Integration of FDG-PET/CT in the Diagnostic Workup for Staphylococcus aureus Bacteremia: A Prospective Interventional Matched-cohort Study.

BACKGROUND: Staphylococcus aureus bacteremia (SAB) is uniquely characterized by focal pyogenic complications that might not be apparent clinically. We investigated the benefit of adding fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in the workup of patients with SAB. METHODS: In a matched-cohort study patients with SAB (intervention group) were prospectively recruited to undergo FDG-PET/CT 7-14 days after diagnosis. Treatment was directed by FDG-PET/CT findings. Clinical outcomes were compared with a control group of patients with SAB who had not undergone FDG-PET/CT, matched by age, Charlson score, methicillin susceptibility, and survival duration to FDG-PET/CT. The primary outcome was 90-day mortality. Residual confounding was controlled through regression analyses. RESULTS: During the study period 149 patients with 151 separate episodes of SAB underwent FDG-PET/CT and were compared with 150 matched patients with 151 SAB episodes. Patients in the intervention group acquired infections more frequently in the community and had less frequently solid malignancies and more frequently high-risk SAB. Ninety-day mortality in the intervention group was significantly lower than in the control group (21/151 [13.9%] vs 43/151 [28.5%], P = .002). The difference remained significant in a subgroup analysis of patients with community-onset infections without malignancy and among patients with low-risk SAB. Controlling for other risk factors for mortality, FDG-PET/CT performance among all patients was independently associated with lower mortality (OR, .39; 95% CI, .18-.84). Patients in the intervention group had longer duration of treatment and more focus control procedures performed compared with the control group. CONCLUSIONS: FDG-PET/CT in patients with SAB seems to improve survival through guidance of treatment duration and co-interventions.

Predictors of infectious foci on FDG PET/CT in Staphylococcus aureus bacteremia.

We looked for predicting factors for the detection of infectious foci on 18F-fluorodeoxyglucose-positron emission tomography in combination with computed tomography (FDG PET/CT) among patients with Staphylococcus aureus bacteremia (SAB) who participated in an interventional study that was conducted at Rambam Health Care Campus, between July 1, 2015 and February 1, 2019. The primary outcome was an infectious focus detected by FDG PET/CT. Independent predictors for detection of focal infection were identified using univariate followed by a logistic regression multivariate analysis. We included 149 patients with 151 separate episodes of SAB who underwent FDG-PET/CT. Focal infections were detected in 107 patients (70.8%). Independent predictors for focal infection detection were community acquisition of bacteremia with odds ratio (OR) 3.03 [95% confidence interval (CI) 1.04-8.77], p-0.042 and C reactive protein (CRP) with OR 1.09 [95% CI 1.04-1.14], p < 0.001. Primary bacteremia was inversely associated with focal infection detection with OR 0.27 [0.10-0.69], p = 0.007, as were the pre-scan blood glucose levels OR 0.9 [0.98-0.99], p-0.004. The latter stayed significant in the subgroup of patients with diabetes mellitus. To conclude, patients with community-acquired bacteremia or high CRP levels should be carefully investigated for focal infection. Patients who present with primary bacteremia seem to be at low risk for focal infection.

A Case of Severe COVID-19 Pneumonia Diagnosed in Bronchoscopy With Negative Repeated Nasopharyngeal Swabs.

Coronavirus disease 2019 (COVID-19) is a worldwide pandemic that had emerged in China since December 2019. The disease affects all age groups, with clinical manifestations in the spectrum from asymptomatic to rapidly lethal multi-organ failure, mainly involving the respiratory system. Diagnosis is confirmed mainly by a positive real-time polymerase chain reaction (PCR) nasopharyngeal swab. It is highly recommended to avoid performing invasive procedures in COVID-19 subjects to prevent the potential for dissemination of the pathogen. Treatment consists in particular of respiratory support and symptom relief. Dexamethasone is widely used with encouraging response. There were no cases in the literature that were diagnosed with positive reverse transcription-polymerase chain reaction (RT-PCR) testing only from fluid of involved organs, while repeated nasopharyngeal swabs returned negative for COVID-19. We here describe a case of COVID-19 that presented with moderate-severe pulmonary involvement, diagnosed by RT-PCR testing from broncho-alveolar lavage, while several nasopharyngeal swabs were consistently negative. The patient experienced no improvement under wide-spectrum antibiotics administered initially, and greatly improved after receiving systemic corticosteroids. One can realize from our case that COVID-19 could not be ruled out upon repeated negative RT-PCR nasopharyngeal swabs, and in subjects with highly suspected COVID-19, it is justified to perform invasive procedures, but still using maximal protective measures.