Benign familial hematuria
Overview
Thin basement membrane disease (TBMD, also known as benign familial hematuria and thin basement membrane nephropathy) is, along with IgA nephropathy, the most common cause of asymptomatic hematuria. The only abnormal finding in this disease is a thinning of the basement membrane of the glomeruli in the kidneys.
Symptoms
Blood in urine * Hematuria * Strenuous exercise or exertion * Overly exuberant urination of large amounts * Excessive exercise (see Exercise symptoms) * Injury * Vaginal bleeding * Bleeding from ejaculation * Urinary tract infection
Diagnosis
Thin basement membrane disease must be differentiated from the other two common causes of glomerular hematuria, IgA nephropathy and Alport syndrome. The history and presentation are helpful in this regard: * In Alport syndrome, there is often a family history of kidney failure, which may be associated with hearing impairment. Also, males tend to be more affected as Alport syndrome it is X-linked in most cases. * In IgA nephropathy, episodes of frank hematuria are more common, and a family history is less common.
Prognosis
Overall, most people with thin basement membrane disease have an excellent prognosis. Some reports, however, suggest that a minority might develop hypertension. Thin basement membrane disease may co-exist with other kidney diseases, which may in part be explained by the high prevalence of thin basement membrane disease.[
Treatment
Most patients with thin basement membrane disease need only reassurance. Indeed, this disease was previously referred to as "benign familial hematuria" because of its usually benign course. Angiotensin converting enzyme inhibitors have been suggested to reduce the episodes of hematuria, though controlled studies are lacking. Treating co-existing hypercalciuria and hyperuricosuria will also be helpful in reducing hematuria.