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Background: Infant pulmonary function tests (iPFTs) in subjects with neuroendocrine cell hyperplasia of infancy (NEHI) have demonstrated substantial expiratory airflow obstruction and air trapping.Research Question: Can indices from iPFTs be used in the diagnosis of NEHI?Study Design and Methods: This is an observational case-control study evaluating iPFT results from a registry of patients assessed at the Hadassah Hebrew University Medical Center between 2008 and 2018. iPFTs results in infants with NEHI were compared to two disease control infant groups (infants evaluated for recurrent wheezing and infants evaluated due to prematurity) and a spirometry control group of infants with normal expiratory airflow, using the Kruskal-Wallis test. Receiver operating characteristic (ROC) curves were used to assess the diagnostic accuracy of iPFT indices.Results: We evaluated iPFT data in 481 infants (15, NEHI; 292, wheezing; 128, premature; and 46, spirometry control group). Infants with NEHI had significantly increased trapped air volumes (median functional residual capacity measured with infant whole-body plethysmography [FRCpleth] was 199% predicted; median ratio of residual volume to total lung capacity was 59% predicted) when compared with results in all evaluated groups of infants (P < .001), including multiple pairwise comparisons. Airflow limitation was demonstrated in infants with NEHI when compared with the infants in the spirometry control group but was similar to the two disease control groups. FRCpleth had the best discriminatory ability for NEHI diagnosis, with an FRCpleth ≥ 150% predicted demonstrating a ROC of 0.91 (95% CI, 0.82-1.00), sensitivity of 86.7% (95% CI, 59.5%-98.3%), and specificity of 95.5% (95% CI, 93.2%-97.3%).Interpretation: Findings on iPFTs of markedly increased air trapping, out of proportion to the degree of airflow limitation, are characteristic of infants with NEHI. iPFT results demonstrating an FRCpleth ≥ 150% predicted are highly specific for NEHI and may aid in early diagnosis. Further research is required to confirm these findings in a prospective cohort and to understand the pathophysiologic explanation for these findings. [ABSTRACT FROM AUTHOR]

Objective: To evaluate tidal breathing (TB) flow-volume and flow-time curves for identification of expiratory airway obstruction in infants. Methods: Pulmonary function tests were analyzed retrospectively in 156 infants aged 3-24 months with persistent or recurrent respiratory complaints. Parameters derived from TB curves were compared to maximal expiratory flow at functional residual capacity (maxFRC) measured by rapid thoracoabdominal compression technique. Analyzed parameters were: inspiratory time (tI), expiratory time (tE), tidal volume, peak tidal expiratory flow (PTEF), time to peak tidal expiratory flow (tPTEF), expiratory flow when 50% and 25% of tidal volume remains in the lungs (FEF50, FEF25, respectively), and the ratios tPTEF/tE, tI/tE, FEF50/PTEF, and FEF25/PTEF. Statistical comparisons between flow indices and TB parameters were performed using mean squared error and Pearson's sample correlation coefficient. The study population was also divided into two groups based on severity of expiratory obstruction (above or below z-score for maxFRC of −2) to generate receiver operating characteristic (ROC) curves and calculate discriminatory values between the groups. Results: TB parameters that were best correlated to maxFRC were: tPTEF/tE, FEF50/PTEF, and FEF25/PTEF, with r = 0.61, 0.67, 0.65, respectively (p < 0.0001 for all). ROC curves for FEF50/PTEF, FEF25/PTEF and tPTEF/tE showed areas under the curve of 0.813, 0.797, and 0.796, respectively. Cutoff value z-scores of −0.35, −0.34, and −0.43 for these three parameters, respectively, showed an 86% negative predictive value for severe airway obstructions. Conclusion: TB curves can assist in ruling out severe expiratory airway obstruction in infants. [ABSTRACT FROM AUTHOR]

A teenage girl was evaluated for recurrent right pneumonia. The evaluation revealed a calcified mediastinal mass that compressed the right intermediate and middle lobar bronchi, as well as the right pulmonary artery and veins. The clinical picture together with imaging studies and borderline positive serology testing suggested a diagnosis of fibrosing mediastinitis associated with histoplasmosis. This rare condition is characterized by the local proliferation of invasive fibrous tissue within the mediastinum due to a hyperimmune reaction to Histoplasma capsulatum. Antifungal and anti-inflammatory therapies are usually ineffective, and surgical intervention contains a high morbidity risk. Palliative surgery and stenting of the compressed airway have been suggested. In the past, the prognosis was thought to be poor, but recent studies demonstrate a more positive outcome. Our patient had been radiologically and functionally stable under follow-up for over thirteen years and has married and delivered two healthy children, both following an uneventful pregnancy. [ABSTRACT FROM AUTHOR]

Objective: Spirometry including bronchodilator responsiveness is considered routine in the workup of asthma in older children. However, in wheezy infants the existence of bronchodilator responsiveness and its prognostic significance remain unclear.Methods: Infants (< 2 years) with chronic or recurrent wheezing or coughing were evaluated by infant pulmonary function testing (PFT). Maximal expiratory flow at the point of functional residual capacity (V̇maxFRC) was measured before and 20 minutes after salbutamol administration. Only infants with an obstructive profile (V̇maxFRC < 80% predicted) were included. The infants were divided into two groups with regard to whether or not a response to salbutamol was observed on PFT. A response was defined as a mean V̇maxFRC after salbutamol administration exceeding the upper confidence interval limit of individual pre-bronchodilator V̇maxFRC measurements. Follow-up data was gathered after a mean of 2 years.Measurements and Main Results: Sixty infants were included in the study of which 32 (53%) demonstrated responsiveness to bronchodilators. The infants in the responsive group had a significantly higher frequency of physician visits for wheezing than the non-responders (3.0 mean visits/yr vs. 1.5 respectively,P= 0.03), and had a higher likelihood of having received asthma medication in the last year of the follow-up period (84% vs. 50% respectively, RR: 1.68[1.10–2.56]). At the end of the follow-up period, more parents in the responsive group reported continued respiratory disease (71% vs. 22%, RR:3.21[1.30–7.95]).Conclusions: Bronchodilator responsiveness can be demonstrated by infant PFT in infants with recurrent wheezing and can predict increased respiratory morbidity until 3 years of age. [ABSTRACT FROM PUBLISHER]