CORRELATION OF IN-VITRO ENHANCEMENT OF ERYTHROPOIESIS AND CLINICAL-RESPONSE TO STEROIDS IN DIAMOND-BLACKFAN ANEMIA

To investigate whether the clinical response to steroids in Diamond-Bl ackfan anaemia (DBA) can be predicted in vitro, erythroid cultures fro m six patients was performed. The increment of burst forming unit eryt hroid (BFU-E) and colony forming unit erythroid (CFU-E) derived coloni es had been studied with the in vitro addition of steroids. Our result s showed: 1) a relative insensitivity to low and optimum concentration of erythropoietin (Epo) in cultures, and 2) lower CFU-E and BFU-E col ony formation in all cases studied. (CFU-Es of normal controls/10(5) c ells; were 85.6, BFU-Es 37.8, while the patients' CFU-E were 18.1 and BFU-E 7/10(5) cells with two IU of Epo) with poor or no growth in thre e cases, 3) increment up to 60-110% with in vitro addition of steroids in three cases, 4) high serum Epo levels in all Diamond-Blackfan anae mia patients, and 5) clinical response to steroids in the three patien ts who responded in vitro.