Background: Renal transplantation is the treatment of choice in patients with end-stage  renal disease. Urinary tract infection (UTI) is one of the most common complications after renal transplantation and it has serious consequences. The aim of this study was assessing UTIs in renal transplanted patients and evaluation of risk factors associated with post-transplant UTI.
Methods: In this prospective study, 173 patients (48 hospitalized patients and 125 outpatients) were enrolled in this study. These renal transplant recipients evaluated for bacterial urinary tract infection in urology research center at Sina Hospital. After collecting urine samples from symptomatic and asymptomatic patients, urinalysis and colony count were performed. Identification of bacteria was performed by routine microbiological tests in the Department of Pathobiology, School of Public Health, Tehran, Iran, in 2011.
Results: UTI was observed in 47 patients and the most prevalent microorganism was Escherichia coli (E.coli) 18(38.2%). Nearly 71% of UTI cases were diagnosed during the first three months post transplantation. Risk factors for post transplant UTI were female gender, age, length of hospitalization and diabetes mellitus. Female patients were more susceptible than males (OR=0.50 and P=0.047) to infection. There were no significant difference between diabetes mellitus and UTI. Most of the isolated bacteria were susceptible to imipenem and resistant to tetracycline and trimethoprim- sulfamethoxazole.
Conclusion: Our study confirmed that bacterial infections remain as the most common infectious complication in the early post-transplant period, and antibiogram rather than empirical treatment is needed to find the best effective antibiotics. Moreover, risk factors such as female gender, increased age and length of hospitalization are predisposing factors to increased urinary tract infection in renal transplantation.