Lower respiratory tract illness (LRTI) is a leading cause of mortality and morbidity in children. Sensitive and noninvasive infant lung function techniques are needed to measure risk for and impact of LRTI on lung health. The objective of this study was to investigate whether lung function derived from the intra-breath forced oscillation technique (FOT) was able to identify healthy infants at risk of LRTI in the first year of life.Lung function was measured with the novel intra-breath FOT, in 6-week-old infants in a South African birth cohort (Drakenstein Child Health Study). LRTI during the first year was confirmed by study staff. The association between baseline lung function and LRTI was assessed with logistic regression and odds ratios determined using optimal cut-off values.Of the 627 healthy infants with successful lung function testing, 161 (24%) had 238 LRTI episodes subsequently during the first year. Volume dependence of respiratory resistance (ΔR) and reactance (ΔX) was associated with LRTI. The predictive value was stronger if LRTI was recurrent (n=50 (31%): OR 2.5, ΔX), required hospitalisation (n=38 (16%): OR 5.4, ΔR) or was associated with wheeze (n=87 (37%): OR 3.9, ΔX).Intra-breath FOT can identify healthy infants at risk of developing LRTI, wheezing or severe illness in the first year of life.

Objective: To assess the impact of HIV and antiretroviral exposure without infection on lung growth and function over the first 2 years of life. Design: Prospective observational study of an African birth cohort, Drakenstein Child Health Study. Method: Infants enrolled antenatally had lung function measured at 6 weeks, 1 and 2 years. HIV-infected women received antiretroviral therapy (ART) as per local guidelines. The association between HIV and antiretroviral exposure with lung function was assessed using mixed effects modelling. Results: Of 1143 infants born, two HIV-infected infants were excluded from analysis; 909 (80%) infants had lung function collected at 6 weeks [190 (21%) were HIV-exposed uninfected (HEU)]; 782 (69%) at 1 year and 741 (65%) at 2 years. At 6 weeks HEU infants had larger tidal volume compared with HIV-unexposed infants (1.13 ml, confidence interval: 0.02-2.23, P ¼ 0.045). High maternal viral load was associated with a 17% lower expiratory flow over 2 years (0.17, confidence interval 0.00-0.34, P ¼ 0.046). First-line ART initiated during pregnancy was associated with lower infant tidal volume at 6 weeks compared with those who initiated ART before pregnancy (À2.7 ml, À5.31 to À0.10, P ¼ 0.042), and low maternal CD4 þ cell counts associated with lower infant tidal over 2 years (À11.1 ml, À18.58-3.58, P ¼ 0.004). Conclusion: HIV exposure is associated with altered lung function in early life, with a vulnerable HEU subgroup based on maternal disease severity, immunological compromise and ART exposure. These data highlight the importance of ongoing surveillance of respiratory health in HEU children.

Objective: To assess whether increasing the daily intake of vitamin D will improve serum vitamin D levels and serve as primary prevention for respiratory morbidity in late premature infants.Methods: A randomized double-blinded clinical trial, including preterm infants born at 32 + 6 to 36 + 6 weeks' gestation, between May 2015 and January 2017. The control group received 400 IU of cholecalciferol daily compared to 800 IU daily in the intervention group. We measured the levels of 25 (OH) vitamin D at birth (cord blood), 6 months and 12 months, and followed the respiratory morbidity in both groups.Results: Fifty subjects were recruited during the study period: 25 subjects in each group. The median 25 (OH) vitamin D levels in the control group vs. the intervention group were: 26.5 vs. 34 nmol/L (p-value 0.271) at birth, 99 vs. 75.5 nmol/L (p-value 0.008) at 6 months and 72.5 vs. 75 nmol/L (p-value 0.95) at 12 months of age. Regarding respiratory morbidity, the intervention group, which had significantly lower vitamin D levels, had 3.5 vs. 1.9 (p-value 0.073) respiratory diseases during the follow-up year. Both groups had similar rates of Emergency department visits for respiratory symptoms and number of relievers consumed.Conclusion: Doubling the daily intake of vitamin D in the first year of life does not increase its serum levels when compared to the control group. We found a reversed association between serum vitamin D levels and the number of respiratory diseases in premature infants during the first year of life.Background: Primary immunodeficiency (PID) accompanied with recurrent respiratory infection is thought to have a devastating effect on pulmonary function. The major aim of this study was to investigate the relationships between chest computed tomography (CT) scan morphology of bronchiectasis, clinical severity of dyspnea, and deterioration of pulmonary function parameters.Methods: Children diagnosed with PID in a tertiary pediatric referred center in northern Taiwan were enrolled and retrospectively reviewed.Demographic and clinical data including age, sex, age at diagnosis of PID, follow-up period, chest CT images (modified Reiff scores), pulmonary function test (PFT) parameters, quality of life questionnaires (mMRC dyspnea scale) were collected and analyzed. Spearman's correlation was used for correlation between continuous variables. All statistical analyses were performed using SPSS software (version 20.0; NY, USA).Results: A total of 19 children with PID were enrolled. Among the latter, 13 patients were diagnosed as having bronchiectasis based on chest CT scans. Modified Reiff scores of chest CT scans were negatively correlated with FEV1 (% predicted) (Spearman r = -0.74, P = 0.009, n = 11) and FEV1/FVC ratio (Spearman r = -0.71, P = 0.014, n = 11). A significant negative correlation was found between the mMRC dyspnea scale and FEV1 (% predicted) (Spearman r = -0.69, P = 0.041, n = 9) and FVC (% predicted) (Spearman r = -0.78, P = 0.014, n = 9). In contrast, the mMRC dyspnea scale was positively co...