Typical and atypical pattern of pulmonary sarcoidosis at high-resolution CT: relation to clinical evolution and therapeutic procedures

Abstract

This study was done to evaluate the importance of high-resolution CT (HRCT) in defining pattern and extent of disease and establishing the clinical and therapeutic pathway in sarcoidosis. A retrospective analysis of 56 patients with pulmonary involvement of sarcoidosis was performed. Two groups were identified: 39 patients exhibiting a typical HRCT pattern and 17 patients with an atypical pattern. Inclusion criteria were the presence of radiological documentation (HRCT) of disease, clinical and radiological follow-up of 1 year and the beginning of any therapy within 1 month from the diagnosis. Among subjects not receiving therapy, the comparison between the two groups showed that the radiological findings remained stable in subjects with a typical pattern, while they worsened in more than 70% of cases with atypical appearance. Therapy was more effective in patients with a typical pattern. Recurrences occurred in both groups, but more often in patients with a typical pattern. One patient not receiving treatment experienced clinical worsening. Re-evaluation of HRCT within 1 year revealed no correlation between clinical deterioration and radiological changes. The findings of this study suggest that persistence of the inflammatory process rather than the radiological pattern at onset is a prognostic factor for recurrence.