A comparative study of the diagnosis of Old World cutaneous leishmaniasis in Iraq by polymerase chain reaction and microbiologic and histopathologic methods

Abstract

Background: The diagnosis of cutaneous leishmaniasis (CL) largely depends on the clinical appearance, especially in endemic areas. A diagnostic challenge arises when the lesions appear in nonendemic areas, when the clinical picture is distorted, or when an atypical variant is seen, even in endemic regions. Aim To assess the correlation of microbiologic and histopathologic diagnosis with polymerase chain reaction (PCR) findings in clinically diagnosed cases of CL.

Methods: This was an observational and descriptive study. The patients were seen at outpatient departments of dermatology in the middle Euphrates region of Iraq. Sixty-five patients with clinically suspicious CL lesions were screened. Fifty-seven clinically diagnosed cases were then subjected to slit-skin smear and skin biopsy. PCR examination was conducted in 40 cases.

Results: Direct slit-skin smear examination was positive in 38 patients (66.7%), and 48 specimens (84.2%) were positive by the slide-touch skin biopsy method. Histopathologic examination showed features suggestive of CL in 34 specimens (59.6%). The results of PCR examination were positive in 37 cases (92.5%).

Conclusion: The PCR technique is highly specific (100%) and sensitive (92.5%) for the diagnosis of CL. In addition to the confirmation of the diagnosis, it may be useful in identifying a relationship between the type of microorganism and the clinical presentation of the disease.