Background: Cryptosporidium species are recognized as important gastrointestinal pathogens. This study was conducted to identify the prevalence, clinical manifestations and genotyping of Cryptosporidium spp. in patients with gastrointestinal illnesses (GIs) in western Iran.
Methods: Overall, 1301 fecal samples were collected from patients with GIs referred to the 12 clinical laboratories in Nahavand County, west of Iran. Modified Ziehl-Neelsen staining method was used to identify the oocysts. DNA was extracted from positive samples and Cryptosporidium spp. were characterized by Nested PCR and sequence analysis of the 60-kDa glycoprotein (gp60) gene. Data analysis was performed using SPSS ver. 16.
Results: Prevalence of cryptosporidiosis was 1.3% (17/1301). Cryptosporidium infection was significantly associated with vomiting and nausea (P=0.001, OR=0.013; CI 95%=0.004- 0.044), abdominal pain (P=0.018, OR=0.073; CI 95%=0.008- 0.633) and diarrhea (P=0.001, OR=0.092; CI 95%=0.023- 0.362). Of the 17 isolates typed, 11 belonged to the C. parvum IId subtype family (subtypes IIdA26G1 and IIdA20G1) and six belonged to the C. parvum IIa subtype family (subtypes IIaA15G2R1 and IIaA16G3R1). There was no significant difference between subtype families IIa and IId in occurrence of clinical symptoms (P= 0.75).
Conclusion: Improved hygiene and avoidance of contact with animals and contaminated soil should be advocated to reduce the occurrence of Cryptosporidium infections, especially in children.