filter paper PCR constitutes a sensitive and specific alternative to traditional diagnostic assays. This novel, rapid, well-tolerated method has the potential for widespread use in the field and in pediatric populations where traditional specimen collection is most difficult to perform, and can potentially be used for rapid species identification.
BACKGROUND: Traditional detection of Leishmania from ulcers involves collection of invasive specimens that cause discomfort, require technical expertise, and carry risks of invasive procedures. We compared traditional diagnostic methods with a molecular noninvasive filter paper-based method for the diagnosis of cutaneous leishmaniasis. METHODS: Consecutive patients presenting to the Leishmania Clinic at Hospital Nacional Cayetano Heredia were enrolled. Polymerase chain reaction (PCR) was performed on lesion scrapings, aspirates, and filter paper impressions. The reference standard was any 2 of 5 tests positive: smear, aspirate culture, invasive-specimen PCR (scrapings and aspirates), filter paper PCR, and leishmanin skin test. Outcome measures were sensitivity and specificity. Leishmania speciation was performed by PCR-restriction fragment length polymorphism (RFLP) of positive specimens. RESULTS: Forty-five patients with 66 lesions were enrolled. Of 52 lesions diagnosed as cutaneous leishmaniasis, 50 were positive by PCR of invasive specimens versus 48 by PCR of filter papers (P=.930). Sensitivity and specificity of PCR on invasively obtained specimens were 94.2% (95% confidence interval [CI], 87.9%-100%) and 92.9% (95% CI, 79.4%-100%). Sensitivity and specificity of filter paper PCR were 92.3% (95% CI, 85.1%-99.5%) and 100%. Culture, smear, and leishmanin skin test all had inferior sensitivities, compared with PCR of invasive or noninvasive specimens (P<.001). Of 50 specimens positive by PCR, 19 had sufficient DNA for PCR-RFLP analysis. CONCLUSIONS: Filter paper PCR constitutes a sensitive and specific alternative to traditional diagnostic assays. This novel, rapid, well-tolerated method has the potential for widespread use in the field and in pediatric populations where traditional specimen collection is most difficult to perform, and can potentially be used for rapid species identification.
Authors: Andrea K Boggild; Ana Pilar Ramos; Braulio Mark Valencia; Nicolas Veland; Flor Calderon; Jorge Arevalo; Donald E Low; Alejandro Llanos-Cuentas Journal: J Clin Microbiol Date: 2010-12-22 Impact factor: 5.948
Authors: Hirotomo Kato; Abraham G Cáceres; Tatsuyuki Mimori; Yuka Ishimaru; Amal S M Sayed; Megumi Fujita; Hiroyuki Iwata; Hiroshi Uezato; Lenin N Velez; Eduardo A L Gomez; Yoshihisa Hashiguchi Journal: J Clin Microbiol Date: 2010-08-18 Impact factor: 5.948
Authors: Nicolas Veland; Braulio Mark Valencia; Milena Alba; Vanessa Adaui; Alejandro Llanos-Cuentas; Jorge Arevalo; Andrea K Boggild Journal: Am J Trop Med Hyg Date: 2013-02-04 Impact factor: 2.345
Authors: Nicolas Veland; Andrea K Boggild; Cristian Valencia; Braulio M Valencia; Alejandro Llanos-Cuentas; Gert Van der Auwera; Jean-Claude Dujardin; Jorge Arevalo Journal: J Clin Microbiol Date: 2011-11-23 Impact factor: 5.948
Authors: Nicolas Veland; Diego Espinosa; Braulio Mark Valencia; Ana Pilar Ramos; Flor Calderon; Jorge Arevalo; Donald E Low; Alejandro Llanos-Cuentas; Andrea K Boggild Journal: Am J Trop Med Hyg Date: 2011-04 Impact factor: 2.345