About this Medicine article

A new sickle cell disease phenotype associating Hb S trait, severe pyruvate kinase deficiency (PK Conakry), and an α2 globin gene variant (Hb Conakry) by Michel Cohen-Solal; Claude Préhu; Henri Wajcman; Claude Poyart; Josiane Bardakdjian-Michau; Jean Kister; Danielle Promé; Colette Valentin; Dora BAchir; Frédéric Galactéros is a Medicine article available to read on EtoBox.

A Guinean woman, hetererozygous for haemoglobin (Hb) S, was studied because of episodes of marked anaemia, repeated typical metaphyseal painful crises and haemosiderosis. Her sickling syndrome resulted from the association of Hb S trait with a severe pyruvate kinase deficiency leading to a 2,3‐DPG concentration of twice normal levels. Sequence of the PK‐R gene revealed an undescribed mutation in the homozygous or hemizygous state within exon 5 (nucleotide 2670 C → A), leading to the interchange of Ser 130 into Tyr (PK Conakry). In addition, the patient carried a new haemoglobin variant, Hb Conakry [α80(F1) Leu → Val], which seemed to have a mild effect. The high intraerythrocytic 2,3‐DPG concentration induced by the PK deficiency resulted in a decreased oxygen affinity which favoured sickling to a level almost similar to that of Hb S/C compound heterozygous patients. This was confirmed by oxygen binding measurements of Hb A/Hb S erythrocytes in which 2,3‐DPG content was modified __in vitro__. Hysteresis between deoxy‐ and reoxygenation curves, as well as increase in the __n__~max~ value, demonstrated that the extent of HbS polymerization in the propositus was almost the same as th

Author

Michel Cohen-Solal; Claude Préhu; Henri Wajcman; Claude Poyart; Josiane Bardakdjian-Michau; Jean Kister; Danielle Promé; Colette Valentin; Dora BAchir; Frédéric Galactéros

Publisher

John Wiley and Sons; Wiley (Blackwell Publishing); Blackwell Publishing Inc.; Wiley (ISSN 0007-1048)

Published

1998

Language

EN

Field

Medicine (Health Sciences)