High levels of mid-regional proadrenomedullin in ARDS COVID-19 patients: the experience of a single, Italian Center

OBJECTIVE: This study evaluated the ability of mid-regional proadrenomedullin (MR-proADM) to identify disease severity in Coronavirus disease 2019 (COVID-19) patients in comparison to conventional inflammatory biomarkers and clinical scores. PATIENTS AND METHODS: In an observational trial, COVID-19 acute respiratory distress syndrome (ARDS) patients were enrolled. MR-proADM, C-reactive protein (CRP), procalcitonin (PCT) and lactic acid (LA) were measured in all patients at admission (T0), at 24 hours (T1) and in the third (T3) and fifth day (T5) of hospitalization. The aims of this study were to determine the role of MR-proADM to detect patients with high risk of mortality and compare the prognostic value of MR-proADM with commonly used clinical scores (Sequential Organ Failure Assessment score-SOFA score, Acute Physiologic Assessment and Chronic Health Evaluation II score-APACHE II score, and Simplified Acute Physiological score II-SAPS II score). RESULTS: Twenty-one COVID-19 ARDS patients admitted to the Intermediate Care Unit (IMCU) were enrolled. The median MR-proADM values were 2.28, 2.41, 1.96 and 1.89 nmol/L at T0, T1, T3 and T5, respectively. The 30-day all-cause mortality rate was 52.4%. Mean MR-proADM T0 value was significantly higher in non-survivors compared with survivors (3.5 vs. 1.1 nmol/L, p < 0.05). No significant differences were found for the other inflammatory biomarkers. In terms of the area under the receiver-operating characteristic curve (AUC), MR-proADM showed a similar discriminatory power compared with APACHE II, SOFA and SAPS II score (0.81, 0.91, 0.70 and 0.78, respectively). The optimal MR-proADM cutpoint cut-off point was 1.07 nmol/L, which corresponds to a sensitivity of 91% and a specificity of 71%. CONCLUSIONS: MR- proADM, in addition to the clinical scores, could be useful to predict outcome in COVID-19 ARDS patients.