Possible Findings: incr. BUN and serum creatinine levels; RBCs, WBCs, pyuria, crystals, casts, minerals, bacteria on urinalysis; incr. uric acid, calsium, phosphorus, oxalate, or cystine values on 24hr urine sample; calculi or anatomic changes on IVP or KUB x-ray; direct visualization of obstruction on cystoureteroscopy