Rare Disease – Kartagener Syndrome

At Parkland morning report, Dr. Vadia discussed a rare case of Kartagener Syndrome.

Kartagener syndrome is a subset of primary ciliary dyskinesia with an autosomal recessive inheritance pattern, incomplete penetrance, and extensive heterogeneity. This disease is characterized by abnormal ciliary structure/function, leading to impaired mucociliary clearance (1).  It has has an incidence of 16,000-30,000 worldwide. The condition is most often associated with defects of the axoneme (the skeleton of cilia and flagella) due to defects in the genes that encode dyneins, kinesin, and microtubule-associated proteins (2).The defect ranges from dysmotility to complete immotility of cilia and flagella, resulting in a multisystem disease. Kartagener syndrome is characterized by the clinical triad of situs inversus viscerum, chronic sinusitis/nasal polyposis, and bronchiectasis. Though other features include a hearing loss, infertility in males (due to impaired motility of sperm), and possible infertility in females(3). They often present with symptoms similar to cystic fibrosis; if diagnosed in an adult, patients often recall a history of chronic productive cough which traced back to early childhood, chronic rhinitis often with nasal polyposis, chronic or recurrent maxillary sinusitis, and frequent ear infections(4). The differential includes cystic fibrosis, primary immunodeficiency syndromes, sequelae of HIV/AIDS, ABPA, and graft versus host disease in transplant patients(5).

Diagnosis can be made through imaging and histology. The CXR can reveal bronchiectasis and situs inversus, but can be non-specific; CT scan of the chest can be used to evaluate for infiltrates, bronchiectasis, etc.; evaluation of the sinuses will often reveal opacification of maxillary, ethmoid, and frontal sinuses. Mucosal biopsy from from ciliated epithelium can reveal dysfunctional cilia. Evaluation also includes microscopic semen analysis to evaluate sperm motility and structure. The saccharine test (a saccharin pellet is placed on the anterior end of the inferior turbinate and the time taken for the subject to notice the taste is recorded) can measure speed of transport into nasopharynx(4). Ciliary beat frequency can then be assessed by light microscopy and photometric techniques, and cilia fixed on electron microscopy(6). Further testing includes audiology and pulmonary function studies (4).

KartagenerThere is no curative treatment for this genetic disorder, so management is aimed at infection and symptom control. Thus, patients are often given prophylactic antibiotics (i.e. azithromycin), mucolytics, bronchodilators, inhaled corticosteroids, and pulmonary toilet. Lung transplantation is also an option (7).