Clinical and molecular characteristics of primary ciliary dyskinesia: A tertiary care centre experience

Mohammed Alzaid; Khalid Al-Mobaireek; Mohammed Almannai; Gawahir Mukhtar; Safa Eltahir; Adnan Zafar; Abdulali P Zada; Wadha Alotaibi

doi:10.1016/j.ijpam.2021.03.002

Clinical and molecular characteristics of primary ciliary dyskinesia: A tertiary care centre experience

Int J Pediatr Adolesc Med. 2021 Dec;8(4):258-263. doi: 10.1016/j.ijpam.2021.03.002. Epub 2021 Mar 11.

Authors

Mohammed Alzaid¹, Khalid Al-Mobaireek², Mohammed Almannai³, Gawahir Mukhtar¹, Safa Eltahir¹, Adnan Zafar¹, Abdulali P Zada⁴, Wadha Alotaibi⁴

Affiliations

¹ Pulmonary Division of the Pediatric Department, Children Specialized Hospital, King Fahad Medical City, Saudi Arabia.
² Pulmonary Division of the Pediatric Department, King Khalid University Hospital, Saudi Arabia.
³ Genetic and Metabolic Division of the Pediatric Department, Children Specialized Hospital, King Fahad Medical City, Saudi Arabia.
⁴ Pathology Department, Kind Fahad Medical City, Saudi Arabia.

Abstract

Background: Primary ciliary dyskinesia (PCD) is a ciliopathy with diverse clinical and genetic findings caused by abnormal motile cilia structure and function. In this study, we describe the clinical characteristics of confirmed PCD cases in our population and report the radiological, genetic, and laboratory findings.

Methods: This was a retrospective, observational, single-centre study. We enrolled 18 patients who were diagnosed with confirmed PCD between 2015 and 2019. We then analyzed their data, including clinical findings and workup.

Results: In our cohort, 56% of patients had molecularly confirmed PCD, and RSPH9 was the most common gene identified. Transmission electron microscopy (TEM) showed an ultrastructural defect in 64% of samples, all of which matched the genetic background of the patient. Situs inversus (SI) was observed in 50% of patients, and congenital heart disease was observed in 33%. The median body mass index (BMI) was 15.87 kg/m², with a median z score of -1.48. The median FEV1 value was 67.6% (z score - 2.43). Radiologically, bronchiectasis was noted in 81% of patients at a variable degree of severity. Lung bases were involved in 91% of patients. We were unable to correlate the genotype-phenotype findings.

Conclusion: We describe the clinical and molecular characteristics of patients with confirmed PCD in a tertiary centre in Saudi Arabia and report 9 new pathogenic or likely pathogenic variants in one of the PCD-associated genes.

Keywords: BMI, body mass index; Bronchiectasis; Electron microscopy; Genetic testing; HSVA, high-speed video microscopy analysis; IDA, inner dynein arm; NGS, next-generation sequencing; ODA, outer dynein arm; PCD, Primary ciliary dyskinesia; Primary ciliary dyskinesia; Situs inversus; TEM, Transmission electron microscopy; WES, whole-exome sequencing; nNO, nasal nitric oxide.