Serum ferritin as a predictive marker of pulmonary fibrosis in post-COVID-19

Pulmonary fibrosis is characterized by excessive matrix formation, which destroys typical lung architecture and increases the chances of comorbidity. It is essential to look into potential serum indicators for the early identification of individuals who may develop such severe fibrotic consequences since there is currently no specific marker for the early diagnosis of post-COVID-19 pulmonary fibrosis. The study is aimed at examining potential serum markers that could be used for early detection of pulmonary fibrosis in patients with COVID-19.

It is a cross-sectional retrospective observational study that included male (n = 26) and female (n = 10) patients who were confirmed positive for COVID-19 using the Reverse transcription polymerase chain reaction (RTPCR) test. Various hematological parameters, such as platelet count, white blood cell count (WBC count), platelet-to-lymphocyte ratio (PLR), white blood cell count to mean platelet volume ratio (WMR), red cell distribution width (RDW), plateletcrit (PCT), mean platelet volume (MPV), platelet distribution width (PDW), serum ferritin level, and CT severity scores (CT-SSs) were recorded. The association between hematological parameters, serum ferritin level, and CT-SS was assessed by the Pearson correlation test using the GraphPad Prism software (version 10). p < 0.05 was considered statistically significant.

The descriptive analysis revealed no significant correlation between platelet count (r = 0.1610, p = 0.3483), WBC count (r = -0.1381, p = 0.4217), PLR (r = 0.2262, p = 0.1847), WMR (r = -0.1093, p = 0.5258), RDW (r = 0.05982, p = 0.7289), PCT (r = -0.059, p = 0.752), MPV (r = 0.046, p = 0.788), and PDW (r = -0.06, p = 0.699) with CT-SS. However, a significant positive correlation was observed between CT-SS and serum ferritin levels in COVID-19 patients (r = 0.5452, p = 0.0006).

As there was a significant positive correlation between serum ferritin level and CT-SS, the serum ferritin level could be considered as a simple and cost-effective biomarker for predicting the development of lung fibrosis in long COVID-19 conditions after controlling the confounders.