en تخصصي Special Short communication Short communication <div style="text-align: justify;"><span style="font-family:Times New Roman;"><span style="font-size:14px;"><span style="line-height:115%"><b><span style="line-height:115%">Background: </span></b><span style="line-height:115%">The intestinal tract of human can be infected by protozoan parasites. In this short communication, the stool samples were collected from patients with diarrhea referred to Kut hospital, Iraq, and then the parasites (<i>Giardia lamblia, Entamoeba histolytica, Cryptosporidium parvum</i>) were considered for molecular identification.</span></span><br> <span style="line-height:115%"><b><span style="line-height:115%">Methods:</span></b> <span style="line-height:115%"><span style="color:black">Stool samples were collected from 69 patients with diarrhea and then transferred to laboratory. Protozoan parasites were evaluated by Polymerase Chain Reaction (PCR) and phylogenetic tree analysis. Small subunit 18S rRNA region was amplified in the sizes of 514 bp, 409 bp, and 507 pb for<i> G. lamblia,</i> <i>E.</i><i> histolytica</i>, and<i> C. parvum</i>, respectively.</span><span style="font-family:&quot;Times New Roman&quot;,&quot;serif&quot;"></span></span></span><br> <span style="line-height:115%"><b><span style="line-height:115%">Results:</span></b> <span style="line-height:115%"><span style="color:black">The results of phylogenetic tree analysis showed that <i>G. lamblia </i>had 99% identity to <i>G. lamblia</i> </span><span style="color:#222222">with accession number of <span style="background:white">DQ157272.1</span></span><span style="color:black"> (and total genetic changes of 0.002%); <i>E. histolytica</i> also had 99% identity to <i>E. histolytica</i> with accession number of GQ423748.1 (total genetic changes of 0.0005%); and <i>C. parvum</i> had 99% identity to <i>C. parvum </i>with accession number of AJ539197.1 (total genetic changes of 0.05%).</span><span style="font-family:&quot;Times New Roman&quot;,&quot;serif&quot;"></span></span></span><br> <span style="line-height:115%"><b><span style="line-height:115%">Conclusion:</span></b> <span style="line-height:115%"><span style="color:black">Gastrointestinal symptoms in the individuals with the studied protozoan parasites can be diagnosed directly by molecular detection and phylogenetic tree analysis with satisfying results. As well as, it can be utilized like a target for therapeutic intervention for these </span></span><span style="background:white"><span style="line-height:115%"><span style="color:#1c1d1e">enteric protozoan</span></span></span><span style="line-height:115%"><span style="color:#1c1d1e">s</span><span style="color:black">.</span></span><br> <br> <b><span style="line-height:115%">DOI:</span></b> <span style="line-height:115%">10.18502/jfqhc.9.4.11378</span></span></span></span></div> Giardia lamblia, Entamoeba histolytica, Cryptosporidium parvum, Phylogeny, Diarrhea, Iraq 234 240 http://jfqhc.ssu.ac.ir/browse.php?a_code=A-10-1531-1&slc_lang=en&sid=1 D.K. Kadhim thalsarrai@uowasit.edu.iq 0000-0003-0832-5419 Yes Department of Anatomy and Biology, Faculty of Medicine, University of Wasit, Wasit, Iraq D.A. Alzubaidi No Wasit Education Directorate, Wasit, Iraq