Comparison of Molecular, Microscopic, and Culture Methods for Diagnosis of Cutaneous Leishmaniasis

Abstract

Cutaneous leishmaniasis (CL) is endemic in the northwest of Isfahan province, Iran. Increase in the incidence of the disease in Kashan has made it necessary to find out the best method for diagnosis and molecular characterization of Leishmania species. In the present study, 130 patients suspected to cutaneous leishmaniosis referred to health care centers of Kashan were examined. Serosity of lesion was collected for smear preparation and cultured in Novy-Nicolle-McNeal medium. DNA was extracted from serosity, and Leishmania species was determined by polymerase chain reaction (PCR) and nested PCR using kinetoplast DNA (kDNA) specific primers. The diagnostic criteria of CL were based on the observation of amastigotes in the smear, promastigotes in culture, presence of expected bands in PCR, or nested PCR. Of 130 specimens, 87 (66.9%), 72 (56.2%), 98 (75.4 %), 96 (73.8%), and 99 (76.2%) were positive for microscopic culture, PCR, nested PCR, and combined PCR and microscopy (proposed method), respectively. Sensitivity, specificity, positive and negative predictive values of PCR were 99%, 100%, 100%, 96.9%, respectively, for microscopy 87.9%, 100%, 100%, 72.1%, for culture 72.7%, 100%, 100%, 53.4 %, and for nested PCR 97%, 100%, 100%, 91.2%, respectively. Based on the results of the study, kDNA-PCR was the most sensitive method for diagnosis of CL.

Real-time PCR using high-resolution melting analysis technology for diagnosis of Leishmania and determination of types of clinical samples

“…Many laboratory methods are used to diagnose leishmaniasis. It has been reported that molecular methods are more sensitive compared to traditional microscopy and culture methods (18)(19)(20). In our study, we detected 28 positive cases by light microscopy and 25 positive cases by real-time PCR.…”

Travelers’ tropical skin diseases: Challenges and interventions

“…Diffuse (anergic) cutaneous leishmaniasis is a more extensive form of cutaneous leishmaniasis characterized by disseminated flesh‐colored papules or nodules. In the New World disease, the most commonly involved Leishmania species are L. mexicana, L. amazonensis, and L. braziliensis (Rasti et al, ).…”

“…As second‐line therapy, liposomal or non‐liposomal amphotericin B is effective in patients who do not respond to antimonials (Vasievich et al, . Also, pentoxifylline can be used as an adjunct to pentavalent antimonials (Rasti et al, ).…”

“…Diffuse (anergic) cutaneous leishmaniasis is a more extensive form of cutaneous leishmaniasis characterized by disseminated flesh-colored papules or nodules. In the New World disease, the most commonly involved Leishmania species are L. mexicana, L. amazonensis, and L. braziliensis(Rasti et al, 2016).Mucocutaneous leishmaniasis is a rare form and can occur 1-2 years after the onset of primary cutaneous disease. It occurs almost exclusively in New World disease.…”

An Overview on Leishmania Diagnosis

“…Rasti et al (2016) compared the sensitivity of microscopic examination, parasite culture and molecular methods for diagnosis of CL, and concluded that despite the convenience and accessibility of the microscopic method, it did not show sufficient sensitivity for the diagnosis of CL [34]. The sensitivity of microscopic methods may increase up to 85% when accompanied by a parasite culture [35].…”