Alport Syndrome - Usmle case based discussion

📌 𝐅𝐨𝐥𝐥𝐨𝐰 𝐨𝐧 𝐈𝐧𝐬𝐭𝐚𝐠𝐫𝐚𝐦:-   / drgbhanuprakash   📌𝗝𝗼𝗶𝗻 𝗢𝘂𝗿 𝗧𝗲𝗹𝗲𝗴𝗿𝗮𝗺 𝗖𝗵𝗮𝗻𝗻𝗲𝗹 𝗛𝗲𝗿𝗲:- https://t.me/bhanuprakashdr 📌𝗦𝘂𝗯𝘀𝗰𝗿𝗶𝗯𝗲 𝗧𝗼 𝗠𝘆 𝗠𝗮𝗶𝗹𝗶𝗻𝗴 𝗟𝗶𝘀𝘁:- https://linktr.ee/DrGBhanuprakash alport syndrome is a genetic disorder of the basement membrane, resulting from mutations in genes that encode the alpha- 3, alpha-4, and alpha-5 chains of type IV collagen. The resulting structural basement membrane abnormalities lead to progressive dysfunction of the glomerular filtration barrier, sensorineural hearing loss, and ocular defects. The most common mutation is in the COL4A5 gene, inherited in an X-linked manner. The majority of affected individuals will experience progressive renal insufficiency. The initial manifestation is microscopic hematuria in childhood, which ultimately progresses to proteinuria and glomerular filtration rate decline. Best Tests Renal biopsy revealing longitudinal splitting of the lamina densa on electron microscopy. This is diagnostic but not always present early in the course of disease. Immunostaining of type IV collagen on renal biopsy demonstrating either absence or abnormal distribution of the alpha-3, alpha-4 and/or alpha-5(IV) chains of the GBM is sufficient. Skin biopsy may be used as an alternative, less-invasive diagnostic approach using monoclonal antibody against the alpha-5(IV) chain. If this protein is absent in a male or mosaic in a female, the diagnosis can be made without genetic testing. Confirmatory genetic testing in unclear cases assesses for mutations in the COL4A3 or COL4A4 gene.