Investigation of different methods in rapid microbial identification directly from positive blood culture bottles by MALDI-TOF MS.

Many methods are being tried for rapid and accurate identification of sepsis-causing microorganisms. We analyzed the performance of three different preparation methods [MBT Sepsityper IVD Kit (Bruker Daltonics GmbH, Germany), sodium dodecyl sulfate (SDS) lysis, and differential centrifugation with protein extraction (Centrifugation +PE)] and compared in standard and Sepsityper modules of the Bruker Biotyper MALDI-TOF MS for direct identification of bacteria from 240 positive blood culture bottles of BACTEC FX (Becton Dickinson, USA). By using the standard module, correct identification at species level (score ≥2) was done in 46.7% of the samples with SDS lysis, 44.2% with centrifugation +PE, and 25.4% with the Sepsityper kit. These ratios at the genus level (score range 1.70-1.99) were 34.6%, 31.3%, and 32.5%, respectively. With SDS lysis (195), more bacteria were identified correctly than centrifugation +PE (181) and the Sepsityper kit (139). A statistically significant difference was found between SDS and the Sepsityper kit and Centrifugation +PE and the Sepsityper kit (P < 0.001, both). By using the Sepsityper module, correct identification at species level (score ≥1.8) was determined in 74.2% of the samples with SDS lysis and centrifugation +PE each and 55% with the Sepsityper kit. These ratios at the genus level (score range 1.60-1.79) were 16.3%, 10%, and 19.2%, respectively. SDS lysis (217) had significantly higher identification rates than centrifugation +PE (202) and the Sepsityper kit (178) (P = 0.028 and P < 0.001). A statistically significant difference was also observed between centrifugation +PE and the Sepsityper kit (P < 0.001). Best performance was obtained with SDS lysis among the methods. Although better performance was achieved by using Sepsityper software module, risk of misidentification should not be ignored. IMPORTANCE: Sepsis is a life-threatening condition, and rapid and accurate identification of the causative microorganisms from blood cultures is crucial for timely and effective treatment. Although there are many studies on direct identification from blood cultures with MALDI-TOF MS, further standardization is still needed. In our study, we analyzed the performance of three different preparation methods and compared by using two analysis modules of the Bruker Biotyper MALDI-TOF MS for direct identification of bacteria from numerous positive blood culture bottles. The literature reports a limited number of studies that compare different preparation methods for direct blood culture identification, processing a large number of blood samples concurrently and evaluating the same samples as in our study. Moreover, although SDS is used very frequently in medical laboratories, there are few studies on direct identification from blood culture bottles. In our study, the highest correct identification rate was observed with the SDS method.

Evaluation of voriconazole related adverse events in pediatric patients with hematological malignancies.

BACKGROUND: Despite therapeutic drug monitoring and pharmacogenetic-guided dose selection are recommended for pediatric patients, safety of voriconazole is mostly monitored by clinical assessment. Having comprehensive knowledge of safety profile and distinguishing incidental events from the reactions that are truly related to voriconazole use are crucial for safer and uninterrupted treatment. OBJECTIVES: This study aimed to address adverse reactions during the first month of voriconazole use by systematically evaluating retrospective records of all adverse events. Patients/Methods: It is a single-center, retrospective analysis of patients who received voriconazole from 1 September 2010 to 1 September 2020. Severity of abnormal findings in medical records were systematically graded. Causality between voriconazole and the events was evaluated by Liverpool Causality Assessment Tool (LCAT), Naranjo Algorithm and World Health Organization Causality Assessment System. The events with possible or probable causal relation to voriconazole are classified as adverse reaction. RESULTS: Records of 45 patients included in the study. The overall frequency of adverse reactions was 51.1%. Hepatobiliary laboratory adverse reactions identified in 48.9% of the patients and led to treatment discontinuation in 20.0%. Amylase and lipase elevation (2.2%), ventricular extra systoles (2.2%), hallucination and nightmares (2.2%) were other adverse reactions. CONCLUSIONS: Hepatobiliary abnormalities were the most common adverse reactions and the most common cause of treatment discontinuation. For safer treatment in critically ill patients, the dose should be personalized. To clearly identify the accurate frequency and the causality of all adverse reactions, prospective studies with much larger sample size are needed.

Clinical characteristics and risk factors for 28-day mortality in critically ill patients with COVID-19: a retrospective cohort study

Background: To date, the coronavirus disease 2019 (COVID-19) caused more than 2.6 million deaths all around the world. Risk factors for mortality remain unclear. The primary aim was to determine the independent risk factors for 28-day mortality. Materials and methods: In this retrospective cohort study, critically ill patients (≥ 18 years) who were admitted to the intensive care unit due to COVID-19 were included. Patient characteristics, laboratory data, radiologic findings, treatments, and complications were analyzed in the study. Results: A total of 249 patients (median age 71, 69.1% male) were included in the study. 28-day mortality was 67.9% (n = 169). The median age of deceased patients was 75 (66­81). Of them, 68.6% were male. Cerebrovascular disease, dementia, chronic kidney disease, and malignancy were significantly higher in the deceased group. In the multivariate analysis, sepsis/septic shock (OR, 15.16, 95% CI, 3.96­58.11, p < 0.001), acute kidney injury (OR, 4.73, 95% CI, 1.55­14.46, p = 0.006), acute cardiac injury (OR, 9.76, 95% CI, 1.84­51.83, p = 0.007), and chest CT score higher than 15 (OR, 4.49, 95% CI, 1.51-13.38, p = 0.007) were independent risk factors for 28-day mortality. Conclusion: Early detection of the risk factors and the use of chest CT score might improve the outcomes in patients with COVID-19.

Primary Cutaneous Aspergillosis in Immunocompetent Adults: Three Cases and a Review of the Literature.

Primary cutaneous aspergillosis (PCA) can rarely affect immunocompetent people. There is limited knowledge about the prevalence, diagnosis and management of the disease because there are only case reports or small case series in the literature. For this reason, the diagnosis and treatment of three immunocompetent adult patients diagnosed with PCA were discussed by reviewing the literature. In the current report, in addition to treatment with voriconazole for 8-12 weeks we performed repeated surgical debridement for the treatment of these cases. After two negative tissue cultures, the wounds were either successfully closed primarily or reconstructed using a skin graft. Management of PCA cases will become easier as more reports and further studies of PCA contribute to our shared knowledge. Currently, the most appropriate management approach is to make individualized treatment decisions according to the patients' clinical features and treatment response which includes several surgical debridement as well as antifungal therapy.