Thin Basement Membrane Disease - Diagnosis

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.

A kidney biopsy is the only way to diagnose thin basement membrane disease. It reveals thinning of the glomerular basement membrane from the normal 300 to 400 nanometers (nm) to 150 to 250 nm. However, a biopsy is rarely done in cases where the patient has isolated microscopic hematuria, normal kidney function, and no proteinuria. The prognosis is excellent in this setting unless the clinical manifestations progress, as occurs in most males and some females with Alport syndrome and many patients with IgA nephropathy.