Massive Hepatomegaly Secondary to Amyloidosis with Normal Liver Chemistries

Amyloid light chain (AL) amyloidosis is a disease of misfolded, fibrous proteins, either kappa or lambda subtype, that can be deposited into one or more organs, caused by a proliferation of plasma cells. The liver is uncommonly the main organ system affected and rarely the only organ affected by amyloid deposition. With hepatic involvement, the most common presenting findings are hepatomegaly and elevation of serum alkaline phosphatase. We report a case of a 50-year-old male who presented to our gastroenterology clinic with marked hepatomegaly secondary to hepatic amyloidosis, in concert with bone marrow involvement and nephrotic syndrome. Biopsies in conjunction with Congo red staining demonstrated 95% replacement of hepatic structure and 80% replacement of bone marrow with amyloid deposition. Despite these findings, liver chemistries, renal function, and blood count were normal. Our case presents not only the rare finding of primary hepatic amyloidosis but also an atypical presentation of this disorder. Although rare, AL amyloidosis should be in a differential diagnosis of any patient who presents with unexplained hepatomegaly, nephrotic-range proteinuria, heart failure with preserved ejection fraction, fatigue, weight loss or a history of monoclonal gammopathy of undetermined significance.