PLATELET-FUNCTION IN PATIENTS WITH SICKLE-CELL-ANEMIA IN NAIROBI

From July 1990 to January 1991 we studied platelet functions in 55 ind igenous Kenyan patients (23 males and 32 females) with sickle cell ana emia (SCA) in steady state (SCASS) and in 20 (11 males and 9 females) SCA patients in vaso-occlusive sickle cell crisis (VSCC). A control gr oup of 50 healthy (23 males and 27 females) individuals matched for ag e and sex was also studied. Platelet aggregation time to ADP in SCASS (57.2 +/- 39.1) and in VSCC (31 +/- 11.1) were more prolonged (p < 0.0 5) compared to controls (12.71 +/- 5.2). It was also significantly mor e prolonged (p < 0.05) in VSCC than in SCASS, Platelet adhesiveness ti me was 31.1 +/- 13.7 seconds in SCASS, 30.9 +/- 11.1 in VSCC, and 37.7 +/- 13.0 in controls and was significantly lower in both SCA groups ( p < 0.05) but there was no significant difference between the two SCA groups themselves. Clot retraction was 52.8 +/- 6.9 in SCASS, 53.6 +/- 10.7 in VSCC, and 45.9 +/- 8 in controls and was significantly higher in both SCA groups than in controls (p < 0.05). There was no signific ant difference between the two SCA groups themselves. We conclude that platelet function is deranged in indigenous Kenyan patients with SCA.