Hyperbilirubinemia after hematopoietic stem cell transplantation: Comparison of clinical and pathologic findings in 41 autopsied cases

Hyperbilirubinemia is often associated with morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Diagnosis of its etiology is usually made clinically among various possible causes, and analysis of histological findings as compared with the clinical diagnosis has not been performed sufficiently. We retrospectively analyzed clinical and pathological findings in 41 autopsied patients who died with hyperbilirubinemia (>2mg/dL). Overall, liver graft-versus-host disease (GVHD) showed the most prominent discordance between clinical and pathological diagnoses. Only 11 of the 22 patients, considered to have liver GVHD clinically, had GVHD findings at autopsy. Serum gamma-glutamyl transpeptidase (GGT), GGT/aspartate aminotransferase (AST) ratio, and alkaline phosphatase (ALP)/AST ratio in GVHD patients were significantly higher compared with those without GVHD (p=0.02, <0.01, and 0.03, respectively), which was useful in clinical diagnosis of liver GVHD. Other major findings include liver invasion of the primary malignancies in 8 patients, post-transplant lymphoproliferative disorder of the liver in two patients, and disseminated liver invasion by fungus or varicella-zoster virus in one patient, respectively. Although analysis of clinical data is useful for narrowing diagnosis, histological analysis by liver biopsy is crucially important, especially in cases suspected of having GVHD.