Changes in trace elements and metallothioneins levels and their relationship with clinical, biochemical, and inflammatory parameters in patients with COVID-19 during the early ICU phase

Background: The levels of trace elements and Metallothioneins (MTs) could play a key role in modulating the inflammatory reaction and pathogenesis of COVID-19. Their effects on clinical variables are of interest for the characterization and management of this disease. Thus, the present study aimed to investigate the association between circulating Iron (Fe), Zinc (Zn), Copper (Cu), Manganese (Mn), and MTs levels, as well as their relationship with clinical, biochemical, and inflammatory parameters in critical care patients with COVID-19 at early Intensive Care Unit (ICU) phase. Methods A total of 86 critically ill patients with COVID-19 were monitored from the first day of admission to the ICU until the third day of stay. Clinical parameters were retrieved from the hospital database. Biochemical and inflammatory parameters were analyzed following enzymatic colorimetry and immunoassay procedures. Serum samples were used to assess mineral levels by inductively coupled plasma-mass spectrometry and MTs levels by differential pulse voltammetric. Results Levels of Cu and MTs decreased (all P ≤ 0.046) after 3 days of ICU stay, increasing the prevalence of Cu deficient values from 50–65.3% (P = 0.015) on the third day of ICU stay. Fe and Zn were shown to have a predictive value for mortality and severity. Changes in Fe were directly related to changes in Cu and Mn (all r ≥ 0.266; P ≤ 0.019). In contrast, changes in MTs were inversely related to changes in Mn and albumin (all r≥–0.255; P ≤ 0.039). Conclusions The present study indicated a risk of trace element deficiencies related to different biochemical and clinical parameters. We suggest monitoring the mineral status and performing nutritional interventions, when appropriate, that could help to improve the altered parameters, such as inflammatory conditions and, thus, the prognosis in critically ill patients with COVID-19.