대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Broncholitis Obliterans in a Patient with SLE

Radiologic Findings

Transverse thin-section CT scans (collimation, 1 mm) obtained at full inspiration in a prone position show mosaic attenuation in the whole lung. Pulmonary vessels appears to be larger in number and size in high-attenuation areas than low-attenuation areas, suggesting that low-attenuation areas are abnormal. Thin-section CT scans (collimation,1 mm) obtained at full expiration in a prone position show low attenuation areas are persistent, suggesting the parenchymal low attenuation is due to airway abnormality, rather than vascular abnormality. The diagnosis was made clinically without biopsy.

Brief Review

Bronchiolitis obliterans (BO) or constrictive bronchiolitis is characterized by airflow limitation due to submucosal and peribronchiolar inflammation and fibrosis, primarily involving respiratory bronchioles in the absence of diffuse parenchymal inflammation. Pulmonary involvement is characteristically patchy and the diagnosis may be difficult to establish even following open lung biopsy. Several cases of bronchiolitis obliterans similar to that seen in rheumatoid disease have been described in patients with SLE(1,2). Affected patients have airflow obstruction on lung function testing and no parenchymal change on chest radiograph (2). In some patients, mild hyperinflation or subtle peripheral attenuation of the vascular marking may be seen (3). The most obvious HRCT findings are that of focal, often sharply defined, areas of decreased lung attenuation associated with vessels of decreased caliber. This change represents a combination of air trapping and oligemia, typically occurring in the absence of parenchymal consolidation (4). Bronchiectasis, mainly at a subsegmental level, may be noted. In addition, expiratory CT shows focal areas of air trapping consistent with small airway obstruction (2). Rarely, centrilobular branching opacities or ill-defined centrilobular opacities may be predominant finding. Ill-defined centrilobular opacities may suggest active, cellular stage of bronchiolar inflammation. Lung perfusion scan may help to differentiate the constrictive bronchiolitis from mosaic perfusion due to pulmonary vascular disease, such as vasculitis, thromboembolism.

References

1. Kinney WW, Angelillo VA. Bronchiolitis in systemic lupus erythematosus. Chest 1982;82:646-9.
2. Fraser RS, Muller NL, Colman N, Pare PD. Connective tissue disease. In: Fraser RS, Muller NL, Colman N, Pare PD, eds. Diagnosis of disease of the chest , 4th ed. Philadelphia : W.B. Saunders, 1999:1421-1487.
3. Breatnach E, Kerr I. The radiology of cryptogenic obliterative bronchiolitis. Clin Radiol 1982;33:657-661.
4. Garg K, Lynch DA, Newell JD, King TE Jr. Proliferative and constrictive bronchiolitis: classification and radiologic features. AJR 1994;162:803-8.

Keywords

Airway, Connective tissue diseases, Bronchiolitis, Broncholitis Obliterans in a Patient with SLE