Barbara Andreetta

Benefits and risks of anemia correction with recombinant human erythropoietin in children maintained by hemodialysis

Ten children with renal failure (age range 2 years 6 months to 18 years 9 months; median 11 years 10 months), maintained by long-term hemodialysis, had successful correction of their anemia after intravenous administration of recombinant human erythropoietin in a dosage escalating every 2 weeks (75 to 150 to 300 to 450 IU/kg/wk). Mean hemoglobin concentration increased from 6.4 +/- 0.9 to 11.5 +/- 1.0 gm/dl. Blood cell counts used to evaluate the correction of anemia were done after dialysis; this was especially important for children less compliant with water restriction. The higher hemoglobin concentration resulted in improvement of the quality of life, a greater tolerance for physical effort (exercise tolerance doubled and the ventilatory anaerobic threshold increased significantly), correction of some subclinical central nervous system abnormalities detected by evoked potentials testing, and reduction of bleeding time. Few side effects were noted; severe hypertension developed in one patient when postdialysis hematocrit was only 28%, and there were two episodes of hypertransaminasemia with no other evidence of liver dysfunction. We conclude that in children with renal failure the use of recombinant human erythropoietin to correct anemia is safe and strongly advisable, because of the resolution of many of the symptoms correlated with anemia.

10p12.1 deletion: HDR phenotype without DGS2 features

GATA3 gene encodes a transcription factor expressed during thymus, liver, kidney, adrenal gland, central and peripheral nervous systems, placenta and T lymphocytes embryonic development. Mutations of GATA3 cause Hypoparathyroidism, sensorineural Deafness and Renal dysplasia syndrome (HDR). We report the case of a girl with a terminal deletion of the short arm of chromosome 10 (10p12.1-pter), including both HDR locus and the DiGeorge critical region 2 (DGCR2), with HDR phenotype but not DiGeorge syndrome 2 features. The girl developed chronic renal failure during the first year of life, associated with sensorineural hearing loss, facial dysmorphic features and psychomotor development. She had hypodysplastic kidneys and bilateral grade 3-vesicoureteric reflux. Her karyotype was 46,XX,del(10)(p12.1-pter). Quantitative analysis by Real Time PCR on blood DNA confirmed the lack of one copy of GATA3 gene. She underwent renal transplantation at the age of 11. Our patient is the first case with a large deletion of the short arm of chromosome 10 - that certainly involves DGCR2 - with the HDR phenotype but without the clinical features of DGS2. This peculiarity suggests the hypothesis that the mechanisms underlying this syndrome may be more complex. It is therefore possible that DGS2 may be determined by locus heterogeneity.

Familial occurrence of blind-ending bifid and duplicated ureters.

Blind-ending bifid ureter in a girl with urinary tract infection, and a blind-ending duplicated ureter in her younger sister are described. The embryology of this rare anomaly is briefly reviewed.