Definition


Rare autosomal recessive disorder characterized by absent or dysmotile cilia caused by a defect in the dynein arm of microtubules.

Etiology


Pathophysiology


Pasted image 20250409095013.png Dynein: a class of motor proteins that convert cellular energy to mechanical energy. They allow for migration, propagation, and movement of cells/organelles usually along the microtubules.

Clinical features


  • Chronic productive cough
  • Recurrent otitis, sinusitis, and nasal polyps
  • Bronchiectasis
  • Conductive hearing loss
  • Displaced heart sounds (as a result of dextrocardia)
  • Infertility in men due to decreased sperm motility as a result of defective flagella
  • Reduced fertility in women (and rarely ectopic pregnancy) due to defective cilia in fallopian tubes
  • Kartagener syndrome: classic triad of situs inversus, recurrent sinusitis, and bronchiectasis

Mnemonic

You can memorize the cause of Kartagener syndrome by thinking of Kartagener’s restaurant that only has ‘take-out’ service because there is no dine-in (dynein).


Diagnostics

  • Nasal nitric oxide test: reduced nasal nitric oxide (screening test)
    • Ciliary beating is thought to play a role in stimulating nitric oxide synthase (NOS), the enzyme responsible for NO production
  • Genetic tests for dynein arm mutations
  • Chest x-ray: bronchiectasis, dextrocardia, and situs inversus (suggests Kartagener syndrome)

Pasted image 20240506213541.png

Tip

Same pulmonary symptoms and infertility like cystic fibrosis


Treatment