Serratia marcescens harboring SME-4 in Brazil: A silent threat

Area of Science:

• Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Serratia marcescens exhibits intrinsic resistance to polymyxins, a critical class of last-resort antibiotics.
• The emergence of carbapenemase-producing Enterobacteriaceae (CPE) poses a significant global health threat.
• Carbapenemase genes, such as SME-4, can be acquired by intrinsically resistant bacteria, exacerbating treatment challenges.

Observation:

• This study reports the first identification of a carbapenemase-producing Serratia marcescens isolate in Brazil.
• The isolate was identified in a patient experiencing septic shock, indicating a severe clinical manifestation.
• The carbapenemase identified in the isolate was SME-4, a metallo-beta-lactamase.

Findings:

• The presence of SME-4 carbapenemase in Serratia marcescens contributes to resistance against a broad spectrum of beta-lactam antibiotics, including carbapenems.
• This finding underscores the adaptability of Serratia marcescens in acquiring novel resistance mechanisms.
• The isolation of this multidrug-resistant strain in Brazil raises concerns about its potential dissemination within healthcare settings and the community.

Implications:

• The spread of carbapenemase-producing Serratia marcescens necessitates enhanced surveillance and infection control measures in Brazil.
• Urgent development and implementation of effective treatment strategies are required to combat infections caused by such resistant pathogens.
• This case highlights the critical need for continuous monitoring of emerging antimicrobial resistance patterns globally.