Comparison of bloodstream infections due to Corynebacterium striatum, MRSA, and MRSE.

BACKGROUND: Corynebacterium striatum (C. striatum), a common skin and mucosal colonizer, is increasingly considered as an opportunistic pathogen causing bloodstream infections (BSIs). This study aims to investigate the clinical features and outcomes of C. striatum-BSI. METHODS: We included hospitalized cases with C. striatum-positive blood cultures from January 2014 to June 2022 and classified them into C. striatum-BSI group and contamination group; Clinical characteristics, treatments, and outcomes were compared between the C. striatum-BSI group and contamination group, Methicillin-resistant Staphylococcus aureus (MRSA)-BSI and Methicillin-resistant Staphylococcus epidermidis (MRSE)-BSI. RESULTS: Fifty-three patients with positive C. striatum blood cultures were identified. Among them, 25 patients were classified as C. striatum-BSI, with 21 as contamination cases. And 62 cases of MRSA-BSI and 44 cases of MRSE-BSI were identified. Compared to the contaminated group, the C. striatum-BSI group had a shorter time to positivity of blood cultures (27.0 h vs. 42.5 h, P = 0.011). C. striatum-BSI group had a longer time to positivity (27 h) when compared to both the MRSA (20 h) and MRSE groups (19 h) (p < 0.05). Appropriate therapy within 24 h of BSI onset was significantly lower in the C. striatum group (28%) compared to the MRSA (64.5%) and MRSE (65.9%) groups (p < 0.005). The 28-day mortality was higher in the C. striatum group (52.0%) compared to the MRSA (25.8%) and MRSE (18.2%) groups.  CONCLUSIONS: Given the distinct characteristics of C. striatum-BSI, including a longer time to positivity than other Gram-positive bacteria and higher mortality rates, we suggest prescribing early appropriate antibiotics if C. striatum-BSI is suspected.

Comparison of different criteria of metagenomic next-generation sequencing for the diagnosis of invasive pulmonary aspergillosis in critically ill patients.

OBJECTIVE: To compare different criteria of Metagenomic Next-Generation Sequencing (mNGS) in bronchoalveolar lavage fluid (BALF) for diagnosing invasive pulmonary aspergillosis (IPA). METHODS: We compared the diagnostic agreement and performances of six BALF mNGS-derived criteria (SDSMRN>1, SDSMRN≥3, SMRN≥10, SMRN≥50, RPM ratio≥10, and relative abundance of genus>30 %) in pneumonia patients. RESULTS: A total of 115 patients were analyzed, with 28 identified with IPA. Diagnostic agreement among the six mNGS-derived criteria was moderate, with a Cohen's kappa of 0.577(P < 0.001). mNGS-derived criteria had low sensitivity ranging from 21.4 % to 57.1 % and high specificity from 88 % to 92 %. The optimal threshold of SDSMRN, SMRN, RPM ratio, and relative abundance of genus for diagnosing IPA were 5, 0.25, 8, and 20 %, respectively. Although using the optimal threshold, the sensitivity of mNGS is lower than 50 %. CONCLUSIONS: All mNGS-derived criteria had low sensitivity for diagnosing IPA. A combination of mNGS and conventional mycological tests may be the best diagnostic strategy.

Validation of an ICD-Based Algorithm to Identify Sepsis: A Retrospective Study.

Background: Sepsis surveillance was important for resources allocation, prevention, and development of health policy. Objective: The aim of the study was to validate a modified International Classification of Diseases (ICD)-10 based algorithm for identifying hospitalized patients with sepsis. Methods: We retrospectively analyzed a prospective, single-center cohort of adult patients who were consecutively admitted to one medical ICU ward and ten non-ICU wards with suspected or confirmed infections during a 6-month period. A modified ICD-10 based algorithm was validated against a reference standard of Sequential Organ Failure Assessment (SOFA) score based on Sepsis-3. Sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and areas under the receiver operating characteristic curves (AUROCs) were calculated for modified ICD-10 criteria, eSOFA criteria, Martin's criteria, and Angus's criteria. Results: Of the 547 patients in the cohort, 332 (61%) patients met Sepsis-3 criteria and 274 (50%) met modified ICD-10 criteria. In the ICU setting, modified ICD-10 criteria had SE (84.47%), SP (88.57%), PPV (95.60), and NPV (65.96). In non-ICU settings, modified ICD-10 had SE (64.19%), SP (80.00%), PPV (80.33), and NPV (63.72). In the whole cohort, the AUROCs of modified ICD-10 criteria, eSOFA, Angus's criteria, and Martin's criteria were 0.76, 0.75, 0.62, and 0.62, respectively. Conclusion: This study demonstrated that modified ICD-10 criteria had higher validity compared with Angus's criteria and Martin's criteria. Validity of the modified ICD-10 criteria was similar to eSOFA criteria. Modified ICD-10 algorithm can be used to provide an accurate estimate of population-based sepsis burden of China.