Marked Hypervitaminemia B12 Associated With Previously Unrecognized Alcohol-Related Cirrhosis Revealed During Alcohol Withdrawal.

Vitamin B12 deficiency is commonly investigated in clinical practice, particularly in patients with anemia, neurological disorders, or malnutrition. In contrast, elevated serum vitamin B12 levels are less frequently discussed and may be overlooked by clinicians. However, hypervitaminemia B12 has been associated with several underlying conditions, including liver diseases, hematological malignancies, solid tumors, and chronic kidney disease. Liver injury may lead to increased circulating levels of vitamin B12 due to hepatocellular release and altered metabolism of cobalamin-binding proteins. We report the case of a 44-year-old man admitted for planned alcohol withdrawal after a 10-year history of chronic alcohol consumption estimated at 80-100 g of ethanol per day. Physical examination revealed moderate facial couperosis, a sharp inferior liver edge on palpation, and a few spider angiomas without ascites or signs of hepatic encephalopathy. Laboratory investigations showed macrocytosis without anemia, mild thrombocytopenia, moderate hepatic cytolysis, and markedly elevated gamma-glutamyl transferase levels. A significant hypervitaminemia B12 was identified with a serum concentration of 1,124 pg/mL. Additional findings included mild hyperferritinemia, albumin at 32 g/L, and prothrombin time at 75%. Alpha-fetoprotein levels were within the normal range. Abdominal ultrasound demonstrated morphological features consistent with liver cirrhosis without focal hepatic lesions. The patient was classified as Child-Pugh class A, and the FIB-4 score was calculated at 6.2, suggesting advanced liver fibrosis. This case highlights that elevated serum vitamin B12 may represent an important biological marker of underlying liver disease, particularly alcohol-related cirrhosis. Recognition of hypervitaminemia B12 in patients with chronic alcohol consumption should prompt further evaluation for liver disease and may contribute to earlier detection of chronic hepatopathies.