A 14-year-old boy with progressive hepatomegaly and jaundice presents with chronic hepatitis. Vital signs: BP 118/76, HR 88, RR 16, Temp 37°C, SpO2 98%. Liver biopsy shows PAS-positive, diastase-resistant globules within hepatocytes. Laboratory studies reveal elevated transaminases (AST 156 U/L). He denies alcohol use and has no history of viral hepatitis exposure. Notably, he also has early-onset emphysema. Which mechanism most likely accounts for his liver pathology?
- A)Defective peroxisomal beta oxidation
- B)Failure of ubiquitin conjugation
- C)Misfolded protein retention in the endoplasmic reticulumGABARITO
- D)Lysosomal glycogen accumulation
- E)Microtubule transport defect
Explicação
In alpha 1 antitrypsin deficiency, the mutant protein misfolds and accumulates within the endoplasmic reticulum of hepatocytes. This toxic gain of function injures the liver, while loss of antiprotease activity in the lung predisposes to panacinar emphysema. Ver explicação completa e trilha adaptativa →