Background and Aim: Cryptosporidiosis is a parasitic disease caused by protozoan parasite CRYPTOSPORIDIUM and leads to an acute and/or chronic gastroenteritis. The disease appears as a self-limiting infection in immunocompotent person, but it causes a chronic disease and extra-intestinal infection, which finally leading to death in immunocompromised patients. With respect to the prevalence of infected immunodeficient patients worldwide and in Iran, there is a need for modeling cryptosporidiosis in laboratory animals. Materials and Methods: Samples were collected from human and animal stools, centrifuged by Paraseb kit, and smear was prepared and assessed with acid fast staining method. After identification of oocysts, it was separated, and concentrated by sucrose floatation. Balb/c and C57bl/6 mice were immunosuppressed by intraperitoneal dexamethasone injection, the immonusuppression was confirmed by lymphocyte proliferation assay, and finally CRYPTOSPORIDIUM oocysts were orally inoculated into inbred mice. Having proved the infection, the animals were humanely killed and the target organs including lungs, liver, intestine and spleen were collected, stained with hematoxyline & eosine method and examine for histopathological effects of the organism in samples. Results: The results of lymphocyte proliferation assay showed that the C57bl/6 mice were more immunesuppressed than the Balb/c one; which facilitate them to be more susceptible to the infection than Balb/c mice. Therefore, the majority (80%) of C57bl/6 mice infected with CRYPTOSPORIDIUM oocysts and 40% of them died, whereas only 20% of Balb/c mice were infected and none of them died due to infection. No histopathological alterations were observed in H&E stained sections of liver, spleen, lung and intestine in control and test groups. Moreover, no infection was detected in impression smears. Conclusion: This study is the first report of experimental cryptosporidiosis and modeling of infection in immunodeficiency in laboratory animals in Iran. The findings indicated that immunosuppressed C57bl/6 mice were more susceptible to CRYPTOSPORIDIUM infection than Balb/c ones. No extra-intestinal infection was detected in study groups, which may be due to short period of infection in experimental animals.

Background: The main goal of the present study was to develop a new sensitive and specific PCR based method for Identification of CRYPTOSPORIDIUM sp. using novel primers from 18S ribosomal RNA. Cryptosporidiosis in high-risk host groups particularly in neonates and immuno-compromised individuals may result in death. To the best of our knowledge this is the first study regarding develop a new PCR based method to diagnose the cryptosporidiosis in Iran.Methods: A total of 850 human fecal samples from patients clinically suspected to cryptosporidiosis and 100 healthy and diarrheic cattle stool specimens were collected. The simplified formol-ether concentration method was carried out for all samples. They were then examined microscopically by modified Ziehl-Neelsen staining method. Total DNA was extracted by QIA amp DNA stool mini kit. PCR and nested-PCR was carried out by using designed primers.Results: Twenty nine cases of cryptosporidiosis infection in human and 30 samples from cattle microscopically were positive. The described primary and nested PCR method could detect allCRYPTOSPORIDIUM positive samples from human and cattle. Regards to suspected negative samples in primary PCR examination, the Nested PCR could approve two more positive results. Furthermore, Nested PCR analysis was able to detect one more case which was negative in both microscopically examination and primary PCR. Specificity of the test was 100%. Sensitivity of Nested PCR in comparison to our gold standard; microscopy after Ridley concentration modified ziehl-Neelsen, was 100%.Conclusion: Our developed PCR based method by using new primers devised from 18S ribosomal RNA revealed the ability for identification of theCRYPTOSPORIDIUM species such as C. parvum and C. huminis with high specificity and sensitivity.

Aim: This study aimed to investigate the presence of oocyst of CRYPTOSPORIDIUM sp., and egg of soil-transmitted helminths in market vegetables in the north of Iran. Background: Fecal-oral transmission via consumption of contaminated food is the main route of transmission of intestinal parasites. Concerning the high risk of contamination of vegetable with intestinal parasites, raw consumption of crops can enhance the chance of transmission of intestinal parasites. Methods: In this study, we collected 34 pre-washed vegetable samples including spinach, mint, parsley, oregano, chives, savory, radish, coriander, basil and tarragon from local markets in Tonekabon City, North of Iran. All vegetable samples were washed using sterile PBS. Parasitological examinations, including direct examination and staining with Lugol’ s iodine and modified Ziehl– Neelsen were performed on the pellet resulted from the washing process. Results: The findings showed that 14/34 (41. 17%) of collected samples were contaminated with at least one parasite. Eggs of Toxocara sp., Ascaris sp., Fasciola sp., Toxoascaris leonine, Trichuris sp. and Enterobius together with free-living larvae, amoeba cyst, cyst of Entamoeba coli and oocyst of CRYPTOSPORIDIUM sp., were observed among the positive samples. Furthermore, statistical analysis indicated that there was no significant correlation between parasitic contamination of vegetables and seasonal changes. Conclusion: This study signifies that some parasites due to their resistant cell wall usually remain in an environment with the harsh condition and thus, consumption of raw vegetables increases the risk of transmission of them.

Objective: CRYPTOSPORIDIUM parvum is a common protozoan pathogen with worldwide distribution. It localizes on the intestinal cells and prolonged diarrhea in immunocompromised patients. The aim of this study was to estimate the prevalence and the clinical features of enteric cryptosporidiosis in pediatric patients with lymphohematopoietic malignancies. Material & Methods: In this cross-sectional study stool samples were collected from 100 children (67 boys, 33girls) with lymphohematopoietic malignancies who underwent chemotherapy between the ages of 6 months and 17 years (mean age 7.5 years). All of the specimens were examined for the oocysts of C. parvum by modified Ziehl Neelsen (MZN) staining technique and coproantigens of C. parvum by ELISA. Findings: CRYPTOSPORIDIUM infection was detected in 22 patients. 16 (72.7%) of the infected patients were male and 6 (27.3) female. 7 (31.8%) patients were <5 years, 8 (36.4%) 5-10 years and 7(31.8) >10 years old. Parasites were detected in 19/85 (86.4%) patients with ALL, 2 of 5 (9.1%) with AML, and 1 of 10 (4.5%) with NHL. Clinical symptoms were found in 11 (50%) of the patients. We found longer duration of chemotherapy in patients who were positive for CRYPTOSPORIDIUM infection (Mean=2067 days) in comparison to negative group (Mean=258.5 days) (ANOVA, f=2.82, P=0.04).Conclusion: The incidence of CRYPTOSPORIDIUM infection was 22% among pediatric patients with lymphohematopoietic malignancies. We recommend evaluation of these patients with at least two different diagnostic methods in order to prevent possible life threatening outcomes.