Estudios citogenéticos en niños chilenos con leucemia linfoblástica aguda / Cytogenetic studies in chilean children with acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most frequent childhood cancer. The leukemic cells of ALL patients show several well defined numeric and structural chromosomal abnormalities which are universally known for its prognostic implications. We studied a group of 44 children with ALL, to investigate the incidence of chromosome aberrations in ALL, its lymphocyte lineage and some clinical feature associations, ans the finding of non previously described aberrations. A high proportion of patients (79.5 per cent) showed chromosomal abnormalities. Most of them had a pseudodiploid karyotype (46 chromosomes), characterized mainly by a translocation. In relation to chromosome number, 27 percent of them were hyperdiploid with more than 50; 9 percent hyperdiploid between 47 - 50 and 7 percent hypodiploid (less than 46). Among structural aberrations found, were the following recurrent translocations: t(1;19), t(4;11), t(9;22) in 6.8 percent, 9.1 percent and 2.3 percent of cases respectively, all related to an early B immunophenotype. Other translocations found, compromised regions 7q22,9p21 -24. Two new translocations in ALL were found: 8(1;5)(q23;q33), apparently balanced and t(13;21)(q14;q22), unbalanced. Other recurrent structural changes found were: deletion (6q), (7q), (7q), (11q), (12q), inversion (3q), isochromosome (7q), maker chromosomes and double minutes. The distribution of chromosome abnormalities in this group of patients was in agreement with previous reports from other investigators

La anemia de la glomerulonefritis aguda post-estreptocócica / Anemia associated to acute post streptococcal glomerulonephritis

Thirty-three children with post-streptococcal acute glomerulonephritis, age x:8.3 years (range 6-12) were studied prospectively. Mean initial hematocrit (Hct) was 31.6 percent with 90 percent showing Hct under the normal lower limit for this age group. Reticulocyte index (RI) was <0.5 in half of the cases. Serum iron concentration, total iron binding capacity (TIBC) and percentaje of transferrin saturation were normal for this age group although 75 percent of the children had increased serum ferritin levels. At the time of discharge, Hct increased to 35.1 percent but 44 percent still had anemia. Hct increased spontaneously for 105 days stabilizing at 38 percent. Based on Hct changes, 3 groups were defined: Group I (3 individuals): normal upon discharge; Group II (19): partial recovery at discharge, slow recovery stabilizing after 105 days; Group III (11): lower Hct, slower recovery but with RI significantly higher than group II (0.96 vs 0.45 p<0.01). Our data suggest that although hemodilution is present in all, it may be considered the solely factor only in 3 cases (Group I). In group II, evidence of bone marrow depression was indicated by the low RI. On the other hand, the intense anemia that could not be justified only by hemodilution and marrow depression in group II, suggest other pathogenic factors