Prevalence of symptomatic urinary calculi in Kerman, Iran

In a cross-sectional study, we evaluated the prevalence of symptomatic urinary calculi in Kerman, Iran.

A total of 2431 citizens of Kerman were surveyed from September of 2005 to April 2006. The study population was selected by cluster method from 5 different areas, and 100 houses in each area were randomly approached. Questions on the urinary symptoms consisted of flank pain, urogenital pain, dysuria or any difficulty in urination, and alterations in urine color. Individuals with a suspicion of urinary calculi based on their symptoms were evaluated by physical examination, laboratory investigations, and plain abdominal radiography. Ultrasonography and intravenous urography were done if required to confirm the diagnoses.

Of 2431 individuals, 196 (8.1%) had symptoms in favor of urinary calculus diagnosis, of whom 47 (24.0%) had urinary calculi (prevalence of symptomatic urolithiasis was 1.9%). Of the patients, 35 (74.5%) were underweight. Compared to the other participants, the patients with urinary calculus were younger (P = .001) and a larger proportion of them had a positive family history of urinary calculi (14.9% versus 6.5%; P = .02) and were rug weavers and office employees. Dependency on opium and its derivative was significantly more frequent in patients with urinary calculi (25.5% versus 0.2%; P = .001).

This study showed that the prevalence of symptomatic urinary calculi in this hot and dry area is relatively high. According to our findings, the other factors including specific occupations, malnutrition, and substance use may also have influence on the rate of urinary calculus formation. Therefore, to prevention and early treatment of urinary calculi, evaluation of potential predisposing conditions should be considered with special attention to regional factors.