39 yr old woman with spina bifida is being evaluated for microscopic hematuria

39 yr old woman with spina bifida is being evaluated for microscopic hematuria. She has past history of UTIs. But she has been healthy for the last year and not on any new medications. No family history of kidney disease. BP : 102/60 and the rest of exam is normal.
U/A: 10-15 RBCs/ HPF no casts or crystals and no proteinuria.
ANA, ANCA, and complement all normal.
Calcium: creat ratio is 0.9 ( normal <0.2).
CT urography : shows 1 normal appearing kidney with no evidence of obstruction.
Urine culx: returns with no growth.

Which of the following is the best management strategy at this time?
A. Perform kidney biopsy.
B. Empirically treat with antibiotics.
C. Encourage high fluid intake, limit sodium intake.
D. Start oxybutynin to prevent bladder spasm.
E. Perform intravenous pyelography.