Sickle Cell Trait and SARS-CoV-2-Induced Rhabdomyolysis: A Case Report.

BACKGROUND Rhabdomyolysis is a syndrome characterized by muscle necrosis and the subsequent release of intracellular muscle constituents into the bloodstream. Although the specific cause is frequently evident from the history or from the immediate events, such as a trauma, extraordinary physical exertion, or a recent infection, sometimes there are hidden risk factors that have to be identified. For instance, individuals with sickle cell trait (SCT) have been reported to be at increased risk for rare conditions, including rhabdomyolysis. Moreover, there have been a few case reports of SARS-CoV-2 infection-related rhabdomyolysis. CASE REPORT We present a case of a patient affected by unknown SCT and admitted with SARS-CoV-2 pneumonia, who suffered non-traumatic non-exertional rhabdomyolysis leading to acute kidney injury (AKI), requiring acute hemodialysis (HD). The patients underwent 13 dialysis session, of which 12 were carried out using an HFR-Supra H dialyzer. He underwent kidney biopsy, where rhabdomyolysis injury was ascertained. No viral traces were found on kidney biopsy samples. The muscle biopsy showed the presence of an "open nucleolus" in the muscle cell, which was consistent with virus-infected cells. After 40 days in the hospital, his serum creatinine was 1.62 mg/dL and CPK and Myoglobin were 188 U/L and 168 ng/mL, respectively; therefore, the patient was discharged. CONCLUSIONS SARS-CoV-2 infection resulted in severe rhabdomyolysis with AKI requiring acute HD. Since SARS-CoV-2 infection can trigger sickle-related complications like rhabdomyolysis, the presence of SCT needs to be ascertained in African patients.

microRNAs and Inflammatory Immune Response in SARS-CoV-2 Infection: A Narrative Review.

The current SARS-CoV-2 pandemic has emerged as an international challenge with strong medical and socioeconomic impact. The spectrum of clinical manifestations of SARS-CoV-2 is wide, covering asymptomatic or mild cases up to severe and life-threatening complications. Critical courses of SARS-CoV-2 infection are thought to be driven by the so-called "cytokine storm", derived from an excessive immune response that induces the release of proinflammatory cytokines and chemokines. In recent years, non-coding RNAs (ncRNAs) emerged as potential diagnostic and therapeutic biomarkers in both inflammatory and infectious diseases. Therefore, the identification of SARS-CoV-2 miRNAs and host miRNAs is an important research topic, investigating the host-virus crosstalk in COVID-19 infection, trying to answer the pressing question of whether miRNA-based therapeutics can be employed to tackle SARS-CoV-2 complications. In this review, we aimed to directly address ncRNA role in SARS-CoV-2-immune system crosstalk upon COVID-19 infection, particularly focusing on inflammatory pathways and cytokine storm syndromes.

Circulating miR-320b and miR-483-5p levels are associated with COVID-19 in-hospital mortality.

The stratification of mortality risk in COVID-19 patients remains extremely challenging for physicians, especially in older patients. Innovative minimally invasive molecular biomarkers are needed to improve the prediction of mortality risk and better customize patient management. In this study, aimed at identifying circulating miRNAs associated with the risk of COVID-19 in-hospital mortality, we analyzed serum samples of 12 COVID-19 patients by small RNA-seq and validated the findings in an independent cohort of 116 COVID-19 patients by qRT-PCR. Thirty-four significantly deregulated miRNAs, 25 downregulated and 9 upregulated in deceased COVID-19 patients compared to survivors, were identified in the discovery cohort. Based on the highest fold-changes and on the highest expression levels, 5 of these 34 miRNAs were selected for the analysis in the validation cohort. MiR-320b and miR-483-5p were confirmed to be significantly hyper-expressed in deceased patients compared to survived ones. Kaplan-Meier and Cox regression models, adjusted for relevant confounders, confirmed that patients with the 20% highest miR-320b and miR-483-5p serum levels had three-fold increased risk to die during in-hospital stay for COVID-19. In conclusion, high levels of circulating miR-320b and miR-483-5p can be useful as minimally invasive biomarkers to stratify older COVID-19 patients with an increased risk of in-hospital mortality.

Decreased serum levels of the inflammaging marker miR-146a are associated with clinical non-response to tocilizumab in COVID-19 patients.

Current COVID-19 pandemic poses an unprecedented threat to global health and healthcare systems. The most amount of the death toll is accounted by old people affected by age-related diseases that develop a hyper-inflammatory syndrome. In this regard, we hypothesized that COVID-19 severity may be linked to inflammaging. Here, we examined 30 serum samples from patients enrolled in the clinical trial NCT04315480 assessing the clinical response to a single-dose intravenous infusion of the anti-IL-6 receptor drug Tocilizumab (TCZ) in COVID-19 patients with multifocal interstitial pneumonia. In these serum samples, as well as in 29 age- and gender-matched healthy control subjects, we assessed a set of microRNAs that regulate inflammaging, i.e. miR-146a-5p, miR-21-5p, and miR-126-3p, which were quantified by RT-PCR and Droplet Digital PCR. We showed that COVID-19 patients who did not respond to TCZ have lower serum levels of miR-146a-5p after the treatment (p = 0.007). Among non-responders, those with the lowest serum levels of miR-146a-5p experienced the most adverse outcome (p = 0.008). Our data show that a blood-based biomarker, such as miR-146a-5p, can provide clues about the molecular link between inflammaging and COVID-19 clinical course, thus allowing to better understand the use of biologic drug armory against this worldwide health threat.