Sickle cell anemia. Pathophysiological role of increased intracorpuscular calcium and changes during treatment with...

In a group of 20 homozygous (SS) sickle cell patients (age range 8-28 years) determinations of red blood cell and platelet calcium as well as platelet aggregation and platelet malondialdehyde formation were performed before and after oral treatment with 28.4 mg/kg daily pentoxifylline (Trental) for 30 days. After a previous observation period, drug treatment was started at the onset of painful exacerbation, which thereby subsided within 26.4 +/- 9.6h; no further pain symptoms were observed during the treatment. All the above mentioned parameters were found to be increased before treatment when compared to normal subjects and they fell progressively during treatment: red blood cell calcium 86.0 +/- 17.9 mumol/l (before), 45.0 +/- 8.2 mumol/l (after); intraplatelet calcium 31.6 +/- 10.5 mumol/10(9) platelets (before), 18.0 +/- 5.2 mumol/10(9) platelets (after); malondialdehyde 18.6 +/- 8.9 mumol/10(9) platelets (before), 9.3 +/- 3.9 mumol/10(9) platelets (after). Also platelet aggregation index was significantly reduced. It is concluded that clinical improvement of patients was attributable to the effects of pentoxifylline on both red blood cells and platelets.