Hepatic Fibrosis as a Consequence of Iron Overload in Pyruvate Kinase Deficiency

Abstract

Pyruvate kinase deficiency, which results in a non-spherocytic hemolytic anemia, can be associated with secondary hepatic iron overload and fibrosis (1). We describe a patient with pyruvate kinase deficiency heterozygous for the H63D mutation in HFE who developed hepatic iron overload with advanced fibrosis. A 21-year-old female presented with abdominal pain, scleral icterus, and jaundice. She was diagnosed with pyruvate kinase deficiency at birth, received multiple blood transfusions, and had a splenectomy at age 5. Current laboratory studies revealed a hemoglobin of 6.8 g/dL, a ferritin of 5101 ng/mL, and a transferrin saturation of 100%. Liver enzymes, bilirubin, and LDH were also elevated (Table 1). Tests for viral hepatitis, alpha 1 antitrypsin, ceruloplasmin, AMA, and ANA were negative. A CT of the abdomen showed a homogeneous liver. Liver biopsy revealed massive iron overload and bridging fibrosis (Figure 1). Chelation therapy with deferoxamine was initiated to reduce hepatic iron stores, hoping to prevent progression to cirrhosis. Chelation resulted in improvement in ferritin, liver enzymes, bilirubin, and LDH levels at 24 months (Table 1).Figure 1Table 1: Hemoglobin, Ferritin, Transferrin Saturation, Liver Enzymes, Total Bilirubin, and LDH at Baseline and 24 Months Post-Deferoxamine TherapyIron overload is commonly described in thalassemia, but less frequently in pyruvate kinase deficiency. Salem et al. described a patient with iron overload and cirrhosis in pyruvate kinase deficiency (2). Liver iron concentrations above a critical threshold of 350-400 mumoles/g can cause hepatocellular damage (3). Chelation has been shown to reduce iron overload in pyruvate kinase deficiency (4). Alternative therapies are important for non-responders to chelation who have not progressed to cirrhosis. One group reported successful bone marrow transplantation in a child with pyruvate kinase deficiency (5). Gene targeting and liver transplant may be options in secondary iron overload, and warrant further investigation.