Diagnosis of TBMN often involves a combination of clinical evaluation, family history, and laboratory tests.
- Urinalysis: Persistent microscopic hematuria is typically the first sign. Sometimes, proteinuria (protein in the urine) may also be detected. - Family History: A detailed family history can reveal a pattern of hematuria or kidney issues, supporting the diagnosis. - Kidney Biopsy: Although not always necessary, a kidney biopsy can confirm the diagnosis by showing the characteristic thinning of the GBM under an electron microscope. - Genetic Testing: Identifying mutations in the COL4A3 or COL4A4 genes can provide a definitive diagnosis.
