Metabolic Liver Diseases

Wilson's Disease - Copper Chaos Conundrum

• Etiology: Autosomal recessive; ATP7B gene mutation → impaired copper excretion.
• Pathophysiology: Copper accumulates: liver, brain, cornea, kidneys.
• Clinical Features:
  • Liver: Hepatitis, cirrhosis, acute liver failure.
  • Neuropsychiatric: Parkinsonism, dysarthria, psychiatric changes.
  • Ocular: Kayser-Fleischer rings, sunflower cataracts.
  • Other: Fanconi syndrome, hemolytic anemia.
• Diagnosis:
  • ↓ Serum ceruloplasmin (< 20 mg/dL).
  • ↑ Urinary copper (> 100 µg/24h).
  • ↑ Hepatic copper (> 250 µg/g dry weight) - Gold standard.
• Treatment: Chelators (Penicillamine, Trientine), Zinc, Liver transplant.

⭐ Low serum ceruloplasmin is a key diagnostic marker, but it can be normal or even elevated in acute liver failure due to Wilson's disease or during an acute phase response.

Hereditary Hemochromatosis - Iron Overload Ordeal

• Autosomal recessive disorder; ↑ intestinal iron absorption & deposition.
• Pathogenesis: Primarily HFE gene mutations (C282Y, H63D) → ↓ hepcidin synthesis → unregulated iron entry into plasma.
• Clinical Triad (Classic): Cirrhosis, diabetes mellitus, skin pigmentation ("Bronze Diabetes").
  • Other organs: Heart (cardiomyopathy), joints (arthropathy, esp. 2nd/3rd MCPs), pancreas, gonads (hypogonadism).
• Diagnosis:
  • ↑ Serum ferritin (>1000 ng/mL highly suggestive).
  • ↑ Transferrin saturation (>45-50%).
  • Genetic testing for HFE mutations.
  • Liver biopsy: ↑ Iron (Perls' Prussian blue stain); quantification of hepatic iron concentration.
• Complications: Hepatocellular carcinoma (HCC), heart failure.
• Treatment: Therapeutic phlebotomy (mainstay); iron chelators (deferoxamine, deferasirox).

⭐ The most common mutation in Hereditary Hemochromatosis is C282Y in the HFE gene; homozygosity for C282Y is found in the majority of clinically affected individuals of Northern European descent.

📌 Mnemonic: "Heavy Fe Element" for HFE gene.

Alpha‑1 Antitrypsin Deficiency - Protein Misfold Peril

• Genetic Basis: Autosomal codominant, SERPINA1 gene mutation (PiZZ most severe).
• Pathophysiology: Misfolded A1AT protein (Z allele) polymerizes, accumulates in hepatocyte endoplasmic reticulum. Results in ↓ A1AT secretion, leading to ↓ lung protection (emphysema) and liver damage.
• Clinical (Liver): Neonatal hepatitis, cholestasis, jaundice. Later: chronic hepatitis, cirrhosis, ↑ hepatocellular carcinoma (HCC) risk.
• Diagnosis: ↓ Serum A1AT levels, phenotype testing (Pi typing), genotype testing.

  ⭐ Liver biopsy in Alpha-1 Antitrypsin Deficiency characteristically shows PAS-positive, diastase-resistant globules within hepatocytes, representing accumulated A1AT protein.

• Management: Supportive care. Liver transplant for end-stage liver disease. Avoid smoking.

NAFLD/NASH - Fatty Liver Fallout

⭐ NAFLD is the hepatic manifestation of metabolic syndrome and is the most common cause of chronic liver disease in Western countries; insulin resistance is a key pathogenic factor.

• NAFLD: Hepatic steatosis; no significant alcohol.
• NASH: Steatosis + inflammation + hepatocyte injury (ballooning).
  • Risk factors: Obesity, T2DM, dyslipidemia, metabolic syndrome.
• Pathogenesis: Insulin resistance key. "Multiple parallel hits" model.
• Dx: Imaging, LFTs (ALT > AST). Biopsy for NASH confirmation.
• Rx: Lifestyle (weight loss 7-10%), manage comorbidities.

High‑Yield Points - ⚡ Biggest Takeaways

• Wilson's Disease: ATP7B defect, copper accumulation, Kayser-Fleischer rings, ↓ ceruloplasmin, ↑ urinary copper.
• Hereditary Hemochromatosis: HFE gene (C282Y), iron overload, ↑ ferritin, ↑ transferrin saturation, Prussian blue.
• Alpha-1 Antitrypsin Deficiency: SERPINA1 (PiZZ), PAS-D positive globules in periportal hepatocytes, cirrhosis & emphysema risk.
• NAFLD/NASH: Linked to insulin resistance & metabolic syndrome; spectrum from steatosis to cirrhosis.
• Galactosemia: GALT deficiency; galactose-1-phosphate accumulation causes liver damage, cataracts, E. coli sepsis.