Background: Staphylococcus aureus bacteriuria (SABU) may represent multiple processes ranging from asymptomatic colonization to a marker of S. aureus bacteremia (SAB). Our objective was to describe SABU at a population-based level and determine patient characteristics associated with SAB. Methods: A retrospective study was performed using electronic databases. All urine cultures positive for S. aureus between 2010 and 2013 within the Calgary Health Zone were included. Patient characteristics were compared among patients with and without SAB and risk factors identified using multiple logistic regression modeling. Results: A total of 2540 urine cultures positive for S. aureus from 2054 patients were analyzed. The incidence of SABU was greatest among geriatric males with multiple comorbidities. SAB occurred in 175 (6.9%) of SABU patients. Those with SAB were more likely to be hospitalized, male, have a recent urinary procedure, have pure S. aureus culture in urine, and have laboratory findings suggesting systemic infection. Patients with isolated SABU were more likely to be ≥65 years, have dementia, and have abnormal urinalyses with pyuria and urine nitrites. In-hospital mortality in patients with SABU and SABU+SAB was 9.2% and 17.5%, respectively. Patients with SABU detected ≥48 hours before SAB had the highest risk of death. Conclusions: Less than 7% of patients with SABU have or will develop SAB. Characteristics associated with SABU were identified that established higher risk for systemic infection. Investigating SABU patients with these characteristics for systemic infection is warranted because a delay in diagnosis is associated with increased mortality.

Introduction. The ID NOW is FDA approved for the detection of SARS-CoV-2 in symptomatic individuals within the first 7 days of symptom onset for COVID-19 if tested within 1 h of specimen collection. Gap statement. Clinical data on the performance of the ID NOW are limited, with many studies varying in their study design and/or having small sample size. Aim. In this study we aimed to determine the clinical performance of the ID NOW compared to conventional RT-PCR testing. Methodology. Adults with COVID-19 in the community or hospital were recruited into the study. Paired throat swabs were collected, with one throat swab transported immediately in an empty sterile tube to the laboratory for ID NOW testing, and the other transported in universal transport media and tested by an in-house SARS-CoV-2 RT-PCR assay targeting the E gene. Results. In total, 133 individuals were included in the study; 129 samples were positive on either the ID NOW and/or RT-PCR. Assuming any positive result on either assay represents a true positive, positive per cent agreement (PPA) of the ID NOW compared to RT-PCR with 95 % confidence intervals was 89.1 % (82.0–94.1%) and 91.6 % (85.1–95.9%), respectively. When analysing individuals with symptom duration ≤7 days and who had the ID NOW performed within 1 h (n=62), ID NOW PPA increased to 98.2 %. Conclusion. Results from the ID NOW were reliable, especially when adhering to the manufacturer’s recommendations for testing.

: COVID-19 seroprevalence studies use serum/plasma samples to detect SARS-CoV-2 IgG. Data supporting alternate specimen types and freeze-thaw antibody stability is lacking. The stability of IgG and other immunoglobulins in multiple blood sample types stored in differing conditions and multiple freeze-thaw cycles (FTCs) was evaluated. : Serum, plasma, and heparinized-plasma samples were collected from COVID-19 recovered individuals. Samples underwent testing for SARS-CoV-2 antibodies upon collection, after each of 10–12 FTCs, and storage at -70°C, -20°C, 4°C, and room-temperature for 10–12 days using four high-throughput commercial assays, two rapid-test cassettes, a manual ELISA, and a surrogate neutralization assay. : All three specimen types were collected from 34 COVID-19 recovered seropositive individuals (≥21 days post-symptoms). Using the Architect and Liaison assays, a positive qualitative SARS-CoV-2 IgG result was detected daily up to 12 FTCs and up to 10 days of storage at different temperatures. An additional 25 plasma samples consistently demonstrated detection of SARS-CoV-2 antibodies daily after 12 FTCs and storage at -20°C using two rapid test cassette assays (SD Biosensor and Hangzhou All Test), manual (Beijing Wantai) and surrogate neutralization (GenScript) ELISAs, and two high-throughput assays (Roche Elecsys nucleocapsid and spike). IgM antibodies were less frequently detected by one of the rapid test cassette assays. : Serum, plasma, and heparinized-plasma constitute reliable samples for SARS-CoV-2 antibody detection. In particular, the IgG response was stable and reliably detected after multiple FTCs and storage at common laboratory conditions. IgM detection was variable due to the labile nature of this antibody class.

Frequent screening of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among asymptomatic populations using antigen-based point-of-care tests (APOCTs) is occurring globally with limited clinical performance data. The positive predictive value (PPV) of two APOCTs used in the asymptomatic screening of SARS-CoV-2 among health care workers (HCWs) at continuing care (CC) sites across AB, Canada, was evaluated. Between 22 February and 2 May 2021, CC sites implemented SARS-CoV-2 voluntary screening of their asymptomatic HCWs. On-site testing with Abbott Panbio or BD Veritor occurred on a weekly or twice-weekly basis.

Chronic Q fever is a potentially life-threatening infection from the intracellular, Gram-negativeCoxiella burnetii. It presents most commonly as endocarditis or vascular infection in people with underlying cardiac or vascular disease. We discuss a case of a 67-year-old male withCoxiella burnetiivascular infection of a perirenal abdominal aortic graft. The patient had a history of an abdominal aortic aneurysm (AAA) repair 5 years earlier. He presented with a 12 × 6 × 8 cm perirenal pseudoaneurysm and concomitant L1, L2, and L3 vertebral body discitis. He underwent an open repair which revealed a grossly infected graft perioperatively. Q fever serology revealed phase I serological IgG titer of 1 : 2048 and phase II 1 : 1024 consistent with chronic Q fever. Polymerase chain reaction (PCR) on infected vascular tissue was positive forC. burnetii. The patient was started on doxycycline and hydroxychloroquine with good clinical response and decreasing serological titers. Recognizing chronic Q fever is a difficult task as symptoms are nonspecific, exposure risk is difficult to ascertain, and diagnosis is hidden from conventional microbiological investigations. Its recognition, however, is critical asC. burnetiiis inherently resistant to standard empiric therapies used in cardiovascular infections.