Shogo Hanai

PURPOSE: The effect of antibiotics administered before blood cultures performed in general internal medicine outpatient settings is not well known. PATIENTS AND METHODS: We conducted a retrospective case-control study including adult patients who underwent blood cultures in the general internal medicine outpatient department of a Japanese university hospital between 2016 and 2022. Patients with positive blood cultures were included as cases and matched patients with negative blood cultures were included as controls. Univariable and multivariable logistic regression analyses were performed. RESULTS: A total of 200 patients and 200 controls were included. Antibiotics were administered prior to blood culture in 20% of patients (79/400). Oral antibiotics were prescribed to 69.6% of the prior antibiotics (55/79). Prior antibiotic use was significantly lower among patients with positive than negative blood cultures (13.5% vs 26.0%, p = 0.002) and was an independent predictive factor in univariable (odds ratio, 0.44; 95% confidence interval, 0.26-0.73; p = 0.002) and multivariable (adjusted odds ratio, 0.31; 95% confidence interval, 0.15-0.63; p = 0.002) logistic regression models for positive blood culture. The area under the receiver operating characteristic (AUROC) curve of the multivariable model for predicting positive blood cultures was 0.86. CONCLUSION: There was a negative correlation between prior antibiotic use and positive blood cultures in the general internal medicine outpatient department. Therefore, physicians should interpret the negative results of blood cultures performed after the administration of antibiotics with care.

PURPOSE: The general internal medicine (GIM) department can be an effective diagnostic coordinator for undiagnosed outpatients. We investigated the contribution of GIM consultations to the diagnosis of patients admitted to specialty departments in hospitals in Japan that have not yet adopted a hospitalist system. PATIENTS AND METHODS: This single-center, retrospective observational study was conducted at a university hospital in Japan. GIM consultations from other departments on inpatients aged ≥20 years, from April 2016 to March 2021, were included. Data were extracted from electronic medical records, and consultation purposes were categorized into diagnosis, treatment, and diagnosis and treatment. The primary outcome was new diagnosis during hospitalization for patients with consultation purpose of diagnosis or diagnosis and treatment. The secondary outcomes were the purposes of consultation with the Diagnostic and Generalist Medicine department. RESULTS: In total, 342 patients were included in the analysis. The purpose of the consultations was diagnosis for 253 patients (74%), treatment for 60 (17.5%), and diagnosis and treatment for 29 patients (8.5%). In 282 consultations for diagnosis and diagnosis and treatment, 179 new diagnoses were established for 162 patients (57.5%, 95% confidence interval [CI], 51.5-63.3). CONCLUSION: The GIM department can function as a diagnostic consultant for inpatients with diagnostic problems admitted to other specialty departments in hospitals where hospitalist or other similar systems are not adopted.

BACKGROUND: Performing repeat blood cultures after an initial positive culture (ie, follow-up blood cultures [FUBCs]) in patients with gram-negative bacilli (GNB) bacteremia is controversial. We aimed to comprehensively review the association of FUBCs with improvement in patient-relevant clinical outcomes in GNB bacteremia. METHODS: We performed a systematic review and random-effects meta-analysis to calculate summary effect estimates. We used hazard ratios as the effect measure. The primary outcome was 30-day or in-hospital mortality, and secondary outcomes were length of treatment and length of hospital stay. We searched PubMed, Embase, and Cochrane Central Register of Controlled Trials (Central) without language restrictions from inception to April 29, 2022. Original clinical studies evaluating the association between FUBCs and mortality in adult patients with GNB bacteremia were included. FUBC details were reviewed. Two independent reviewers used the Risk of Bias in Non-randomised Studies of Interventions tool. RESULTS: We identified 9 eligible retrospective studies. In total, 7778 hospitalized patients with GNB bacteremia were included. The studies were clinically heterogeneous and had a critical risk of bias. The utilization of FUBCs varied across studies (18%-89%). Random-effects meta-analysis of covariate-adjusted estimates found that FUBC use was associated with reduced mortality. Although not a result of the meta-analysis, lengths of treatment and hospital stay were longer for patients with FUBCs than for those without. Adverse events were not reported. CONCLUSIONS: FUBC acquisition was associated with lower mortality and longer hospital stay and treatment duration in GNB bacteremia. The risk of bias was critical, and no firm data were available to support mechanisms.