Comparative study of the serum hepcidin level of patients with pneumonia in COVID-19 and Pneumocystis pneumonia.

In the context of a pandemic caused by the SARS-CoV-2 virus, for a patient with respiratory symptoms and bilateral lung damage, COVID-19 becomes the first disease in the differential diagnostic search. Pneumonia in COVID-19 shares many characteristics with Pneumocystis pneumonia. One of the possible markers of the severe course of COVID-19 is hepcidin, a peptide hormone that negatively regulates iron metabolism. There are no data on the value of hepcidin in Pneumocystis pneumonia in the published scientific literature. The purpose of this study is to conduct a comparative analysis of hepcidin in the blood serum of patients with pneumonia in COVID-19 and Pneumocystis pneumonia to clarify their pathogenetic features. A case-control observational study was conducted, including 68 patients with pneumonia in COVID-19 and 44 patients with HIV infection and Pneumocystis pneumonia (PCP/HIV). Determination of hepcidin was carried out by ELISA using the ELISA Kit for Hepcidin. Statistical data processing was carried out using the MedCalc 19.2.6 software. Results. Comparative analysis of serum hepcidin levels in the study groups showed that hepcidin is statistically significantly higher in PCP/HIV than in COVID-19 - the median value is 22 times higher (p <0.0001). When examining the ROC curve for hepcidin, it was found that this biomarker has a high diagnostic potential and indicates a higher probability of COVID-19 than PCP/HIV at values ≤768.044 pg / ml. In the context of the COVID-19 pandemic, it is necessary to remember about other diseases that manifest themselves with a similar clinical and radiological picture. COVID-19 and PCP/HIV share many similarities; the peptide hormone hepcidin has shown itself as a potential differential diagnostic marker between them, and therefore the need for further studies of hepcidin is justified, taking into account the severity of the course of COVID-19, the presence of comorbidities and in a comparative aspect with pathologies that «mimic» under COVID-19.