Incidentally detected Kartagener's syndrome

Clinical History

A 13-year-old boy was referred for ultrasonography of the abdomen for abdominal pain. He didn't have any significant medical or surgical history.

Imaging Findings

Ultrasonography of the abdomen revealed situs inversus. The rest of the scan was normal. However, no cause for abdominal pain was found. Computed tomography of the abdomen and thorax confirmed situs inversus totalis along with features of bronchiectasis in bilateral lower lobes and left middle lobe. The normal pulmonary anatomy was reversed suggesting situs inversus thoracalis with the right lung having two lobes (bi-lobar) and the left lung having three lobes (tri-lobar). Centrilobular nodules with tree-in-bud pattern were noted in bilateral lower lobes, left upper and middle lobes. CT scan of paranasal sinuses revealed mucosal thickening of all sinuses. Semen analysis could not be done due to patient's age.

Discussion

Kartagener’s syndrome (KS) is a subset of primary ciliary dyskinesia (PCD) characterized by the clinical triad of situs inversus, sinusitis and bronchiectasis. This triad was first recognized as a distinct congenital syndrome in 1933 by Manes Kartagener, a Zurich pulmonologist. It is an autosomal recessive disorder. Incidence is about 1 in 30, 000 live births. It accounts for one-tenth of the cases of bronchiectasis and about one-sixth of the cases of situs inversus. About 50% of the people affected with PCD have Kartagener’s syndrome. Male patients with this syndrome have infertility because of immotile spermatozoa. Afzelius (1960) was the first to recognize the relationship between KS and male infertility and attribute it to defective ciliary ultrastructure [1, 2, 3, 4].

Ultrastructural defects (electron microscopy) in cilia include 1) complete or partial absence of dynein arms: inner arms, outer arms or both 2) radial spoke defect 3) microtubular transposition. This ultimately leads to impaired ciliary beating and mucociliary clearance [4, 5].

The clinical picture includes chronic sinusitis and chronic otitis media, bronchiectasis, infertility in both men and women, increased incidence of ectopic pregnancy in women. The most common respiratory pathogens are Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus aureus and Pseudomonas. At times patients with KS are diagnosed when they are evaluated for infertility [1, 3, 4].

Radiological features include those of situs inversus, bronchiectasis, sinusitis. Bronchiectactic changes are much milder than in cystic fibrosis [6]. In addition CT can demonstrate consolidation, mucocele (impacted mucus in bronchiole), tree-in-bud pattern or centrilobular nodules (due to endobronchial spread of infection), mosaic perfusion, scarring due to recurrent infection.

It is important to note that up to 20% of patients with situs inversus can have KS [7]. Since our patient had the triad of situs inversus, sinusitis and bronchiectasis, KS was diagnosed. A confirmation of the diagnosis of PCD relies on electron microscopic examination of nasal and bronchial cilia for ultrastructural defects and abnormal ciliary beating which couldn't be done in our case. Nasal nitric oxide measurement and saccharin test are rapid and reliable screening methods [3].

Treatment includes antibiotics, bronchodilators, mucolytics, and chest physiotherapy, influenza and pneumococcal immunisation. Surgical treatment includes placement of tympanostomy tubes, endoscopic sinus surgery, lobectomy and pneumonectomy for localised lung damage with recurrent haemoptysis [1, 3, 4].

Although there is no specific treatment, failure to diagnose this may lead to unnecessary repeated admissions, investigations and inappropriate treatment. Late diagnosis with established bronchiectasis worsens the overall prognosis, even with the best of treatment modalities. Hence an early diagnosis is warranted [1, 3].

Differential Diagnosis List

Final Diagnosis

Kartagener's syndrome

URL:	https://www.eurorad.org/case/13576
DOI:	10.1594/EURORAD/CASE.13576
ISSN:	1563-4086