Autonomic nervous system functions in children with breath-holding spells and effects of iron deficiency.

AIM: To analyse the activity of the autonomic nervous system during breath-holding spells, we assessed the ECG changes, including ventricular repolarization parameters before and during the spell. We also analysed the effects of iron deficiency on these ECG parameters. METHODS: The study group consisted of 37 children with breath-holding spells (30 cyanotic, 7 pallid) (mean age+/-SD: 12.9+/-10.8 mo). Twenty-six healthy children (mean age+/-SD: 14.4+/-8.6 mo) served as a control group. All patients and controls had standard 12-lead simultaneous surface ECG. All patients had ECG recordings during at least one severe breath-holding spell obtained by "event recorder". Traces obtained by "event recorder" were analysed in terms of mean heart rate and the frequency and duration of asystole during the spell. RESULTS: Respiratory sinus arrhythmia on standard ECGs and asystole frequency during spells were higher in patients with pallid breath-holding spells. Patients with iron deficiency had a lower frequency of respiratory sinus arrhythmia and prolonged asystole time during the spell. There was no difference in terms of ventricular repolarization parameters (QT/QTc intervals and QT/QTc dispersions) between patients and controls and between patient subgroups (cyanotic versus pallid). CONCLUSION: These results confirmed the presence of autonomic dysregulation in children with breath-holding spells. Iron deficiency may have an impact on this autonomic dysregulation. Ventricular repolarization was unaffected in patients with breath-holding spells.

Granulocyte transfusions in children with chronic granulomatous disease and invasive aspergillosis.

The transfusion of granulocytes to restore host defenses in severely granulocytopenic patients or in patients with defective granulocyte functions has been studied for more than 60 years. However, inadequate dosage of cells and inconsistent efficacy has limited the usage of these transfusions. Recently, the use of mobilizing agents such as granulocyte colony stimulating factors and dexamethasone has renewed interest in these treatment modalities. The present study is conducted to determine an appropriate method of enriched granulocyte collection with Fresenius AS.TEC.204 cell separator (Fresenius, Bad Homburg, Germany) and to evaluate the preliminary clinical results of granulocyte transfusion therapy in patients with chronic granulomatous disease and invasive Aspergillosis in parallel with in vitro granulocyte function. Three patients who have been treated for chronic granulomatous disease and invasive Aspergillosis received a total of 20 granulocyte transfusions. To mobilize granulocytes, healthy donors were given 450 microg of granulocyte colony-stimulating factor (G-CSF) subcutaneously and 8 mg of dexamethasone orally approximately 12 h before collection. Five microg/kg/day of G-CSF was also subcutaneously administered prior to granulocyte transfusions. The first patient received 4; the second, 14 and the third, 2 transfusions. The granulocyte count given to these patients ranged between 0.4 and 3.0 x 10(9)/kg. Most transfusions were well tolerated. The nitroblue tetrazolium (NBT) tests that were done 16-24 h after the transfusion showed 14-46% dye reduction. Two of the three patients survived the infection. Granulocyte transfusions from G-CSF and dexamethasone stimulated donors could be a choice of treatment in chronic granulomatous disease patients, especially with disseminated invasive Aspergillosis.

Peripheral blood lymphocyte subsets in healthy Turkish children.

Immunophenotyping of peripheral blood lymphocyte subpopulations is essential for the diagnosis and follow-up of children with immunodeficiencies and other immune disorders. The relative size and absolute number distributions (median and 5-95%) of lymphocyte subsets, including cord blood (Coulter, EPICS-XL) were examined by flow cytometry in 190 healthy subjects from birth to 18 years of age with a view to obtaining normal reference values for Turkish children of the following age groups: cord blood (n:29), birth to 1 year (n:41), 1 to 2 years (n:30), 2 to 6 years (n:30), 6 to 10 years (n:30), and 10 to 18 years (n:30). The relative size of CD2+, CD3+CD16-56-, CD3+CD8+ T lymphocytes increased while the relative size and absolute counts of those together with CD3+CD4+ and CD19+, CD20+ B lymphocytes decreased with age. The percentage of CD3-CD16+56+ NK cells increased from 0-1 year to 10-18 years; however, absolute count of CD3-CD16+56+ NK cells remained stable and unchanged in all age groups. The relative size and absolute count of activation markers (CD3+CD25+ and HLADR+) decreased from 0-1 year through 10-18 years age group. This study has once more demonstrated that both the percentage and the absolute number of lymphocyte subsets in cord blood and peripheral blood of healthy infants and children changed with age. Therefore, comparison of results to those of age-matched healthy controls is of utmost importance in the reliable and accurate evaluation of lymphocyte subsets reflecting cellular immunity in children.

Evaluation of erythropoiesis by serum transferrin receptor and ferritin in infants aged 0-6 months.

The aim of this study was to evaluate erythropoiesis in 198 healthy babies aged 0-6 months by determination of their blood count, serum transferrin receptor (STfR), and ferritin levels. Anemia and microcytosis were present in 9% and 13% of the sample, respectively. Microcytosis rate was as high as 45% in 6-month-old babies. In infants with normal blood counts, the values of sTfR/ferritin and sTfR-F index were increasing with the increase of sTfR and decrease of ferritin beginning from 2 months of age. In the 5- to 6-month-old group, sTfR concentrations, sTfR/ferritin ratio, and sTfR-F index were higher in infants with anemia and microcytosis. This research showed a high frequency of iron deficiency detected in otherwise healthy babies. Only problems with early weaning practices were found to be significantly more common in babies with iron deficiency.