Indications for cystoscopy
When the
ultrasound or IVP is negative cystoscopy is recommended in those patients at risk for bladder cancer:
-
Men over the age of 50 and those with
The combination
Cystoscopy is also indicated in the infrequent patient with otherwise unexplained persistent or intermittent gross hematuria.
Unexplained hematuria
If no diagnosis is apparent from the history, urinalysis, radiologic tests, or cystoscopy, then the most likely causes of persistent isolated hematuria are a mild glomerulopathy or a predisposition to stone disease, particularly in young and middle-aged patients.
Glomerular disease
Approximately 50 percent of patients with idiopathic hematuria have a glomerular disease, which is more likely to persist than other causes of isolated hematuria. Up to 86 percent of patients with hematuria persisting for four years have either IgA nephropathy or thin basement membrane disease.
Hypercalciuria and hyperuricosuria
As many as 30 to 35 percent of children with apparently idiopathic hematuria (no proteinuria or infection, negative radiologic evaluation) have hypercalciuria, while 5 to 20 percent of children with recurrent hematuria have hyperuricosuria ; both disorders are often associated with a positive family history (as high as 40 to 75 percent) of stone disease. These children are at increased risk for the future development of kidney stones. Lowering calcium excretion with a thiazide diuretic typically leads to resolution of the hematuria among those with hypercalciuria; a restricted purine diet or the administration of allopurinol commonly eliminates uricosuria and hematuria in those with hyperuricosuria.
Similar findings may be present in adults. Some patients have hypercalciuria or hyperuricosuria (as detected by a 24-hour urine collection, while others have a history suggestive of stone disease without these biochemical abnormalities. Treatment with a thiazide diuretic for hypercalciuria or allopurinol for hyperuricosuria usually leads to disappearance of the hematuria.