ITE 2014 Q113.
A 55-year-old male with diabetes mellitus is found to have asymptomatic
microscopic hematuria. The rest of his urinalysis is negative. He has no
other medical problems and quit smoking 10 years ago. His only medication is
metformin (Glucophage). A urine culture is negative and his renal function
is normal. CT urography is also negative. Which one of the following should
be the next step in the evaluation of his microscopic hematuria ?
A) Urine cytology
C) Nephrology referral
D) Stopping metformin and performing a repeat urinalysis
E) Antibiotic therapy
- Patients with microscopic hematuria should initially be assessed for
benign causes such as urinary tract infection, vigorous exercise,
menstruation, and recent urologic procedures.
- If none of these is found, the next step would be assessing for
renal disease using urine microscopy to look for casts or
dysmorphic blood cells, and checking renal function.
- If the results are negative, CT urography and cystoscopy
should be performed.
- CT evaluates the upper urinary tract for nephrolithiasis and
- Cystoscopy evaluates the bladder for bladder cancer, urethral
strictures, and prostatic problems.
- Urine cytology is less sensitive than cystoscopy for bladder cancer.
- This patient has normal renal function and no signs of renal disease
on the urinalysis other than hematuria, so a nephrology consultation is
not necessary at this time.
- Metformin use is not associated with microscopic hematuria. There is
no role for antibiotics, given the negative urine culture.
Ref: Sharp VJ, Barnes KT, Erickson BA: Assessment of asymptomatic
microscopic hematuria in adults. Am Fam Physician 2013;88(11):747-754.