Is Hematuria an Accurate Predictor of Renal Lithiasis?
Patients with flank pain and suspected renal lithiasis are often evaluated for hematuria by dipstick or microscopic urinalysis. Because the presence of hematuria has been labeled an indicator of renal lithiasis, some authors suggest that no further work-up is necessary. However, there is no consensus as to what constitutes hematuria by microscopy or how to proceed with patients who have hematuria and flank pain. Bove and colleagues reassessed the value of hematuria as a predictor of renal lithiasis using a newer computed tomographic (CT) scanner. A total of 267 patients with acute flank pain was referred for unenhanced helical CT scan of the renal system. Before the CT scan, the patients had a urinalysis performed by dipstick or microscopy. The researchers classified hematuria as greater than zero, greater than 1 or greater than 5 red blood cells per high power field. The dipstick urinalysis was positive for hematuria if the appropriate color change occurred. Using the helical CT scan
