Clinical and Genetic Spectrum of Children with Primary Ciliary Dyskinesia in southwestern China: a single-center retrospective analysis

Background In southwestern China, a region characterized by the highest diversity of ethnic groups in the country, there is a notable paucity of research findings and case reports regarding primary ciliary dyskinesia (PCD). This study seeks to describe the clinical and genetic features of PCD patients in this specific geographic area, with the objective of enhancing awareness and understanding of the disease among healthcare professionals. Methods The demographic data, clinical features, laboratory and imaging findings obtained for 38 patients with PCD were retrospectively reviewed at a single center in southwestern China from January 2019 to November 2025, Whole exome sequencing was conducted to identify the genotype. Results The male-to-female ratio among children diagnosed with PCD was 0.8:1, the median age at diagnosis was 5 years (range: 2 months to 16 years). Of 38 patients, 89% (34/38) experienced recurrent wet cough; 66% (25/38) had sinusitis, 18% (7/38) had otitis media, 11% (4/38) had neonatal respiratory distress, 26% (10/38) had coexistent asthma. Chest computed tomography revealed that 21% (8/38) had varying degrees of bronchiectasis. The most common pathogen in the airway was Streptococcus pneumoniae (7/28, 25%). Genes with the highest incidence of mutations were HYDIN (6/26), followed by DNAH11 (3/26), DNAH5 (3/26), CCNO (3/26) and DNAH7 (3/26). Four genes (DNAH9, CCDC40, CFAP74 and DNAI2) were each mutated once. Among the six patients with HYDIN gene mutations, three clinical features (Bronchomalacia, diffuse bronchiolitis and hydrocephalus) were observed that had not been previously reported in HYDIN-PCD patients. Conclusions In southwestern China, results describing the clinical and genetic spectrum of PCD do not completely agree with findings of previous reports, which may be associated with specific ethnic and regional factors. The clinical findings of some special cases expand our understanding of potential atypical phenotypes associated with PCD, while also offering valuable clinical experience for the diagnosis of similar cases.