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

Aim 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. Materials and methods 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. Results 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. Conclusions 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.