Hereditary spherocytosis misdiagnosed as severe thalassemia for more than two decades: A case report

Abstract

           The patients with hereditary spherocytosis (HS) mostly have mild degree of hemolytic anemia, mild jaundice and splenomegalyand usually respond well to splenectomy. In occasional instances, the diagnosis of HS may be overlooked and delayed for a very long time as in our case. She was a 26-year-old Thai patient who was simply diagnosed as severe thalassemia since childhood because of her typical thalassemicfacy, severe microcytic hemolytic anemia, the prominent splenomegaly and herbirth placewhere various thalassemias and hemoglobinopathies were highly prevalent. She had been treated with regular blood transfusion every two or three months since then. The splenectomy and later cholecystectomy were performed at the age of 9 and 12 years old, respectively. The last blood test showed Hb 9.4 g%, Hct 25.3%, MCV 77.2 fL, MCHC 37.0, RDW 21.5%, hypochromia 1+, microspherocytosis 2+, ferritin 4,142-5,611 ng/mL. With repeated Hb electrophoresis, slightly increased percentage of Hb A₂, 3.7-4.4 %, was the only one abnormality detected. Other blood tests included positive osmotic fragility test, negative direct anti-globulin test. The thalassemia genotype study revealed only alpha-thalassemia-2 (3.7 kb) trait, neither alpha thalassemia-1 nor beta thalassemia genotype was found, therefore the final diagnosis of severe HS with secondary hemosiderosiswas established. The slightly increased percentage of Hb A₂ overlapping thatof beta thalassemia trait was presumably due to severe HS itself. Likewise, the so-called thalassemicfacy in our case was supposedlyfrom the active intramedullary erythropoiesis compensating to severe and chronic hemolysis since birth that could be documented in any case with either severe thalassemia or severe HS.