Primary ciliary dyskinesia (PCD) is an autosomal recessive disorder characterized by the presence of purulent rhinorrhea and bronchorrhea starting at birth or during the first months of life, relapsing infections of the upper and lower airways, median otitis, and infertility. In 40-50% of cases, it is associated with situs inversus.
Its prevalence is approximately 1:10,000-20,000 individuals. It is secondary to abnormal structure and function of cilia in the epithelium of the respiratory and reproductive tracts, leading to defective mucociliary clearance with obstruction due to abnormally thick secretions, thus promoting bacterial colonization and superinfection. It has occasionally been described to follow X-linked or autosomal dominant inheritance patterns. In recent years, mutations in more than 30 different genes have been reported as causative of 70% of PCD cases, revolutionizing the diagnosis of the disease.