Morphological changes of nasal and duodenal mucosa in patients with cystic fibrosis

Abstract

Cystic fibrosis (CF) is an inherited multisystemic disorder that results in generalized dysfunction of exocrine glands. In patients with cystic fibrosis dyscrinia with affection of exocrine glands function is a main problem of the upper and lower respiratory tract. In addition to chronic obstructive pulmonary disease, chronic sinusitis, nasal polyposis and hypertrophy of inferior turbinates with nasal airway obstruction are typical signs. To understand pathophysiological mechanisms in CF and to correlate morphological findings with clinical symptoms, investigations of nasal mucosa are important. Tissue samples of inferior turbinates were taken during nasal surgery from 7 children, ranging from 3 to 11 years of age between September 1998 and May 2000. Histological sections were cut followed by a light- and electron microscopical examination (EM 902 A Zeiss). Additionally, specimens of duodenal mucosa were investigated. In comparison with sections of normal nasal mucosa the lamina propria mucosae shows different morphological changes. Under a thick layer of respiratory epithelium with a high portion of goblet cells and particulary vacuoles there is an edematous subepithelial area. The capillary layer is reduced and the seromucous glands show an atypical morphological structure with widely mucous cells and cystic dilatation. On an ultrastructural level the glandular cells show atypical and inhomogeneous glandular droplets in the supranuclear cell portion. A viscous secretion was detectable at the glandular lumen. The nucleus contains dispersed chromatin as a sign of increased activity and the structures of Golgi apparatus were obviously detectable. In respective literature studies on the different morphological changes on light- and electron microscopical level in CF-associated rhinopathies are rare. This histological study demonstrated various morphological changes of nasal mucosa and shows a correlation between the glandular dysfunction and the typical symptoms in CF. Additionally a comparison with ultrastructural findings of CF-enteropathies is proposed. These findings could help to look at new aspects in the pathophysiology for patients with CF.