Risk factors of bronchial hyperresponsiveness in children with wheezing-associated respiratory infection

Bronchodilator-responsive bronchiolar obstruction in term neonates: a case series

BACKGROUND

Bronchiolar obstruction, which causes airway obstruction in hyperresponsive airways, often results from the contraction of the airway's smooth muscles, increased viscid mucous secretions, and mucosal oedema consequent upon a reduced cyclic 3,5-adenosine monophosphate (c-AMP). These processes respond to bronchodilators. The six cases presented to us, in Edward Francis Small Teaching Hospital (EFSTH), Banjul, The Gambia, in the newborn period with clinical features suggesting obstruction with airway reactivity with response to bronchodilator treatment are presented here. Our capacity-limited literature search did not show any such report in neonates. This report highlights the need for this condition to be sought in neonates, medically managed in resource-poor countries without resorting to high-cost equipment use, and for its possible future classification.

CASE PRESENTATION

We report six cases of Gambian neonates consisting of four males and two females ages 2-27 days who presented to us with histories of fast breathing of a few hours duration and expiratory respiratory distress. All were term babies with rhonchi and demonstrable prolonged expiration with terminal effort. They all had a diagnosis of hyperreactive airway disease with bronchiolar obstruction. Five cases were first-time wheezers, while one was a recurrence. All were eventually treated with bronchodilators and steroids with good results. The median duration for resolution of most symptoms with treatment was two days, with a range of 1-5 days.

CONCLUSION

Clinically determined bronchiolar obstructions in term neonates can be relieved with bronchodilators and steroids, and this treatment modality, if employed where the pathological process can be established, can reduce the demand on scarce resources in resource-poor countries.

Association of breastfeeding with tidal breathing analysis in infants with bronchiolitis

BACKGROUND

Tidal breathing flow-volume (TBFV) analysis provides important information about lung mechanics in infants.

AIM

To assess the effects of breastfeeding on the TBFV measurements of infants who recover from acute bronchiolitis.

METHODS

In this cross-sectional study, TBFV analysis was performed in infants with bronchiolitis prior to hospital discharge. The ratio of time to peak expiratory flow to total expiratory time (tPEF/tE) at baseline and after the administration of 400 mcg salbutamol was evaluated.

RESULTS

A total of 56 infants (35 boys), aged 7.4 ± 2.8 mo, were included. Of them, 12.5% were exposed to tobacco smoke and 41.1% were breastfed less than 2 mo. There were no differences in baseline TBFV measurements between the breastfeeding groups; however, those who breastfed longer than 2 mo had a greater change in tPEF/tE after bronchodilation (12% ± 10.4% vs 0.9% ± 7.1%; P < 0.001). Moreover, there was a clear dose-response relationship between tPEF/tE reversibility and duration of breastfeeding (P < 0.001). In multivariate regression analysis, infants who breastfed less (regression coefficient -0.335, P = 0.010) or were exposed to cigarette smoke (regression coefficient 0.353, P = 0.007) showed a greater change in tPEF/tE after bronchodilation, independent of sex, prematurity, and family history of asthma or atopy.

CONCLUSION

Infants who recover from bronchiolitis and have a shorter duration of breastfeeding or are exposed to cigarette smoke, have TBFV measurements indicative of obstructive lung disease.

Prevalence, Risk Factors and Cutoff Values for Bronchial Hyperresponsiveness to Provocholine in 7-Year-Old Children

Background

A US Food and Drug Administration (FDA)-approved drug methacholine chloride (Provocholine^®) was recently introduced to Korea where it is now widely used in clinical practice. We aimed to evaluate the prevalence, risk factors and cutoff value of bronchial hyperresponsiveness (BHR) to Provocholine in 7-year-old children.

Methods

Six hundred and thirty-three children from the Panel Study on Korean Children who visited 16 regional hospitals were evaluated. Skin prick tests, spirometry and bronchial provocation tests for Provocholine as well as a detailed history and physical examinations were performed. The bronchial provocation test was reliably performed on 559 of these children.

Results

The prevalence of ever-diagnosed asthma via medical records was 7.7%, and that of current asthma (wheezy episode in the last 12 months + diagnosed asthma by physicians) was 3.2%. The prevalence of BHR to Provocholine was 17.2% and 25.8%, respectively, for a PC20 < 8 and < 16 mg/mL. The risk factors for BHR (PC20 < 16 mg/mL) were atopic dermatitis diagnosis and current dog ownership, whereas those for current asthma were allergy rhinitis diagnosis, a history of bronchiolitis before the age of 3, recent use of analgesics/antipyretics and maternal history of asthma. The BHR prevalence trend showed an increase along with the increased immunoglobulin E (IgE) quartile. The cutoff value of PC20 for the diagnosis of current asthma in children at age 7 was 5.8 mg/mL (sensitivity: 47.1%, specificity: 87.4%).

Conclusions

BHR to Provocholine (PC20 < 8 mg/mL) was observed in 17.2% of 7-year-olds children from the general population and the cutoff value of PC20 for the diagnosis of current asthma was 5.8 mg/mL in this age group. The risk factors for BHR and current asthma showed discrepancies suggesting different underlying mechanisms. Bronchial provocation testing with Provocholine will be a useful clinical tool in the future.

Passive smoking as a risk factor of anemia in young children aged 0-35 months in Jordan

Background

Passive smoking unfavorably affects pregnancy, child birth and child health. Passive smoking associates with still-birth, premature birth as well as acute respiratory infection, asthma, disorder in red blood cell metabolism in children. This study examined the effects of passive smoking on anemia in young children in Jordan.

Methods

The analysis based on the information from 740 children aged 0–35 months that were tested for hemoglobin levels included in the 2002 Jordan Population and Family Health Survey. This study used multivariate logistic regression method to analyze the effect of passive smoking on anemia in young children in Jordan, controlling for a number of risk factors and confounding factors for anemia.

Results

Results indicated that independent of other risk factors and confounding factors, anemia in young children was strongly positively associated with exposure to passive smoking from both parents (OR= 2.99, p < 0.01). Severely undernourished children were at higher risk of anemia independent of passive smoking and other risk factors (OR= 5.29, p < 0.05). Children age 24–35 months, children born to mothers age 35–49, and children lived in households with a hygienic toilet facility were less likely to suffer from anemia.

Conclusion

Passive smoking from both parents was strongly positively associated with anemia in young children in Jordan independent of other risk factors and confounding factors. The results support the importance of smoking prevention during and after pregnancy that prevent childhood anemia and others morbidities in young children.