An Elusive Diagnosis: Diffuse Large B-Cell Lymphoma Masquerading as Acute Liver Failure with Persistent Lactic Acidosis.

BACKGROUND Acute liver failure (ALF) associated with malignant lymphoma is a rare condition with non-specific clinical and radiological features. Here, we describe an unusual case of ALF due to DLBCL with an image negative on presentation posing diagnostic difficulty. CASE REPORT A 74-year-old man was admitted to our hospital with abdominal pain. Radiological and laboratory investigations revealed lymphadenopathy with mildly elevated transaminitis and alkaline phosphates levels. A right upper-quadrant ultrasound showed heterogeneous hepatic parenchyma. Eight days later, he had worsening abdominal pain. He was found to have altered mental status and asterixis. His liver function was worsened with ALT 101, AST 328, lactic acid 4.2, total bilirubin 2.5, INR 6.35, and ammonia level 117 µmol/L. He continued to deteriorate with worsening lactic acidosis, coagulopathy, severe anemia, elevated liver enzymes, and thrombocytopenia. Unfortunately, the patient died of multi-organ failure on the 14th day of hospitalization. The autopsy findings revealed DLBCL involving multiple organs, including the liver, lung, bone marrow, and multiple lymph nodes. Despite an extensive diagnostic workup, an underlying diagnosis was unable to be established antemortem. CONCLUSIONS We describe a case of ALF linked to DLBCL discovered at autopsy. The non-specific clinical and radiological features of this condition make diagnosis challenging, and the prognosis is often poor. Further research and awareness are needed to improve the early detection and management of ALF associated with malignant lymphoma. By expanding the literature on this topic, we aim to improve outcomes and optimize patient care in similar clinical scenarios.