Primary ciliary dyskinesia with complex abnormalities including cleavage of B‐subfibers

Abstract

A 25‐year‐old Japanese woman suffered from repeated respiratory tract infections. Because of her characteristic medical history and imaging findings, we suspected primary ciliary dyskinesia (PCD) and performed a transbronchial biopsy. The biopsy revealed complex abnormalities of the ciliary structure including cleavage of the B‐subfibers observed by transmission electron microscopy analysis and the complete loss of ciliary motion by video analysis. Genetic examinations to diagnose PCD have progressed in recent years. However, in this case, the well‐known genetic mutations in causal genes of PCD were not detected via whole‐exome sequencing of the blood. Cleavage of the B‐subfibers in patients with PCD has never been reported. This case appears to be the first report of this PCD subtype in humans.

Analysis of the clinical features of Japanese patients with primary ciliary dyskinesia

“…The mean Lund-Mackay score was 12.8 (range, 7-17) points, which is comparable to the score of 10.6 (range, [6][7][8][9][10][11][12][13][14][15][16] reported in a PCD cohort [26] and to those reported in children with cystic fibrosis (17.3 for patients undergoing surgery and 11.5 for those treated medically) [27] . It has been reported that the Lund-Mackay score is not a predictor for endoscopic sinus surgery or hospitalization in PCD patients [28] .…”

“…The PICADAR score is calculated on the premise that there is wet cough, and the following seven clinical items are scored to predict the possibility of PCD: (1) full-term birth, (2) neonatal respiratory symptoms, (3) neonatal intensive care unit (NICU) admission, (4) misalignment of organs including situs inversus, (5) congenital heart disease, (6) persistent rhinitis, and (7) otitis media effusion, deafness, or perforated eardrum. Two points are assigned to (1), (2), (3), and (5), 4 points to (4), and 1 point to (6) and (7). The PICADAR score could be evaluated in 36 cases and ranged from 3 to 14 (mean, 7.3) points ( Fig.…”

“…The diagnosis of PCD requires the presence of characteristic clinical features such as chronic rhinosinusitis, otitis media with effusion, and bronchiectasis. The paucity of reports on PCD in Japan [5][6][7][8] may be due to low awareness of the disease among Japanese physicians; thus, it is probable that PCD is underdiagnosed in Japan.…”