Practical use of investigations in patients with hematuria

The majority of patients with microscopic hematuria undergo a complete evaluation resulting in negative findings. The outcome of patients with hematuria was analyzed in an effort to optimize the use of investigations.

The records for 404 patients who presented with hematuria were reviewed. Data were collected on demographics, type of hematuria, investigations, and final diagnosis.

The hematuria was microscopic in 140 patients (35%) and gross in 264 patients (65%). In gross hematuria patients, 10% had urinary tract tumors and 12% had calculi. All patients with genitourinary tumors and 87% of patients with calculi had gross hematuria and/or > or =5 RBCs/HPF (red blood cells per high-power microscopic field) on urinalysis. The sensitivity and specificity were 94% and 6% for the dipstick urine test, 37% and 71% for urine cytology, 92% and 93% for computed tomography (CT), 50% and 95% for ultrasound scans, and 38% and 90% for intravenous pyelography, respectively. Logistic regression analysis showed that age and number of RBCs/HPF in the urinalyses were the only significant factors predicting genitourinary cancer. In patients < or =40 years old, there was one patient with malignancy and seven patients with stones. In older patients, there were 31 patients with malignancy and 32 patients with stones.

Patients with <5 RBCs/HPF on three urinalyses are unlikely to have significant pathology and could possibly be followed up conservatively. Patients < or =40 years of age should have a noncontrast CT or ultrasound study if they present with microscopic hematuria, and a cystoscopy should be added if gross hematuria exists. In older patients, a pre- and postcontrast CT and a cystoscopy should be performed.