The impact of intestinal parasitic infection in renal transplant recipients requires careful consideration in the developing world. However, there have been very few studies addressing this issue in Iran. This study was conducted to determine the prevalence of intestinal parasitic infections in renal transplant recipients in Iran. Stool specimens from renal transplant recipients and control groups were obtained between June 2006 and January 2007. The samples screened for intestinal parasitic infections using direct smear, formalin-ether sedimentation, Sheather's flotation and modified Ziehl-Neelsen staining methods. Out of 150 renal transplant recipients, 33.3% (50), and out of 225 control group, 20% (45) were infected with one or more type of intestinal parasites. The parasites detected among patients included Entamoeba coli (10.6%), Endolimax nana (8.7%), Giardia lamblia (7.4%), Blastocystis spp. (4.7%), Iodamoeba butschlii (0.7%), Chilomastix mesnili (0.7%) and Ascaris lumbricoides (0.7%). Multiple infections were more common among renal transplant recipients group (p < 0.05). This study highlights the importance of testing for intestinal parasites among Iranian renal transplant recipients. Routine examinations of stool samples for parasites would significantly benefit the renal transplant recipients by contributing to reduce severe infections.

Mutations in the rpoB locus confer conformational changes leading to defective binding of rifampin (RIF) to rpoB and consequently resistance in Mycobacterium tuberculosis. Polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) was established as a rapid screening test for the detection of mutations in the rpoB gene, and direct sequencing has been unambiguously applied to characterize mutations. A total of 37 of Iranian isolates of M. tuberculosis, 16 sensitive and 21 resistant to RIF, were used in this study. A 193-bp region of the rpoB gene was amplified and PCR-SSCP patterns were determined by electrophoresis in 10% acrylamide gel and silver staining. Also, 21 samples of 193-bp rpoB amplicons with different PCR-SSCP patterns from RIFr and 10 from RIFs were sequenced. Seven distinguishable PCR-SSCP patterns were recognized in the 21 Iranian RIFr strains, while 15 out of 16 RIFs isolates demonstrated PCR-SSCP banding patterns similar to that of sensitive standard strain H37Rv. However one of the sensitive isolates demonstrated a different pattern. There were seen six different mutations in the amplified region of rpoB gene: codon 516(GAC/GTC), 523(GGG/GGT), 526(CAC/TAC), 531(TCG/TTG), 511(CTG/TTG), and 512(AGC/TCG). This study demonstrated the high specificity (93.8%) and sensitivity (95.2%) of PCR-SSCP method for detection of mutation in rpoB gene; 85.7% of RIFr strains showed a single mutation and 14.3% had no mutations. Three strains showed mutations caused polymorphism. Our data support the common notion that rifampin resistance genotypes are generally present mutations in codons 531 and 526, most frequently found in M. tuberculosis populations regardless of geographic origin.