Lewis and ABO histo-blood types and the secretor status of patients hospitalized with COVID-19 implicate a role for ABO antibodies in susceptibility to infection with SARS-CoV-2.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) targets the respiratory and gastric epithelium, causing coronavirus disease 2019 (COVID-19). Tissue antigen expression variations influence host susceptibility to many infections. This study aimed to investigate the closely linked Lewis (FUT3) and ABO histo-blood types, including secretor (FUT2) status, to infections with SARS-CoV-2 and the corresponding severity of COVID-19. STUDY DESIGN AND METHODS: Patients (Caucasians, n = 338) were genotyped for ABO, FUT3, and FUT2, and compared to a reference population of blood donors (n = 250,298). The association between blood types and severity of COVID-19 was addressed by dividing patients into four categories: hospitalized individuals in general wards, patients admitted to the intensive care unit with and without intubation, and deceased patients. Comorbidities were considered in subsequent analyses. RESULTS: Patients with blood type Lewis (a-b-) or O were significantly less likely to be hospitalized (odds ratio [OR] 0.669, confidence interval [CI] 0.446-0.971, OR 0.710, CI 0.556-0.900, respectively), while type AB was significantly more prevalent in the patient cohort (OR 1.519, CI 1.014-2.203). The proportions of secretors/nonsecretors, and Lewis a+ or Lewis b+ types were consistent between patients and controls. The analyzed blood groups were not associated with the clinical outcome as defined. DISCUSSION: Blood types Lewis (a-b-) and O were found to be protective factors, whereas the group AB is suggested to be a risk factor for COVID-19. The antigens investigated may not be prognostic for disease severity, but a role for ABO isoagglutinins in SARS-CoV-2 infections is strongly suggested.

Contrast-enhanced ultrasound detects gallbladder perforation in a patient with acute abdominal pain.

We present the case of a patient with abdominal pain, in which gallbladder perforation was detected by contrast-enhanced ultrasound. A 90-year-old patient presented to the emergency department with a complaint of acute abdominal pain and vomiting. An abdominal ultrasound revealed a thickened gallbladder wall and small amounts of perihepatic fluid. Because these findings were suspicious for gallbladder perforation and contrast-enhanced computed tomography could not be performed because of a history of monoclonal gammopathy, a contrast-enhanced ultrasound scan was performed. After the administration of 2.5 mL of SonoVue (Bracco, Milan, Italy), a defect of the gallbladder wall was detected. The patient underwent laparotomy, on which the diagnosis of gallbladder perforation was confirmed.

Validation of a simple risk stratification tool for COVID-19 mortality.

Risk prediction is an essential part of clinical care, in order to allocate resources and provide care appropriately. During the COVID-19 pandemic risk prediction became a matter of political and public debate as a major clinical need to guide medical and organizational decisions. We previously presented a simplified risk stratification score based on a nomogram developed in Wuhan, China in the early phase of the pandemic. Here we aimed to validate this simplified risk stratification score in a larger patient cohort from one city in Austria. Age, oxygen saturation, C-reactive protein levels and creatinine levels were used to estimate the in-hospital mortality risk for COVID-19 patients in a point based score: 1 point per age decade, 4 points for oxygen saturation <92%, 8 points for CRP > 10 mg/l and 4 points for creatinine > 84 µmol/l. Between June 2020 and March 2021, during the "second wave" of the pandemic, 1,472 patients with SARS-CoV-2 infection were admitted to two hospitals in Graz, Austria. In 961 patients the necessary dataset to calculate the simplified risk stratification score was available. In this cohort, as in the cohort that was used to develop the score, a score above 22 was associated with a significantly higher mortality (p < 0.001). Cox regression confirmed that an increase of one point in the risk stratification score increases the 28-day-mortality risk approximately 1.2-fold. Patients who were categorized as high risk (≥22 points) showed a 3-4 fold increased mortality risk. Our simplified risk stratification score performed well in a separate, larger validation cohort. We therefore propose that our risk stratification score, that contains only two routine laboratory parameter, age and oxygen saturation as variables can be a useful and easy to implement tool for COVID-19 risk stratification and beyond. The clinical usefulness of a risk prediction/stratification tool needs to be assessed prospectively (https://www.cbmed.at/covid-19-risk-calculator/).

Identification of a novel variant of hepatitis E virus in Austria: sequence, phylogenetic and serological analysis.

We isolated a novel hepatitis E virus (HEV-Au1) variant from a patient in Austria suffering from acute viral hepatitis, who had no known risk factors for acquiring hepatitis E. The clinical presentation and initial serological findings have been reported previously. In this paper we report the results of sequence and phylogenetic analysis of HEV products from viral RNA isolated from acute phase serum. The results show that HEV-Au1 is significantly divergent from other HEV isolates. The nucleotide identity of analysed fragments from the novel isolate ranges from 76.6 to 78.4% when compared to isolates from endemic regions and 84.6 to 87.9% when compared to isolates from non-endemic regions. Divergent results were obtained when serum samples taken from the convalescent phase of disease were tested with three different immunoassays (EIAs). An EIA based on United States isolate-specific peptides showed enhanced reactivity whereas EIAs based on recombinant proteins derived from prototype HEV strains from Burma and Mexico were unable to detect antibodies to HEV (anti-HEV) in late phase serum. The findings verify the presence of an additional HEV variant in an industrialized country and provide information about possible problems in detecting anti-HEV.