The bladder must be emptied at the time the collection is to begin and this urine discarded.
There after all urine must be collected until the end of the scheduled time and kept refirgerated during collection. Collect urine with 10 grams of boric acid at the start of collection. Refrigerate urine during collection (critical). Mix the collection well before checking the pH and ensure boric acid tablet is well dissolved: pH should be between-4-7. Send 10.0 mL (mininum) refrigerated in a screw-capped plastic urine container. Record total volume on requisition and specimen labe.
Room Temperature Unacceptable, Refrigerated 14 days
3-4 days Performed Mon, Wed, Fri
The mean urinary citrate excretion rate in patients with idiopathic calcium urolithiasis is significantly lower than that of control groups. Hypocitraturia is common in patients with urolithiasis resulting from renal tubular acidosis and in patients with enteric hyperoxaluria. Citrate excretion is low in renal insufficiency.