INTRODUCTION: Primary ciliary dyskinesia (PCD) is characterized by sino-pulmonary disease and caused by abnormal ciliary structure and function. It is autosomal recessive, genetically heterogeneous with a prevalence of 1/12-17,000 (1). We report a case of PCD with a radiographic presentation of anterior mediastinal and left upper quadrant masses.
CASE PRESENTATION: A 41-yr-old gentleman presented with a recent diagnosis of bronchiectasis. He had recurrent pulmonary infections since childhood and recently expectorated 40mls of sputum daily. He had neonatal respiratory compromise (1), recurrent otitis media requiring grommet placements since childhood, and recurrent sinusitis requiring surgery at age 38. He had no children despite unprotected intercourse. He recently underwent a left-sided appendectomy with laparotomy findings of a left sided cecum and absence of colon in the left paracolic gutter. He was in excellent physical shape related to frequent aerobic and weight training exercise.Physical exam revealed a well nourished physically fit 90kg male with bilateral tympanic scarring with persistent grommet in the left ear. His naso-pharynx appeared moist and red. Pulmonary auscultation revealed bibasal crackles without wheeze.Spirometry identified normal FEV1 (102% predicted), FVC (96%) and FEF25-75% (140%) . Sputum culture identified smooth Pseudomonas aeruginosa. Chest x-ray revealed bilateral lower lobe bronchiectasis with a smooth large anterior mediastinal mass (Figure 1 (a)) and displacement of the stomach medially with soft tissue fullness in the left upper quadrant (Figure 1 (s)). Contrast-enhanced CT with high resolution slices confirmed right middle and bilateral lower lobe mild central bronchiectasis. Dilated ascending aorta and bilateral superior vena cavas accounted for the anterior mediastinal mass on chest x-ray. Multiple left upper quadrant splenules accounted for the left upper quadrant mass (Figure 2 (s)). Inferior vena cava interruption with hemiazygous continuation was also identified.The diagnosis of PCD was confirmed by low nasal nitric oxide (48 nl/min, normal= 376+/-124 nl/min (1)) and nasal ciliary biopsy and electron microscopy of ciliary ultrastructure revealing absent outer dynein arms. Genotype DNAI1 mutations was negative (1).
DISCUSSIONS: Although this patient was diagnosed late with PCD, he displayed many classic features including neonatal respiratory compromise, otitis media, sino-pulmonary disease, bibasal bronchiectasis and infertility (1). His preserved pulmonary function was in part related to airway clearance associated with frequent exercise. Estimates suggest approximately 20,000 cases of PCD in the USA, and many are undiagnosed. Situs inversus totalis (SI) occurs in ∼50% of PCD patients (Kartagener's syndrome) which helps with accurate diagnosis (1). There are a few prior reports of PCD with situs ambiguus (heterotaxy), organ laterality defects other than situs inversus totalis. There are a number of subtypes of situs ambiguus including abdominal situs inversus (visceral heterotaxy), isolated dextrocardia and left (polysplenia syndrome) and right (asplenia syndrome) disorders of isomerism sequence.Features of the polysplenia syndrome include multiple splenules, bilateral bilobed lungs, and duplicate superior vena cavas (2). A debilitating association is congenital heart disease (90-100%); however the severity of phenotype varies (2).To determine the incidence of situs ambiguus and associated anatomic anomalies in a population of PCD patients, we investigated 326 well-characterized PCD patients from four international centers and identified an incidence of 6% (unpublished data). 50% of these patients displayed features of the polysplenia syndrome.
CONCLUSION: A case of PCD with features of the polysplenia is presented. Screening for PCD should be considered in patients with anatomical features of heterotaxy with concomitant sinopulmonary disease.
DISCLOSURE: Marcus Kennedy, None.