Diagnostic performance of matrix-assisted laser desorption ionisation time-of-flight mass spectrometry in blood bacterial infections: a systematic review and meta-analysis.
BACKGROUND
Matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) has shown promise in decreasing time to identification of causative organisms compared to traditional methods; however, the utility of MALDI-TOF MS in a heterogeneous clinical setting is uncertain.


OBJECTIVE
To perform a systematic review on the operational performance of the Bruker MALDI-TOF MS system and evaluate published cut-off values compared to traditional blood cultures.


METHODS
A comprehensive literature search was performed. Studies were included if they performed direct MALDI-TOF MS analysis of blood culture specimens in human patients with suspected bacterial infections using the Bruker Biotyper software. Sensitivities and specificities of the combined studies were estimated using a hierarchical random effects linear model (REML) incorporating cut-off scores of ≥1.7 and ≥2.0.


RESULTS
Fifty publications were identified, with 11 studies included after final review. The estimated sensitivity utilising a cut-off of ≥2.0 from the combined studies was 74.6% (95% CI = 67.9-89.3%), with an estimated specificity of 88.0% (95% CI = 74.8-94.7%). When assessing a cut-off of ≥1.7, the combined sensitivity increases to 92.8% (95% CI = 87.4-96.0%), but the estimated specificity decreased to 81.2% (95% CI = 61.9-96.6%).


CONCLUSIONS
In this analysis, MALDI-TOF MS showed acceptable sensitivity and specificity in bacterial speciation with the current recommended cut-off point compared to blood cultures; however, lowering the cut-off point from ≥2.0 to ≥1.7 would increase the sensitivity of the test without significant detrimental effect on the specificity, which could improve clinician confidence in their results.
a Department of Emergency Medicine , University of Mississippi Medical Center , Jackson , MS , USA ;
Jamie S
JS
Scott
a Department of Emergency Medicine , University of Mississippi Medical Center , Jackson , MS , USA ;
Sarah A
SA
Sterling
a Department of Emergency Medicine , University of Mississippi Medical Center , Jackson , MS , USA ;
Harrison
H
To
b Center of Biostatistics and Bioinformatics, University of Mississippi Medical Center , Jackson , MS , USA.
Samantha R
SR
Seals
a Department of Emergency Medicine , University of Mississippi Medical Center , Jackson , MS , USA ;
Alan E
AE
Jones
D016470:Bacteremia / Q000175:diagnosis / Q000382:microbiology; D001431:Bacteriological Techniques; D006801:Humans; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
Bacterial infections; MALDI-TOF MS; blood culture; matrix-assisted laser desorption ionisation time-of-flight mass spectrometry; sepsis