Unraveling the Cryptosporidium Threat: Epidemiology, Genetic Diversity, and Prevalence in HIV-Positive Patients in Tehran, Iran

Abstract

The primary objective of this study was to evaluate the prevalence and genetic diversity of Cryptosporidium infection in 100 HIV-positive patients. In addition, we aimed to investigate the risk factors and clinical outcomes associated with Cryptosporidium infection in patients with HIV in Iran. Moreover, the present study focused on assessing the relationship between Cryptosporidium infection and multiple factors, namely sociodemographic characteristics, clinical symptoms, medication intake, and immunological parameters. Clinical samples including nasopharyngeal (NP) swabs, induced sputum and stool specimens were collected from all patients, and routine clinical evaluations were performed. Three staining techniques were conducted to enhance diagnostic accuracy and determine the most sensitive method for detecting Cryptosporidium oocysts. The DNA recovery was optimized by freeze/thaw cycling, bead beating and sonication pretreatment. Among 100 patients, the presence of Cryptosporidium spp. was confirmed in 9 cases (9 stool, 3 sputum, and 3 NP samples), using the Nested PCR-RFLP technique. Two Cryptosporidium species were identified: 5 cases of Cryptosporidium hominis and 4 cases of Cryptosporidium parvum. The phylogenetic tree was constructed using sequencing data and was compared against genotypes available in GenBank. Data were analyzed using SPSS statistical software version 19 and analysis of variance (ANOVA test). We found that age, educational attainment, and adherence to treatment had significant relationships with opportunistic infections incidence (P < 0.01). Patients with HIV who had a CD4+ T cell count < 200 cells/µL were more susceptible to developing opportunistic infections (P < 0.001). Furthermore, HIV-positive patients with cryptosporidiosis exhibited significantly higher frequencies of weight loss and gastrointestinal symptoms.