Cytoplasmic inclusion bodies and minimal hepatitis: Fibrinogen storage without hypofibrinogenemia

A 12-year-old Japanese boy had chronic elevation and fluctuation of serum t ransaminase levels since infancy, sith no signs or symptoms of liver failur e. Usual infections or metabolic disorders were eliminated from considerati on. No coagulopathy or abnormality in plasma concentrations of clotting fac tors was found. Light microscopy of liver biopsy specimens obtained at ages 2, 5, and 7 years showed slight hepatocyte disarray and minimal mononuclea r-leukocyte lobular inflammation, with eosinophilic inclusion bodies in the cytoplasm of hepatocytes throughout the lobule. These bodies stained with the periodic acid-Schiff (PAS) technique; the PAS-positive material was par tly diastase digestible and on immunostaining marked for fibrinogen but not for alpha (1)-antitrypsin. On transmission electron microscopy, the bodies were represented by finely granular material contained within membranes an d were interpreted as tentatively: endoplasmic reticulum. Fibrinogen storag e may be manifest as minimal hepatitis without coagulopathy.