The presence of calcium oxalate in urine may point towards further evaluation to exclude urinary tract stones. Calcium containing stones are one of the more common renal stones.
This may require a 24 hour urine specimen to determine calcium, phosphorus and uric acid levels,urine culture and serum calcium, phosphorus and uric acid levels. A kidney, ureter and bladder CT scan may also be requested. A review of your diet may also shed some light on these findings.
This may not be an urgent matter however, proper management will be able to prevent any complications later on.
Keep us posted regarding your progress.