Sepsis in Critically Ill Patients: Epidemiology, Risk Factors, and Role of Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry for Identification of Sepsis-Causing Organisms

Background Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) is a rapid mass spectrometry technology for species identification. It is a useful, fast, and accurate tool for routine laboratory analysis. This study aimed to investigate the epidemiology of sepsis-causing organisms in patients admitted to tertiary-level intensive care units (ICU), the role of MALDI-TOF MS in species identification, and patients’ clinical outcomes. Methodology A prospective observational study was performed in a tertiary-level ICU for one year. The first blood, urine, and endotracheal (ET) aspirate samples were sent before starting antibiotics. We received the antibiotic sensitivity report within 48 hours or earlier using MALDI-TOF MS. Treatment was modified based on MALDI-TOF MS reports. Response to treatment was monitored, and clinical outcomes were noted based on ICU stay. Patients were followed up until discharge, shifting to referring parent unit, or death. Results This study included 200 patients admitted to ICUs who at the time of admission did not have a fever. The most common organisms were Acinetobacter baumannii, Klebsiella pneumonia, and Escherichia coli in ET aspirates; Candida albicans and Enterococcus faecium in urine; and Pseudomonas aeruginosa, K. pneumonia, and A. baumaniiin blood. Of the 200 patients, 130 (65%) shifted to the parent unit ward, and 70 (35%) patients died, with an ICU stay of 12.89 ± 6.51 days. There was no significant difference in mortality when organisms grew from either ET or urine compared with sterile samples. If organisms resistant to all primary antibiotics grew from ET, mortality was 60.6%. Mortality was 56.8% if isolates were in the blood. Conclusions Early MALDI-TOF MS-based species identification and appropriate antibiotics initiation play a key role in the treatment and care for critically ill patients with sepsis. MALDI-TOF MS has the potential to significantly aid sepsis management.