Maldevelopment of intrapulmonary bronchial cartilage in congenital diaphragmatic hernia

Abstract

Background Pulmonary hypoplasia is an important cause of morbidity and mortality in infants with congenital diaphragmatic hernia (CDH). This study aimed to verify our hypothesis that the abnormal development of bronchial cartilage as well as alveolar immaturity, might play a central role in hypoplasia of the lung in human CDH. Method We retrospectively analyzed autopsied lungs from 10 CDH cases and compared with nine age‐matched controls to assess the bronchial cartilage and alveolar maturity using morphological techniques. Result Ki‐67 and thyroid transcription factor‐1 (TTF‐1) expression in the alveoli significantly increased in bilateral lungs with CDH. The shortest distance from the bronchial cartilage to the pleura was significantly shorter in ipsilateral (left) lungs with CDH, showing a positive correlation with the radial alveolar count (RAC). Regarding the small bronchial cartilages less than 20 000 μm2, the average cartilage area significantly decreased in left lungs with CDH, and tended to decrease in right lungs with CDH. In addition, cartilage around the bronchi less than 200 μm in diameter tended to be smaller in left lungs with CDH. In contrast, regarding the cartilage around the bronchi 200 to 400 μm in diameter, the ratio of the total cartilage area relative to the bronchial diameter tended to be higher in left lungs with CDH, although there was a large variation. Conclusions These opposite directional cartilage abnormalities around the distal and more proximal bronchi support our hypothesis that abnormal development of bronchial cartilage might play an important role in the hypoplastic lung in CDH.

Pediatric pulmonology 2020 year in review: Rare and diffuse lung disease

“…Tando et al 44 Esophageal atresia (EA), a congenital foregut anomaly, affects about 1 in 3000 live births and is associated with significant respiratory morbidity. 46 Donoso et al 47 reported on 47 patients with a history of EA who performed lung function testing at either 8 or 15 years of age in a single-center follow-up study.…”

“…Two papers sought to clarify aspects of CDH pathogenesis. Tando et al 44 examined autopsied lungs from ten children with CDH, compared to nine age‐matched controls. They observed several abnormalities of bronchial cartilage in the CDH lungs, suggesting that abnormal development of bronchial cartilage may play a role in pulmonary hypoplasia associated with CDH.…”