Frequency of Candida Species in Iranian Pediatric Heart Transplant Recipients with and without Diarrhea using PCR-RFLP and Sequencing

Background: Candida species are known as one of the most prevalent agents causing opportunistic gastrointestinal infections in immunodeficient patients. Objective: In this study, species distribution of Candida was determined in pediatric heart transplant recipients with and without gastrointestinal symptoms. Methods: In this study, 59 stool samples were collected from heart transplant recipients including patients with and without gastrointestinal symptoms aged between 1-17 years. The patients underwent heart transplant surgery at Rajaei Cardiovascular, Medical & Research Center, in Tehran. Sabouraud dextrose agar was used for the initial culture, and CHROMagar Candida media were used for initial differentiation. Definitive species identification of Candida isolates was performed using PCR-RFLP and sequencing following DNA extraction. Results: In the present study 13 (22 %) overgrowth isolates associated with patients with gastrointestinal symptoms were positive for Candida spp. using microscopy and culture. The Candida spp. including C. albicans 5 (38.5%), C. glabrata 4 (30.7%), C. guilliermondii 2 (15.4%), and mixed infection of C. albicans and C. glabrata 2 (15.4%) were identified. Conclusion: C. albicans was the predominant species in pediatric heart transplant recipients with Candida intestinal colonization that was substantiated by the presence of pseudohyphae on microscopy, which could be consider as an evidence of invasion.