Evaluation of matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) for the Identification of Group B Streptococcus

Abstract

Objective Group B Streptococcus (GBS) is a leading cause of neonatal meningitis and sepsis worldwide. Intrapartum antibiotics given to women carrying GBS are an effective means of reducing disease in the first week of life. Rapid and reliable tests are needed to accurately identify GBS from these women for timely intrapartum antibiotic administration to prevent neonatal disease. Many laboratories now use matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) by direct plating or cell lysis for the identification of GBS isolates. The cell lysis step increases time to results for clinical samples and is more complex to perform. Therefore, we seek to evaluate the sensitivity and specificity of the quicker and more rapid direct plating method in identifying GBS. Results We directly compared swab isolates analysed by both direct plating and cell lysis method and demonstrated that direct plating has a sensitivity and specificity of 0.97 and 1, respectively, compared to an additional cell lysis step. We demonstrated that MALDI-TOF MS can be successfully used for batch processing by the direct plating method which saves time. These results are reassuring for laboratories worldwide who seek to identify GBS from swabs samples as quickly as possible.

Rapid direct identification of positive paediatric blood cultures by MALDI-TOF MS technology and its clinical impact in the paediatric hospital setting

“…Low organism counts or competition from impurities may explain the lower confidence scores in poly-microbial samples. There have been very few studies focusing on the impact of rapid identification from MALDI-TOF MS for both the patient and the laboratory [4,5,[20][21][22][23][24].…”

CRISPR/Cas12a-Based Assay for the Rapid and High-Sensitivity Detection of Streptococcus Agalactiae Colonization in Pregnant Women with Premature Rupture of Membrane

“…The clinical performance of the 179 samples highlights the potential of the CRISPR-GBS assay as a promising assay for the identi cation of GBS, with a clinical sensitivity of 96.64% (144/149, 95% CI = 92.39-98.56%) and a clinical speci city of 100% (30/30, 95% CI = 88.65-100%), compared with the culture-MS method. Culture-MS method as a reference has been con rmed to be more sensitive and speci c than the conventional culture for GBS identi cation [8] [33][34][35]. Moreover, CRISPR-GBS demonstrated a high concordance of 98.88% with the RT-PCR assay.…”

<p>A Case Report of Cerebral Meningitis Caused by Penicillin-Non-Susceptible Group B <em>Streptococcus</em> in an Immunocompromised Adult Patient</p>

“…Lartigue et al reported that MALDI-TOF MS is 100% accurate for the identification of GBS, 27 and other previous studies have also demonstrated it to be a valuable tool for the identification of GBS with a high level of accuracy. [28][29][30][31] Therefore, we strongly believe that the isolated strain was GBS. Furthermore, the serotype of the isolated GBS in the present case was conformed as serotype Ib, using the anti-GBS serotype-specific serum.…”