Isolation of bacteria causing secondary bacterial infection in the lesions of cutaneous leishmaniasis

Abstract

Background:Cutaneous Leishmaniasis (CL) is a parasitic disease characterized by single or multiple ulcerations. Secondary bacterial infection is one of the complications of the disease that can increase the tissue destruction and the resulting scar.Objective:To effectively determine the incidence of real secondary bacteria infection in cutaneous leishmaniasis, we designed the current study.Methods and Materials:This was a cross-sectional study performed in Skin Diseases and Leishmaniasis Research Centre, Isfahan, Iran. In this study, 854 patients with confirmed CL were enrolled. Samples were taken from all the patients. Sterile swaps were achieved for the ulcer exudates and scraping was used for nonulcerated lesions. All the samples were transferred to tryptic soy broth medium. After 24 h of incubation in 37°C, they were transferred to eosin methylene blue agar (EBM) and blood agar. Laboratory tests were used to determine the species of bacteria. All of the collected data were analyzed by SPSS software and chi-square.Results:Among 854 patients with confirmed cutaneous leishmaniasis, 177 patients (20.7%) had positive cultures for secondary bacterial infection. Bacteria isolated from the lesions were as follows: Staphylococcus aureus - 123 cases (69.4%), coagulase negative Staphylococcus - 41 cases (23.1%), E. coil - 7 cases (3.9%), Proteus - 3 cases (1.7%) and Klebsiella - 3 cases (1.7%).Conclusions:The incidence of secondary bacterial infection in lesions of CL was 20.7%. The most common isolated pathogen was Staphylococcus aureus. The incidence of secondary bacterial infection was significantly more in the ulcerated lesions as compared with nonulcerated lesions (P = 0.00001).