The epidemiology of thin basement membrane nephropathy.

The prevalence of this basement membrane nephropathy (TBMN) may be approximated from the known frequencies of glomerular hematuria in the population, and from the prevalence of autosomal-recessive Alport syndrome and its known relationship to TBMN. These approaches confirm that TBMN affects more than 1% (but < 10%) of the population, making it the commonest inherited renal disease, and one of the commonest conditions affecting the kidney after infections, hypertension, and stones. TBMN is the most frequent cause of persistent glomerular hematuria. Although we do not advocate mass screening for hematuria to detect TBMN, we strongly support investigating hematuria that is discovered incidentally. Individuals with TBMN and isolated hematuria should be evaluated initially by a nephrologist and subsequently reviewed by their family doctor. Those with proteinuria, hypertension, or renal impairment are at risk for progressive renal impairment and should by examined carefully for features of Alport syndrome or an additional glomerular or tubulointerstitial lesion, undergo a renal biopsy examination, be treated symptomatically, and be monitored by a renal physician.