Purpose: To conduct a study to assess the association between calculus location and size and the incidence of both microhematuria and symptoms of urolithiasis in a urology office environment.
Patients and methods: After Institutional Review Board approval, a prospective study was conducted with data from 100 consecutive patients who presented to our office with documented urolithiasis. The location (caliceal, pelvic, or ureteral) and size (<or ≥ 8 mm) of each calculus was determined from available diagnostic radiographs. The incidence of microhematuria was ascertained via a urine dipstick and microscopic examination. The presence of any symptoms associated with urolithiasis, including pain, subjective fever or chills, or urinary urgency, was recorded.
Results: A total of 111 stones were found in the study population resulting in a 45.9% incidence of microhematuria. In patients with renal pelvic and ureteral stones, 67.6% demonstrated microhematuria vs 36.4% with caliceal stones, P=0.0035. For stones ≥ 8 mm, 62.5% were positive for microhematuria vs 29.1% of stones <8 mm, P=0.0006. Ureteral or renal pelvic stones caused the most symptoms (70.6%) compared with caliceal stones (16.9%), P=0.0001. In those patients who reported pain associated with urolithiasis, 65.6% had concomitant microhematuria vs 36.8% in those without pain, P=0.0097.
Conclusions: Urinary calculus location and size are associated with the incidence of microhematuria and stone-related symptoms. Pain related to urolithiasis may be a positive predictor for the presence of microhematuria.