Postsplenectomy Erythrocytosis in Hemoglobin Köln Disease

In a family with hemoglobin Köln disease, which is characterized by mild hemolytic anemia, erythrocytosis developed in the index patient after splenectomy for massive splenomegaly. The erythrocytosis may represent a compensatory response to the high oxygen affinity of hemoglobin Köln. This compensatory response may not have been possible before splenectomy because of the rapid sequestration and destruction of erythrocytes in the spleen. (N Engl J Med 288:929–931, 1973). DURING the past several years more than 30 abnormal hemoglobins that lead to hemolysis because of intrinsic instability of the hemoglobin molecule have been described. Of these unstable hemoglobins, the most frequently identified have been hemoglobin H (β₄), occurring predominantly in people of Southeast Asia, and hemoglobin Köln (α₂β₂98 val→met). Hemolytic anemia is the predominant clinical manifestation of the unstable hemoglobins. We have observed, in a patient with hemoglobin Köln disease, the paradoxic development of erythrocytosis after splenectomy for the treatment of unstable hemoglobin hemolytic anemia. Case Report In 1956 a 49-year-old man of German.