Molecular epidemiology and outcome of carbapenem-resistant Enterobacterales in Saudi Arabia

Background

The burden of carbapenem resistance is not well studied in the Middle East. We aimed to describe the molecular epidemiology and outcome of carbapenem-resistant Enterobacterales (CRE) infections from several Saudi Arabian Centers.

Methods

This is a multicenter prospective cohort study conducted over a 28-month period. Patients older than 14 years of age with a positive CRE Escherichia coli or Klebsiella pneumoniae culture and a clinically established infection were included in this study. Univariate and multivariable logistic models were constructed to assess the relationship between the outcome of 30-day all-cause mortality and possible continuous and categorical predictor variables.

Results

A total of 189 patients were included. The median patient age was 62.8 years and 54.0% were male. The most common CRE infections were nosocomial pneumonia (23.8%) and complicated urinary tract infection (23.8%) and 77 patients (40.7%) had CRE bacteremia. OXA-48 was the most prevalent gene (69.3%). While 100 patients (52.9%) had a clinical cure, 57 patients (30.2%) had died within 30 days and 23 patients (12.2%) relapsed. Univariate analysis to predict 30-day mortality revealed that the following variables are associated with mortality: older age, high Charlson comorbidity index, increased Pitt bacteremia score, nosocomial pneumonia, CRE bacteremia and diabetes mellitus. In multivariable analysis, CRE bacteremia remained as an independent predictor of 30 day all-cause mortality [AOR and 95% CI = 2.81(1.26–6.24), p = 0.01].

Conclusions

These data highlight the molecular epidemiology and outcomes of CRE infection in Saudi Arabia and will inform future studies to address preventive and management interventions.

Early use of tocilizumab in solid organ transplant recipients with COVID-19: A retrospective cohort study in Saudi Arabia

BACKGROUND

Tocilizumab was studied to reduce cytokine syndrome in patients with severe COVID-19 pneumonia in solid organ transplant (SOT) recipients with conflicting results. We aim to study the early use of tocilizumab in SOT with COVID-19 pneumonia on low flow oxygen.

METHODS

This is a retrospective cohort study that was conducted in two transplant centers in Saudi Arabia among 46 SOT with COVID-19 comparing 21 patients who received tocilizumab to 25 patients who received standard of care. Their clinical characteristics and outcomes were described.

RESULTS

Compared to patients who received standard of care, patients in the tocilizumab group were older (60.2 ± 12.8 vs. 48.6 ± 12.3, p = .003), had higher ferritin (862.1 ± 919.1 vs. 414 ± 447.3, p = .025) and C-reactive protein (CRP) (85 ± 83.1 vs. 42.9 ± 57.3, p = .012). More patients in the tocilizumab group required high flow oxygen (38.1% vs. 8.0%, p = .028) compared to patients on standard of care. There were no differences in mortality or mechanical ventilation requirement. Hospital stay was significantly shorter in the tocilizumab group than the standard of care group (9.6 ± 7.4 vs. 20.7 ± 11.7, p < .001).

CONCLUSIONS

Early use of tocilizumab in SOT was associated with a shorter hospital stay. There was no difference in mortality rate and the requirement for mechanical ventilation in both groups.

Test-based de-isolation in COVID-19 immunocompromised patients: Cycle threshold value versus SARS-CoV-2 viral culture

BACKGROUND

Immunocompromised patients with coronavirus disease 2019 (COVID-19) have prolonged infectious viral shedding for more than 20 days. A test-based approach is suggested for de-isolation of these patients.

METHODS

The strategy was evaluated by comparing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load (cycle threshold (Ct) values) and viral culture at the time of hospital discharge in a series of 13 COVID-19 patients: six immunocompetent and seven immunocompromised (five solid organ transplant patients, one lymphoma patient, and one hepatocellular carcinoma patient).

RESULTS

Three of the 13 (23%) patients had positive viral cultures: one patient with lymphoma (on day 16) and two immunocompetent patients (on day 7 and day 11). Eighty percent of the patients had negative viral cultures and had a mean Ct value of 20.5. None of the solid organ transplant recipients had positive viral cultures.

CONCLUSIONS

The mean Ct value for negative viral cultures was 20.5 in this case series of immunocompromised patients. Unlike those with hematological malignancies, none of the solid organ transplant patients had positive viral cultures. Adopting the test-based approach for all immunocompromised patients may lead to prolonged quarantine. Large-scale studies in disease-specific populations are needed to determine whether a test-based approach versus a symptom-based approach or a combination is applicable for the de-isolation of various immunocompromised patients.

Seroprevalence of neutralizing antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among healthcare workers in Makkah, Saudi Arabia

OBJECTIVE

The new coronavirus disease 2019 (COVID-19) is a major health problem worldwide. The surveillance of seropositive individuals serves as an indicator to the extent of infection spread and provides an estimation of herd immunity status among population. Reports from different countries investigated this issue among healthcare workers (HCWs) who are "at risk" and "sources of risk" for COVID-19. This study aims to investigate the seroprevalence of COVID-19 among HCWs in one of the COVID-19 referral centers in Makkah, Saudi Arabia using three different serological methods.

METHODS

In-house developed enzyme-linked immunoassay (ELISA), commercially available electro-chemiluminescence immunoassay (ECLIA), and microneutralization (MN) assay were utilized to determine the seroprevalence rate among the study population. 204 HCWs participated in the study. Both physicians and nurses working in the COVID-19 and non COVID-19 areas were included. Twelve out of 204 were confirmed cases of COVID-19 with variable disease severity. Samples from recovered HCWs were collected four weeks post diagnosis.

RESULTS

The overall seroprevalence rate was 6.3% (13 out of 204) using the in-house ELISA and MN assay and it was 5.8% (12 out of 204) using the commercial ECLIA. Among HCWs undiagnosed with COVID-19, the seroprevalence was 2% (4 out 192). Notably, neutralizing antibodies were not detected in 3 (25%) out 12 confirmed cases of COVID-19.

CONCLUSIONS

Our study, similar to the recent national multi-center study, showed a low seroprevalence of SARS-Cov-2 antibodies among HCWs. Concordance of results between the commercial electro-chemiluminescence immunoassay (ECLIA), in-house ELISA and MN assay was observed. The in-house ELISA is a promising tool for the serological diagnosis of SARS-CoV-2 infection. However, seroprevalence studies may underestimate the extent of COVID-19 infection as some cases with mild disease did not have detectable antibody responses.