Diffuse panbronchiolitis as parathymic syndrome in a Caucasian man previously treated for thymoma

Abstract

Diffuse panbronchiolitis (DPB) is a rare disease characterized by bronchiolitis and chronic sinusitis. Being largely restricted to East Asia, its actual incidence in Caucasian patients is probably underestimated. DPB has been described in association with thymic neoplasms, mainly arising as a consequence of immune dysregulation. We present a rare case of DPB diagnosed in a 69-year-old Caucasian man who had undergone surgery for stage 2A thymoma a year before. The patient came to our hospital complaining of exertional dyspnea and productive cough, with a persistent lung consolidation described at chest X-rays. High resolution computed tomography (CT) showed diffuse centrilobular micronodules and solid nodules, tree-in-bud opacities, peripheral consolidations and cylindrical bronchiectasis. Sinus disease was also demonstrated by CT. Analysis of bronchoalveolar lavage showed marked granulocyte inflammation and allowed the isolation of Haemophilus Influenzae. Consequently, the diagnosis of DPB was reached by integrating clinical, and radiological data. Long-term therapy with azithromycin was prescribed, and was found to be effective in controlling symptoms and reducing radiological abnormalities at 6-month clinical and CT follow-up. Confidence with the radiological presentation and clinical significance of DPB is necessary, since the condition is responsive and reversible to long-term macrolide treatment, the effect of which is mainly attributed to an anti-inflammatory, and immunoregulatory action.

Keywords: CT; Diffuse panbronchiolitis; Sinusitis; Thymoma.

Fig. 1

Chest high resolution computed tomography (HRCT) demonstrating multiple centrilobular nodules and micronodules through both lung bases (A-B), with a peripheral consolidation in the middle lobe (arrow in B). A cylindrical bronchiectasis is evident in the middle lobe (arrow in C, sagittal plane reformatted image).

Fig. 2

Unenhanced computed tomography of the paranasal sinuses showing sinus disease in the ethmoid, maxillary, and sphenoid sinuses (axial and coronal plane in A and B, respectively).

Fig. 3

HRCT at 6-month follow-up demonstrating a substantial reduction in the extent of lung abnormalities previously seen at the level of lung bases (A) and the resolution of bronchiectasis (B).