Acute liver failure histopathology: A 5-year retrospective study.

BACKGROUND: Acute liver failure (ALF) is a rare, life-threatening disease of diverse etiology. It is defined as severe acute liver injury for fewer than 26 weeks' duration with encephalopathy and impaired synthetic function (international normalized ratio [INR] of 1.5 or higher) in a patient without cirrhosis or pre-existing liver disease. The diagnosis rests mainly on the clinical ground with wide range of pathological features. The present study seeks to explore the diverse histological patterns observed in cases for ALF and assess their usefulness in determining the underlying causes for the condition.

METHODOLOGY: A retrospective cross-sectional study was conducted among patients of ALF who underwent liver transplant and transjugular liver biopsy over a five-year period. From 1082 explant liver and 2446 liver biopsies, 22 cases of ALF (10 explants and 12 liver biopsies) were included in the study. Clinical and laboratory details were retrieved and histological findings were reviewed.

RESULT: Age ranged from 10 to 72 years (mean age, 40 years). There was a female predominance with a male:female ratio of 1:1.7. The commonest cause for ALF was virus-induced hepatocellular damage in 36.3% (eight patients), followed by autoimmune hepatitis in 22.7% (five patients), drug-induced liver injury (DILI) in 18.1% (four patients), cryptogenic in 13.6% (three patients) and ischemic injury secondary to large vein thrombosis in 9.0% (two) patients. The histological patterns identified were categorized into six categories. A more comprehensive morphological evaluation was conducted specifically for cases of ALF associated with autoimmune hepatitis (AIH) and compared with other cases of ALF.

CONCLUSION: In summary, our present study illustrates a morphological overlap in various patterns for the purpose of etiological assessment. In cases of AIH ALF, the presence of portal plasma cell infiltrate and central perivenulitis were identified as significant histological features to guide diagnosis.