The prevalence and pattern of congenital anomalies of the urinary tract detected by intravenous urography in Kuwait

Abstract

We conducted a prospective population-basedstudy in Kuwait to determine the prevalence andpattern of previously undiagnosed congenitalanomalies of urinary tract in patientsundergoing intravenous urography (IVU) and toexamine the demographic factors associated withthese anomalies. The study included 2398consecutive patients undergoing IVU, forvarious indications, in all the six publichospitals in Kuwait, during the period 1 June1999–30 September 2000. Patients were alsointerviewed to obtain selected demographicinformation. Multiple logistic regression wasused to identify factors associated with theanomalies. The average age (± SD) of thepatients (1623 males, 775 females) was 39.2± 15.1 years. A total of 335 anomalies(12.1% in males, 17.9% in females;p < 0.001) were detected in 300 (12.5%)patients (10.9% males, 15.9% females; p < 0.01). About half (47.2%) of the anomaliesinvolved the kidney, 28.4% renal pelvis,22.4% ureters, and 2.1% bladder. Multipleregression analysis showed that age < 20 years(odds ratio (OR) = 12.5; 95% confidenceinterval (95% CI): 7.0–22.3) female gender (OR= 1.5; 95% CI: 1.2–2.0) Kuwaiti nationality(OR = 1.7; 95% CI: 1.2–2.3) and family historyof congenital malformation (OR = 3.8; 95% CI:2.2–6.6) were independently associated with theanomalies of the urinary tract. Overall, 42%of the patients reported a consanguineousmarriage between their parents. The frequencyof anomalies was higher in individuals who hadconsanguineous parents (13.8 vs. 11.6%; OR =1.2) but this positive association did notreach statistical significance. Considering therelatively high prevalence of previouslyundiagnosed congenital anomalies of the urinarytract, it is important to establish clinicalguidelines for early detection and managementof these conditions to decrease the associatedmorbidity and mortality.