Painful sickle cell crises precipitated by stopping prophylactic exchange transfusions

• Published in: Journal of clinical pathology Vol. 40; no. 5; pp. 505 - 507
• Main Authors: Keidan, A J, Marwah, S S, Vaughan, G R, Franklin, I M, Stuart, J
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and Association of Clinical Pathologists 01.05.1987; BMJ; BMJ Publishing Group LTD
• Subjects: Adult; Anemia, Sickle Cell - blood; Anemia, Sickle Cell - etiology; Anemia, Sickle Cell - prevention & control; Anemias. Hemoglobinopathies; Biological and medical sciences; Blood Viscosity; Diseases of red blood cells; Exchange Transfusion, Whole Blood; Hematocrit; Hematologic and hematopoietic diseases; Hemoglobin, Sickle - analysis; Humans; Male; Medical sciences; Human; Hemoglobinopathy; Sickle cell anemia; Pain; Hemopathy; Exsanguineous transfusion; Crisis
• ISSN: 0021-9746; 1472-4146
• DOI: 10.1136/jcp.40.5.505

A patient with homozygous sickle cell disease showed a reduced incidence of painful crises as a result of regular exchange transfusion, but on three occasions when transfusion treatment was interrupted, a painful crisis occurred. Onset of painful crisis was associated with raised packed cell volume (PCV) or percentage of haemoglobin S (HbS%), or both. Measurement of whole blood viscosity using in vitro mixtures of blood group compatible normal (AA) and sickle (SS) cells showed that above an HbS of 25% any increase in PCV caused a disproportionate increase in whole blood viscosity. These clinical observations and laboratory data suggest that when regular exchange transfusions are terminated both HbS% and PCV should be carefully monitored. Prophylactic venesection should be considered for patients who maintain their PCV after transfusion as HbS% rises.