Pulmonary Follow-Up Imaging in Cartilage-Hair Hypoplasia: a Prospective Cohort Study

Abstract

Cartilage-hair hypoplasia is a syndromic immunodeficiency with short stature, chondrodysplasia, and variable degree of immune dysfunction. Patients with cartilage-hair hypoplasia are prone to recurrent respiratory tract infections, and the prevalence of bronchiectasis ranges from 29 to 52%. Pulmonary complications contribute significantly to the mortality; therefore, regular lung imaging is essential. However, the optimal schedule for repeated lung imaging remains unestablished. We determined the rate and correlates of progression of structural lung changes in a prospectively followed cohort of 16 patients with cartilage-hair hypoplasia. We analyzed clinical, laboratory, and pulmonary functional testing data and performed lung magnetic resonance imaging at a median interval of 6.8 years since previous imaging. Imaging findings remained identical or improved due to disappearance of inflammatory changes in all evaluated patients. Patients with subtle signs of bronchiectasis on imaging tended to have low immunoglobulin M levels, as well as suffered from pneumonia during the follow-up. In conclusion, our results suggest slow if any development of bronchiectasis in selected subjects with cartilage-hair hypoplasia.

Keywords: CHH; MRI; RMRP; combined immunodeficiency; lung imaging; pulmonary complications.

Fig. 1

Pulmonary imaging of two study participants. Upper row: patient 6 with stable bronchiectasis (thick arrows) of the lower lobes; a the recent MRI (axial 3DFFE sequence) and 6 years earlier obtained, b baseline MRI (axial 3DFFE sequence), and c HRCT. Lower row: patient 2 with apical pleural thickening, parenchymal stranding and scarring (thin arrows), but no bronchiectasis. No progression of findings from baseline in HRCT or MRI imaging; d the recent MRI (axial T2 TSE sequence) and 6 years earlier obtained, e baseline MRI, and f HRCT