Performance of the matrix-assisted laser desorption ionization time-of-flight mass spectrometry system for rapid identification of streptococci: a review.

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been developed as a new type of soft ionization mass spectrometry in recent years. An increasing number of clinical microbiological laboratories consider it as an innovative approach for bacterial identification. This study was undertaken in order to evaluate the use of MALDI-TOF MS for rapid identification of the clinical streptococci. A systematic review was conducted based on a literature search of the Medline and Embase databases. Fixed-effects models based on the P-value and the I-square were used for meta-analysis while considering the possibility of heterogeneity between studies. Statistical analyses were performed by using STATA 11.0. Twenty-seven studies covering 3,540 streptococci were included in our meta-analysis. The MALDI-TOF MS correctly identified the species of 96% (I2 = 92.8, P < 0.1) of the streptococci. The MALDI-TOF MS correctly identified the species of 99% of the Streptococcus pneumoniae (I2 = 85.2%, P < 0.1), 100% of the Streptococcus pyogenes (I2 = 32.8%, P > 0.1), and 100% of Streptococcus agalactiae (I2 = 20.7%, P > 0.2). What's more, it also had high confidence in other Streptococcus. But the accuracy of bovis needs to be improved. The overall performance of both MALDI-MS systems was different. Notably, the identifying accuracy rate of streptococci by VITEK MS was 98%, compared to 94% by the MALDI biotyper system. Interestingly, when analyzing the incorrect identification of MALDI-TOF MS, 36 out of the 38 strains of Streptococcus mitis/oralis were inaccurately identified as Streptococcus pneumoniae by the MALDI biotyper system. In conclusion, the results of this review indicated that MALDI-TOF MS could be a reliable and rapid method for identification of the streptococci.

First report of the qnrA determinant in Shigella sonnei isolated from China.

We investigated the first presence of qnrA among Shigella sonnei clinical isolates in Jiangsu Province, China. The qnrA-positive isolates coexisted with the mutation in gyrA at codon 83, these isolates were resistant to nalidixic acid and 22·2% (2 of 9) of them were resistant to norfloxacin.

Risk factors for prolongation of ileostomy closure operation.

OBJECTIVE: Understanding factors for prolonged operative time is essential for surgery. This study aims at identifying the factors related to prolonged ileostomy closure operation time. PATIENTS AND METHODS: The data of 88 patients who underwent ileostomy reversal in the Department of Gastrointestinal Surgery of Jiaxing First Hospital between January 2018 and October 2021 were retrospectively analyzed. Prolonged operation time was defined as operative time >65 minutes. The Chi-square test was used to compare data between patients with normal operative time (≤65 minutes) and patients with prolonged operative time. Univariate and multivariate logistic regression analyses were performed to identify the factors associated with prolonged ileostomy closure operation time. RESULTS: Among the 88 patients (mean age: 62.78 years), median ileostomy retention time was 127.50 (range: 61.00-1,192.00) days. The operation time ranged from 35.00 minutes to 125.00 minutes. Prolonged ileostomy closure time occurred in 41 (46.6%) patients. In univariate analysis, the factors associated with prolonged operation time were body mass index (BMI) ≥25 kg/m2, previous history of abdominal surgery, and manual suture. History of serious complications after the primary operation was associated with shorter operation time. In multivariate analysis, the independent risk factors for prolonged operation time were BMI ≥25 kg/m2 (OR = 4.552, 95% CI: 1.369-15.136, p = 0.013), previous history of abdominal surgery (OR = 4.377, 95% CI: 1.394-13.739, p = 0.011), and manual suture (OR = 3.941, 95% CI: 1.181-13.154, p = 0.026). CONCLUSIONS: Overweight, previous history of abdominal surgery, and manual suture appear to be risk factors for prolonged operative time for ileostomy closure.