FOT measurements were feasible in Emirati school-children. New FOT reference equation in Emirati children were derived. FOT reference equation in Emirati children was different from published equations in Caucasians.

Respiratory diseases, especially asthma, are common in children. While spirometry contributes to asthma diagnosis and management in older children, it has a limited role in younger children whom are often unable to perform forced expiratory manoeuvre. The development of novel diagnostic methods which require minimal effort, such as forced oscillation technique (FOT) is, therefore, a welcome and promising addition. FOT involves applying external, small amplitude oscillations to the respiratory system during tidal breathing. Therefore, it requires minimal effort and cooperation. The FOT has the potential to facilitate asthma diagnosis and management in pre-school children by faciliting the objective measurement of baseline lung function and airway reactivity in children unable to successfully perform spirometry. Traditionally the use of FOT was limited to specialised centres. However, the availability of commercial equipment resulted in its use both in research and in clinical practice. In this article, we review the available literature on the use of FOT in childhood asthma. The technical aspects of FOT are described followed by a discussion of its practical aspects in the clinical field including the measurement of baseline lung function and associated reference ranges, bronchodilator responsiveness and bronchial hyper-responsiveness. We also highlight the difficulties and limitations that might be encountered and future research directions.

The standard Arabic version of the Childhood Asthma Control Test (C-ACT) has never been previously evaluated in Arab countries. We studied its correlation in Arabic speaking children in the United Arab Emirates (UAE), with both the GINA assessment of asthma control and the resulting changes in asthma management. The Arabic C-ACT was completed by the children or by their parents when needed. A GINA based level of asthma control score was assigned by their managing physician. The correlation between the different cut- scores of the C-ACT and GINA were studied. A total of 105 eligible children with asthma (aged between 4 and 11.8 years, 61% boys) were enrolled. The Arabic translated C-ACT had a high reliability (Cronbach alpha 81%) and validity (as it correlated well with the GINA level of control). We found that using it with the traditional cut-score of 19 overestimated the degree of asthma control. Instead, a calculated optimal cut-score of 20 estimated more accurately the level of asthma control as assessed both by the GINA assessment and also by changes in asthma management. The current Arabic version of the C-ACT has a good reliability and validity. By using a single optimal cut-point of 20, it can be used to assess both the level of asthma control and of treatment control. It does not, however, accurately define asthma control when using the originally proposed cut-score of 19. Physicians need to recognise that the C-ACT cut-points may vary in different populations. We suggest that cut-scores of translated versions need to be modified in different geographical settings.

Founder mutations and autosomal recessive (AR) disorders are common in the Arabian Peninsula due to frequent consanguineous marriages. As a result, the pulmonary service at Tawam Hospital (Al Ain, UAE) routinely requests genetic testing for children with persistent (unexplained) respiratory problems. The main purpose of this report was to underscore the usefulness of these tests. Ten children with severe respiratory diseases due to complex genetic findings are described here. Forty‐one variants (six novel) were detected, averaging four per patient (range: 1‐9). Seven (17%) variants were homozygous and 34 (83%) heterozygous; some variants were known to show monoallelic expression. Using binomial probability distribution, the fetal‐risk for having AR disorder(s) as a function of the number of shared variants by a couple ranged from 0.25 (having one shared variant) to 0.9249 (having nine shared variants). In cultures where increased size of homozygous genomic segments is common, children often have multiple variants that could cause complex clinical phenotypes. Identifying pathogenic variants assists in clinical care, family counseling, and disease prevention through genetic screening.

Genetic variants of small airways and interstitial pulmonary disease have not been comprehensively studied. This cluster of respiratory disorders usually manifests from early infancy (‘lung disease in utero’). In this study, 24 variants linked to these entities are described. The variants involved two genes associated with surfactant metabolism dysfunction (ABCA3 and CSF2RB), two with pulmonary fibrosis (MUC5B and SFTP), one with bronchiectasis (SCNN1B), and one with alpha-1-antitrypsin deficiency (SERPINA1). A nonsense variant, MUC5B:c.16861G > T, p.Glu5621*, was found in homozygous state in two siblings with severe respiratory disease from birth. One of the siblings also had heterozygous SFTPA1:c.675C > G, p.Asn225Lys, which resulted in a more severe respiratory disease. The sibling with only the homozygous MUC5B variant had lung biopsy, which showed alveolar simplification, interstitial fibrosis, intra-alveolar lipid-laden macrophages, and foci of foreign body giant cell reaction in distal airspaces. Two missense variants, MUC5B:c.14936 T > C, p.Ile4979Thr (rs201287218) and MUC5B:c.16738G > A, p.Gly5580Arg (rs776709402), were also found in compound heterozygous state in two siblings with severe respiratory disease from birth. Overall, the results emphasize the need for genetic studies for patients with complex respiratory problems. Identifying pathogenic variants, such as those presented here, assists in effective family counseling aimed at genetic prevention. In addition, results of genetic studies improve the clinical care and provide opportunities for participating in clinical trials, such as those involving molecularly-targeted therapies.