Diffuse Panbronchiolitis:
View cases of diffuse panbronchiolitis
Clinical:
Panbronchiolitis is a chronic inflammatory disease/cellular
bronchitis of unknown etiology that is seen
almost exclusively in Asians, predominantly Japanese individuals
[6]. It typically affects middle-aged men [5]. The disorder is not
necessarily associated with smoking [2]. Histologically, there is
thickening and mononuclear inflammatory infiltration of the walls
of the respiratory bronchioles.
Symptoms include chronic cough, progressive exertional dyspnea, wheezing, and recurrent/chronic sinusitis (30% of patients) and airway infection. Advanced disease is associated with chronic Pseudomonas aeruginosa infection. Death is usually secondary to respiratory failure or P. aeruginosa pneumonia. Between 60-70% of affected patients will be HLA-Bw54 positive [5]. Initial treatment with erythromycin is beneficial with a response in about 85% of patients, but the long term prognosis remains poor [3]. Lung transplant has been used in selected cases, but the disorder can recur in the transplanted lung [4].
X-ray:
CXR: CXR will demonstrate the presence of small nodular opacities up to 2 mm in size.
Computed tomography: On HRCT small, ill-defined centrilobular nodules are identified in 25% of cases and represent chronic inflammation and fibrosis in and around the respiratory bronchioles and the adjacent alveolar ducts. In patients with more severe disease, dilatation of bronchioles, intralumenal secretions, and bronchiolar wall thickening are present and appear as branching linear opacities (tree-in-bud pattern). Areas of decreased attenuation (producing mosaic attenuation) in the lung periphery may be identified and reflect air trapping. Bronchiectasis can also be seen.
REFERENCES:
(1) J Thorac Imaging 1995;10 (4):236-254 (p.252)
(2) Radiol Clin North Am 1998; Stulbarg MS, et al. Obstructive pulmonary disease: The clinician's perspective. 36 (1): 1-13
(3) Radiol Clin North Am 1998; Worthy SA, et al. Small airway diseases. 36 (1): 163-173
(4) Radiology2001; Collins J, et al. Frequency and CT findings of recurrent disease after lung transplantation. 219: 503-509
(5) AJR 2005; Pipavath SJ, et al. Radiologic and pathologic
features of bronchiolitis. 185: 354-363
(6) Radiographics 2017; Winningham PJ, et al. Bronchiolitis: a
practical approach for the general radiologist. 37: 777-794
