Cutaneous Leishmaniasis in Khyber Pakhtunkhwa Province of Pakistan: Clinical Diversity and Species-Level Diagnosis

Abstract

This study primarily aimed to identify the causative species of cutaneous leishmaniasis (CL) in the Khyber Pakhtunkhwa Province of Pakistan and to distinguish any species-specific variation in clinical manifestation of CL. Diagnostic performance of different techniques for identifying CL was assessed. Isolates of Leishmania spp. were detected by in vitro culture, polymerase chain reaction (PCR) on DNA extracted from dried filter papers and microscopic examination of direct lesion smears from patients visiting three major primary care hospitals in Peshawar. A total of 125 CL patients were evaluated. Many acquired the disease from Peshawar and the neighboring tribal area of Khyber Agency. Military personnel acquired CL while deployed in north and south Waziristan. Leishmania tropica was identified as the predominant infecting organism in this study (89.2%) followed by Leishmania major (6.8%) and, unexpectedly, Leishmania infantum (4.1%). These were the first reported cases of CL caused by L. infantum in Pakistan. PCR diagnosis targeting kinetoplast DNA was the most sensitive diagnostic method, identifying 86.5% of all samples found positive by any other method. Other methods were as follows: ribosomal DNA PCR (78.4%), internal transcribed spacer 2 region PCR (70.3%), culture (67.1%), and microscopy (60.5%). Clinical examination reported 14 atypical forms of CL. Atypical lesions were not significantly associated with the infecting Leishmania species, nor with “dry” or “wet” appearance of lesions. Findings from this study provide a platform for species typing of CL patients in Pakistan, utilizing a combination of in vitro culture and molecular diagnostics. Moreover, the clinical diversity described herein can benefit clinicians in devising differential diagnosis of the disease.

Clinico-Epidemiological Patterns of Cutaneous Leishmaniasis Patients Attending the Anuradhapura Teaching Hospital, Sri Lanka

“…This is in agreement with previous reports published in Sri Lanka [12]. The clinical appearance of cutaneous lesions varies depending of the immunity of the patient [33] and the species or strain of the causative agent [34]. The study reported a considerably large proportion of leishmaniasis patients among clinically suspected patients.…”

Epidemiology of Cutaneous Leishmaniasis Outbreak, Waziristan, Pakistan

“…P. papatasi is also susceptible to carry L. tropica and is widely distributed in different parts of Pakistan, including Khyber Pakhtunkhwa Province ( 8 ). A previous team had reported L. infantum in 2 army personnel deployed in Waziristan, ( 9 ) but the present detailed study ruled out its presence.…”

Environmental risk modelling and potential sand fly vectors of cutaneous leishmaniasis in Chitral district: a leishmanial focal point of mount Tirich Mir, Pakistan

“…Pakistan is particularly important with respect to leishmaniasis due to occurrence of both ACL and ZCL caused by L. tropica and L. major . The majority of leishmaniasis cases are ACL caused by L. tropica ; confirmed by the currebt study thus deeming L. tropica responsible for the occurrence of disease in the study area . Human population density plays a key role in the spread and distribution of CL, for two major reasons: It is a variable of basic reproduction number for vector‐borne disease, and humans are a host reservoir for the ACL parasite, so ACL can be predicted to be more prevalent in areas with high‐population density (Figure c).…”