Red cell distribution width (RDW) as a biomarker of disease severity in ILD patients

Abstract

Introduction: The course of interstitial lung disease (ILD) is characterized by variable disease progression pattern associated with high morbidity as well as mortality. The red cell distribution width (RDW) is a readily available laboratory parameter reported with complete blood count(CBC) that may provide important prognostic information in patients with ILD. Methods: In this retrospective study,RDW values, demographics and CT scan data from 24 patients with ILD was analyzed. We compared RDW value with dyspnea score and CT score to test the usefulness of this parameter in patients with ILD.A simple CT scoring method was used in which the lungs were divided into three zones and a score of 0 was given if no abnormality was found in a zone, a score of 1 for any abnormality except for honeycombing (ground-glass, reticular markings, bronchiectasis) and a score of 2 if honeycombing was present. The total score was calculated by adding up these zonal scores. Higher CT score and higher dyspnea score represent greater severity of disease. Results: 24 patients with ILD were evaluated in whom baseline CBCs were available. Out of 24, 11 were males and 13 were females with mean age of 63.75+9.09 years. The range in the RDW was 12 to 27(normal 15 and CT score was higher in these patients. 7 patients had >20 out of which 6 had dyspnea score V. Patients with normal RDW values had a less CT score and dyspnea score as compared with those whose RDW was >15. Conclusions: RDW can be used as a biomarker to identify the severity of disease or pulmonary compromise in ILD patients.