Human heme oxygenase-1 deficiency presenting with hemolysis, nephritis, and asplenia

Nita Radhakrishnan1, Satya Prakash Yadav, Anupam Sachdeva

  • 1Department of Pediatrics, Pediatric Hematology Oncology and BMT Unit, Sir Ganga Ram Hospital, New Delhi, India.

Heme oxygenase-1 (HO-1) is a stress-induced enzyme that catalyses the oxidation of heme to biliverdin. The primary deficiency of this enzyme has been shown in HO-1 knockout mice, and is characterized by intrauterine death and chronic inflammation. The first case of human HO-1 deficiency was reported in 1999. Human HO-1 deficiency has been observed to involve the endothelial cells more severely, resulting in hemolysis and disseminated intravascular coagulation. We report another case of human HO-1 deficiency in a young girl with congenital asplenia, who presented with severe hemolysis, inflammation, nephritis, which was refractory to therapy with corticosteroids, cyclophosphamide, and rituximab.

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