Genotype and Ultrastructure Correlation in Primary Ciliary Dyskinesia Among Saudi Children: A Case Series.

Background

Primary ciliary dyskinesia (PCD) is a rare inherited disorder of motile cilia causing chronic oto-sinopulmonary disease. Transmission electron microscopy (TEM) remains essential for confirming ultrastructural defects, especially in resource-limited settings. This study characterizes the clinicopathologic and molecular spectrum of Saudi children with PCD.

Methods

Ten Saudi children with confirmed PCD (2018-2025) were retrospectively reviewed. Clinical, radiological, ultrastructural, and whole exome sequencing (WES) data were analyzed to assess genotype-phenotype correlation.

Results

The cohort included seven females and three males (median age 9 years). Consanguinity was present in 80%, and five had situs inversus. TEM showed class 1 defects in 3 patients, class 2 in 2, and abnormalities of uncertain significance in 3. WES identified variants in DNAAF3, DNAAF4, RSPH9, GAS2L2, and NME5.

Conclusions

This study expands the molecular and ultrastructural profile of PCD in Saudi Arabia. TEM remains essential for diagnosis and variant interpretation.