Diagnostic Performance of MALDI-TOF MS Compared to Conventional Microbiological Cultures in Patients with Suspected Endophthalmitis

ABSTRACT

Purpose: To evaluate the performance and speed of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) when identifying the pathogenic microorganism of endophthalmitis compared to conventional microbiological culturing.

Methods: Forty-four patients with suspected endophthalmitis who had undergone vitrectomy were enrolled. Vitreous specimen was analyzed using either conventional culturing or MALDI-TOF MS.

Results: The identification rates of the conventional microbiological culture and MALDI-TOF MS were 45.5% (20/44) and 65.9% (29/44), respectively (Kappa value 0.787, P < 0.000). The mean detection times by the standard culturing method and MALDI-TOF MS were 5.39 ± 0.56d and 3.17 ± 0.40d (P < 0.001). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MALDI-TOF MS were 70.59%, 54.17%, 80.00%, and 86.67%, respectively. Polymicrobial endophthalmitis was identified in 6.82% of the patients (3/44) using conventional microbiological culturing. However, MALDI-TOF MS failed to identify any polymicrobial infection.

Conclusions: With a higher sensitivity, acceptable specificity and a shorter detection time, MALDI-TOF MS was an efficient technique for the rapid identification of a pathogenic microorganism in endophthalmitis.

Keywords:

• Blood culture bottles
• conventional culturing
• endophthalmitis
• MALDI-TOF mass spectrometry

DECLARATION OF INTEREST

S. Xu, None; C. Zhou, None; P. Zhang, None; C. Feng, None; T. Zhang, None; Z. Sun, None; H. Zhuang, None; H. Chen, None; Q. Chang, None; R. Jiang, None; H. Li, None; Y. Ni, None.

Additional information

Funding

Supported by research grants from National Natural Science Foundation of China (NO.81570855); the Shanghai Three-Year Plan of the Key Subjects Construction in Public Health-Infectious Diseases and Pathogenic Microorganism (15GWZK0102).