A 32-year-old man presents with progressive bilateral sensorineural hearing loss and progressive vision changes. Laboratory evaluation reveals persistent hematuria, proteinuria of 1.8 g/day, and serum creatinine of 1.6 mg/dL. Vital signs are stable (BP 138/88 mmHg, HR 82, RR 16, Temp 37°C, SpO2 98%). Kidney ultrasound shows normal-sized kidneys without hydronephrosis. Kidney biopsy demonstrates IgA-negative glomerulonephritis with characteristic GBM splitting and "basket-weave" appearance on electron microscopy. Which genetic mutation is most likely responsible?
- A)CFHR5 (complement factor)
- B)COL4A3 or COL4A4 (type IV collagen)GABARITO
- C)CD103 (integrin-alpha)
- D)TP53 (tumor suppressor)
- E)NPHS1 (nephrin)
Explicação
Alport syndrome is caused by mutations in genes encoding type IV collagen (COL4A3, COL4A4, or COL4A5), primarily affecting basement membranes. Classic triad: progressive hereditary nephritis, sensorineural hearing loss, and ocular abnormalities (anterior lenti... Ver explicação completa e trilha adaptativa →