Elevated markers of gut leakage and inflammasome activation in COVID-19 patients with cardiac involvement

BACKGROUND

A high proportion of COVID-19 patients have cardiac involvement, even those without known cardiac disease. Downregulation of angiotensin converting enzyme 2 (ACE2), a receptor for SARS-CoV-2 and the renin-angiotensin system, as well as inflammatory mechanisms have been suggested to play a role. ACE2 is abundant in the gut and associated with gut microbiota composition. We hypothesized that gut leakage of microbial products, and subsequent inflammasome activation could contribute to cardiac involvement in COVID-19 patients.

METHODS

Plasma levels of a gut leakage marker (LPS-binding protein, LBP), a marker of enterocyte damage (intestinal fatty acid binding protein, IFABP), a gut homing marker (CCL25, ligand for chemokine receptor CCR9) and markers of inflammasome activation (IL-1β, IL-18 and their regulatory proteins) were measured at three time points (day 1, 3-5 and 7-10) in 39 hospitalized COVID-19 patients and related to cardiac involvement.

RESULTS

Compared to controls, COVID-19 patients had elevated plasma levels of LBP and CCL25 but not IFABP, suggesting impaired gut barrier function and accentuated gut homing of T cells without excessive enterocyte damage. Levels of LBP were twice as high at baseline in patients with elevated cardiac markers compared with those without and remained elevated during hospitalization. Also, markers of inflammasome activation were moderately elevated in patients with cardiac involvement. LBP was associated with higher NT-pro-BNP levels, whereas IL-18, IL-18BP and IL-1Ra were associated with higher troponin levels.

CONCLUSION

Patients with cardiac involvement had elevated markers of gut leakage and inflammasome activation, suggestive of a potential gut-heart axis in COVID-19.

Measles virus genotyping an important tool in measles outbreak investigation in Norway, 2011

This study describes 33 laboratory-confirmed cases of measles that occurred in Norway in 2011, mainly among unvaccinated children between seven months and 10 years of age. Laboratory testing included detection of anti-measles IgM- and IgG antibodies by enzyme-linked immunosorbent assay (ELISA) and molecular detection and characterisation of measles virus by polymerase chain reaction (PCR) and sequencing. Epidemiological data and genotyping revealed that the measles cases originated from eight separate importations, resulting in four outbreaks and four sporadic cases. Except for the first outbreak which affected 18 cases, limited secondary spread occurred in each of the three other outbreaks. The outbreaks were caused by measles virus genotypes B3, D4 and D9, whereas genotypes D8 and B3 were detected in the sporadic cases. This study highlights that genetic characterisation of measles virus is an essential tool in the laboratory surveillance of measles, especially in countries like Norway which are approaching the measles elimination goal. The investigation revealed that importation of measles resulted in subsequent transmission within Norway to non-vaccinated individuals, and twelve cases occurred in healthcare settings, involving both staff and children. The four cases detected among healthcare workers (HCWs) emphasised that the coverage of measles-mumps-rubella (MMR) vaccination among healthcare personnel needs to be improved and both primary and secondary vaccine failure was demonstrated in two fully immunised HCWs.

Measles virus genotyping an important tool in measles outbreak investigation in Norway, 2011

This study describes 33 laboratory-confirmed cases of measles that occurred in Norway in 2011, mainly among unvaccinated children between seven months and 10 years of age. Laboratory testing included detection of anti-measles IgM- and IgG antibodies by enzyme-linked immunosorbent assay (ELISA) and molecular detection and characterisation of measles virus by polymerase chain reaction (PCR) and sequencing. Epidemiological data and genotyping revealed that the measles cases originated from eight separate importations, resulting in four outbreaks and four sporadic cases. Except for the first outbreak which affected 18 cases, limited secondary spread occurred in each of the three other outbreaks. The outbreaks were caused by measles virus genotypes B3, D4 and D9, whereas genotypes D8 and B3 were detected in the sporadic cases. This study highlights that genetic characterisation of measles virus is an essential tool in the laboratory surveillance of measles, especially in countries like Norway which are approaching the measles elimination goal. The investigation revealed that importation of measles resulted in subsequent transmission within Norway to non-vaccinated individuals, and twelve cases occurred in healthcare settings, involving both staff and children. The four cases detected among healthcare workers (HCWs) emphasised that the coverage of measles-mumps-rubella (MMR) vaccination among healthcare personnel needs to be improved and both primary and secondary vaccine failure was demonstrated in two fully immunised HCWs.

Ongoing outbreak of measles in Oslo, Norway, January–February 2011

Between 19 January and 17 February 2011, 10 cases of measles (eight laboratory-confirmed and two probable) were reported in Oslo with the majority of cases in a mainly unvaccinated immigrant community. Of these, two cases were identified outside the immigrant community, in Norwegian children.

Ongoing outbreak of measles in Oslo, Norway, January-February 2011

Between 19 January and 17 February 2011, 10 cases of measles (eight laboratory-confirmed and two probable) were reported in Oslo with the majority of cases in a mainly unvaccinated immigrant community. Of these, two cases were identified outside the immigrant community, in Norwegian children.

Fatal and mild primary dengue virus infections imported to Norway from Africa and south-east Asia, 2008-2010

Between 2008 and 2010, eight cases of viraemic dengue fever in travellers were diagnosed in Norway. They had returned from Eritrea, Thailand and Indonesia. All cases were primary dengue infections, seven non-complicated dengue fever and one dengue shock syndrome with a fatal outcome. Four patients were infected with dengue virus serotype 1, one with type 2 and three with type 3. Two cases from Thailand, the fatal case and the two imported from Eritrea were infected with type 1.

Oseltamivir-resistant influenza A(H1N1) viruses detected in Europe during season 2007-8 had epidemiologic and clinical characteristics similar to co-circulating susceptible A(H1N1) viruses

During the 2007-08 influenza season, high levels of oseltamivir resistance were detected among influenza A(H1N1) viruses ina number of European countries. We used surveillance data to describe influenza A(H1N1) cases for whom antiviral resistance testing was performed. We pooled data from national studies to identify possible risk factors for infection with a resistant virus and to ascertain whether such infections led to influenza illness of different severity. Information on demographic and clinical variables was obtained from patients or their physicians. Odds ratios for infection with an oseltamivir resistant virus and relative risks for developing certain clinical outcomes were computed and adjusted through multivariable analysis. Overall, 727 (24.3%) of 2,992 tested influenza A(H1N1) viruses from 22 of 30 European countries were oseltamivir-resistant. Levels of resistance ranged from 1% in Italy to 67% in Norway. Five countries provided detailed case-based data on 373 oseltamivir resistant and 796 susceptible cases. By multivariable analysis, none of the analysed factors was significantly associated with an increased risk of infection with anoseltamivir-resistant virus. Similarly, infection with an oseltamivir-resistant virus was not significantly associated with a different risk of pneumonia, hospitalisation or any clinical complication. The large-scale emergence of oseltamivir-resistant viruses in Europe calls for a review of guidelines for influenza treatment.

Oseltamivir-resistant influenza A(H1N1) viruses detected in Europe during season 2007-8 had epidemiologic and clinical characteristics similar to co-circulating susceptible A(H1N1) viruses

During the 2007-08 influenza season, high levels of oseltamivir resistance were detected among influenza A(H1N1) viruses in a number of European countries. We used surveillance data to describe influenza A(H1N1) cases for whom antiviral resistance testing was performed. We pooled data from national studies to identify possible risk factors for infection with a resistant virus and to ascertain whether such infections led to influenza illness of different severity. Information on demographic and clinical variables was obtained from patients or their physicians. Odds ratios for infection with an oseltamivir resistant virus and relative risks for developing certain clinical outcomes were computed and adjusted through multivariable analysis. Overall, 727 (24.3%) of 2,992 tested influenza A(H1N1) viruses from 22 of 30 European countries were oseltamivir-resistant. Levels of resistance ranged from 1% in Italy to 67% in Norway. Five countries provided detailed case-based data on 373 oseltamivir resistant and 796 susceptible cases. By multivariable analysis, none of the analysed factors was significantly associated with an increased risk of infection with an oseltamivir-resistant virus. Similarly, infection with an oseltamivir-resistant virus was not significantly associated with a different risk of pneumonia, hospitalisation or any clinical complication. The large-scale emergence of oseltamivir-resistant viruses in Europe calls for a review of guidelines for influenza treatment.