Prevalence of Intestinal Parasitic Infection in Cancer, Organ Transplant and Primary Immunodeficiency Patients in Tehran, Iran

Abstract

Background: Intestinal parasitic infection in immunodeficient patients especially those with impaired cellular<br />immunity, like neoplasia, renal or heart transplant needs careful consideration. The objective of this study is to evaluate<br />the prevalence of intestinal parasites in different group of patients including cancer patients; organ transplants recipients,<br />and primary immunodeficiency patients. Methods: Stool samples from 190 patients including 80 patients with Primary<br />Immunodeficiency, 85 cancer patients and 25 organ transplant recipients were collected; a direct examination with<br />Phosphate buffered saline (PBS) and formalin ether concentration was performed. The DNA was extracted from<br />parasitologically confirmed patients and nested PCR and sequencing was performed and new obtained sequences of<br />Cryptosporidium parvum and Enterocytozoon bieneusi were compared with deposited ones. Results: In general, the<br />prevalence of parasites was 26/80 (32.5%) in primary immunodeficiency, 22/85(25.9%) in cancer group, and 7/25<br />(28%) in organ transplant. The prevalence of intestinal parasitic infections in primary immunodeficiency patients<br />were Blastocystis hominis 13 (16.2%), Giardia lamblia 10 (12.5%), Cryptosporidium 1(1.2%), Chilomastix mesnilii 1<br />(1.2%), Dientamoeba fragilis 1(1.2%). Of 25 organ transplants, 6 (24%) Cryptosporidium sp were found, all of which<br />were confirmed as Cryptosporidium parvum and one case of Microspora in a heart transplant recipient was confirmed<br />as Enterocytozoon bieneusi by PCR sequencing. The predominant intestinal parasitic infection in cancer patients was<br />19 (22.3%) Blastocystis hominis followed by two (2.3%) Giardia lamblia and one Dientamoeba fragilis 1 (1.1%).<br />Conclusion: The high rate of infection with Blastocystis hominis was found in cancer patients especially colorectal<br />cancer patients, so careful consideration should be given by physicians. Cryptosporidium sp was found to be the major<br />cause of parasitic intestinal infection in patients with organ transplant compared to primary immunodeficiency patients;<br />so transplant recipients undergoing immunosuppressive therapy should be considered as a risk group for acquiring<br />microsporidiosis and Cryptosporidium infection.