Prognostic value of red cell distribution width in patients with sarcoidosis

Abstract

Sarcoidosis is a multisystem granulomatous disorder of unknown etiology. There are no data on the indications for specific tests or optimal frequency for monitoring of the disease activity in sarcoidosis. Complete blood counts, demographics and pulmonary function data from sarcoidosis patients evaluated between 2006 and 2012 were collated retrospectively. During follow-up, the latest red cell distribution width (RDW) values of the patients were recorded. The prognosis and diagnosis of sarcoidosis was based on according to the guideline. Sarcoidosis progression was classified as follows: remission, stable disease and progreesive disease. The diagnosis was based on histopathological findings in 93 out of 138 (67.4%) patients. In our cohort, the baseline mean RDW levels were 14.1% ± 1.2. The RDW distribution by stage was as follows: stage I: 14.0% (± 1.6), II: 14.2% (± 1.5), III: 13.8% (± 0.9) and IV: 15.8% (± 2.0). In patients with stage IV, baseline and follow-up values of RDW were found to be significantly higher than the other stages. While the mean baseline RDW was 14.8 (± 1.4) in the progressive disease, upon follow-up, the mean RDW had increased to 16.5% (± 1.4) (P = 0.021), No difference was found between the baseline and follow-up levels of RDW in the regressive and stable groups. Serial RDW levels may be beneficial marker to predict progression of sarcoidosis.