A single dose of intramuscularly administered dexamethasone acetate is as effective as oral prednisone to treat asthma exacerbations in young children.

OBJECTIVE: To evaluate whether a single dose of intramuscularly administered dexamethasone acetate (IM Dex) was as safe and effective as a 5-day course of oral prednisone (PO Pred) in the treatment of young children with mild-moderate exacerbations of asthma. STUDY DESIGN: A prospective, randomized, investigator-blinded study was done in a tertiary care medical center in children (6 months to 7 years of age) who required corticosteroids to treat mild-moderate asthma exacerbations as outpatients. Patients were randomized to receive either a single dose of IM Dex ( approximately 1.7 mg/kg) or PO Pred ( approximately 2 mg/kg/d for 5 days). Clinical asthma score, behavioral changes, albuterol use, and tolerance of the medication were recorded in a home diary for 7 days. Cortisol/creatinine ratios on first morning void urine samples were obtained on day 14. The primary outcome measures were changes in clinical asthma score through day 5 and tolerance of the medication. RESULTS: Fifteen patients in the IM Dex group (mean age 37 months) and 17 in the PO Pred group (mean age 36 months) completed the study. Clinical asthma score improved significantly in both groups during the first 5 days of therapy, and no significant difference was seen in the rate of improvement between the 2 groups. Three children refused more than 75% of their prednisone doses, and another 4 missed 30% to 50% of the doses despite their parents' best efforts. The intramuscular injection caused no complications, and approximately 70% of parents in both groups stated that they would choose IM Dex to treat their child's next asthma exacerbation. CONCLUSION: In this group of children a single intramuscular injection of dexamethasone acetate was as effective as a 5-day course of PO Pred for the management of mild-moderate outpatient asthma exacerbations.

Allergy history does not predict skin test reactivity in asthmatic children.

We prospectively assessed how well patient report of allergy to cat, dust mite, and grass predicted the results of skin prick testing to those allergens in 95 asthmatic children. Children between 4 and 18 years old with physician-documented asthma provided a detailed standardized allergy history and then underwent skin prick testing. The children were categorized by asthma severity. The diagnostic accuracy, which was the primary outcome measure, as well as sensitivity, specificity, and positive and negative predicted values were calculated for allergy history with regards to skin test reactivity. The diagnostic accuracy of allergy history in identifying skin test reactivity was 65%, 50%, and 56% for cat, dust mite, and grass, respectively. Asthma severity did not affect the diagnostic accuracy. Allergy history was a poor predictor of skin test reactivity in this group of asthmatic children.

Ring 22 duplication/deletion mosaicism: clinical, cytogenetic, and molecular characterisation.

A patient with several features consistent with duplication of 22q11.2 (cat eye syndrome or CES) was found to be mosaic for a dicentric double ring chromosome 22 on postnatal karyotyping of peripheral blood. The initial karyotype was 46,XX,r(22)(p12q13) [46]/46,XX,dic r(22)(p12q13; p12q13)[4]. The amount of material duplicated in the dic r(22) was determined to include and extend beyond the CES critical region into 22q13.3. However, karyotyping of lymphocytes and fibroblasts, at 27 and 13 months of age respectively, showed no dic r(22) present in any of the cells examined. We suggest that the CES features in this patient, and potentially in other ring cases with CES phenotypic features, might result from a high level of mosaicism for a dic r(22) during early fetal development. Usually this unstable dic r(22) is subsequently lost from most cells.

Evaluation of heliox in children hospitalized with acute severe asthma. A randomized crossover trial.

STUDY OBJECTIVE: To determine whether breathing a blend of 70% helium:30% oxygen (heliox) would improve pulmonary function, decrease clinical score, and improve the sensation of dyspnea in children hospitalized with acute severe asthma. DESIGN: Prospective, randomized, double-blind, crossover study. SETTING: The inpatient pediatric service of a military, tertiary care, teaching hospital. PATIENTS: Children 5 to 18 years who required hospital admission for treatment of acute asthma. INTERVENTIONS: All patients received 5 mg of nebulized albuterol every 1 to 4 h, with a dose given within 30 min of the start of the study, and IV administered methylprednisolone. Patients breathed heliox and a 30% oxygen-enriched air mixture for 15 min each in random order. MEASUREMENTS AND RESULTS: Clinical score, dyspnea score, oxygen saturation, heart rate, and respiratory rate, followed by FVC, FEV1, peak expiratory flow rate (PEFR), and, mean midexpiratory flow rate (FEF25-75) were obtained at study entry, 15 min after breathing the first gas mixture (heliox or air per randomization), 15 min after breathing the second mixture, and again 15 min after stopping the second gas mixture (study end values). Eleven children were enrolled, and all completed the study. There were no significant differences between study entry and study end spirometric values. Using the paired t test, we found no significant differences between mean values (SD) of FEV1 and FVC obtained while breathing heliox vs air; FEV1-heliox, 53% (18%) of the predicted value; FEV1-air, 52% (16%) of the predicted value (p = 0.36); FVC-heliox, 69% (22%) of the predicted value; and FVC-air, 70% (21%) of the predicted value (p = 0.50). The differences in values for PEFSR and FEF25-75 while breathing heliox vs air were small but did reach statistical significance in favor of heliox: PEFR-heliox, 56% (20%) of the predicted value; PEFR-air, 50% (16%) of the predicted value (p = 0.04); FEF25-75-heliox, 32% (13%) of the predicted value; and FEF25-75-heliox, 29% (11%) of the predicted value (p = 0.006). Heliox had no effect on either clinical or dyspnea scores. CONCLUSION: The short-term inhalation of heliox did not benefit this group of children hospitalized with acute, severe asthma.