Publication

Abstract : Forty-seven children with chronic myelogenous leukemia (CML) were analyzed for BCR-ABL messenger RNA (m-RNA) at presentation. The BCR-ABL mRNA junctions b2a2 and b3a2 were amplified by reverse transcription polymerase chain reaction. The 2 junctions were identified by their different banding pattern on agarose gel electrophoresis. The 239 bp reverse transcription polymerase chain reaction product is the band specific for b3a2 mRNA, whereas 164bp reverse transcription polymerase chain reaction product is specific for b2a2 mRNA. Clinical and hematological features at diagnosis are given in Table 1a, Table 1b. In our study, the median age of patients was 13.2 years (range 0–18 years) with male preponderance (M:F = 2:1). Among children, the prevalence of CML was found to be highest (66%) in those older than 15 years, unlike Millot et al. [1] who reported a low prevalence (20%). Of the 47 patients, 32 (68%) had b2a2 and 15 (32%) had b3a2 type of transcript, which is at variance to an earlier study [1] that reported 37.5% b2a2 and 26.5% b3a2 but is similar to Auer's study [2] that also has reported high prevalence of b2a2. The median white blood corpuscles count (116×109/L) in this study, was lower than that reported by Millot et al. but was comparable to other studies [2], [3]. In children (93%) massive splenomegaly and high total leucocyte count at presentation (p<0.01) was observed, which is in concordance to earlier reports [1]. Anemia was the predominant characteristic in children with CML, as the majority of them had hemoglobin <11g/dL. There was no correlation found between hemoglobin concentration and splenomegaly at diagnosis (p>0.01). Previous studies [4], [5] have reported that b3a2 transcript is associated with higher prevalence of thrombocytosis. However, in our study only 16 patients (34%) showed thrombocytosis, which is significantly, lower than reported earlier [1]. Thus, it appears that thrombocytosis may be one of the factors accounting for lower frequency of b3a2 transcript in our population.