A case of NDM-1-producing Acinetobacter baumannii transferred from India to Japan

Area of Science:

• Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• The emergence of multidrug-resistant organisms (MDROs) poses a significant global health threat.
• Acquired carbapenemases, such as New Delhi metallo-beta-lactamase 1 (NDM-1), are a major mechanism of resistance in Gram-negative bacteria.
• International travel and medical tourism facilitate the global dissemination of MDROs.

Observation:

• A 52-year-old Japanese businessman, returning from India, presented with massive cerebral bleeding and was found to have Acinetobacter baumannii in his sputum.
• The isolated A. baumannii strain exhibited resistance to multiple antibiotics, including carbapenems (imipenem, meropenem), fluoroquinolones (ciprofloxacin), and aminoglycosides (amikacin).
• Molecular analysis confirmed the presence of both blaNDM-1 and blaOXA-23 genes in the A. baumannii isolate.

Findings:

• This case represents the first documented instance of NDM-1-producing Acinetobacter baumannii identified in a clinical specimen in Japan.
• The minimum inhibitory concentrations (MICs) indicated high-level resistance to common antibiotics, with susceptibility only to colistin (<1 μg/ml).
• The presence of NDM-1, a carbapenemase rarely seen in Japan, underscores the potential for importation of highly resistant pathogens.

Implications:

• This case highlights the ease with which NDM-1-producing bacteria can be introduced into countries with low prevalence, such as Japan.
• International medical care and travel necessitate enhanced surveillance and infection control measures to prevent the spread of MDROs.
• The findings emphasize the urgent need for global collaboration in combating the spread of antimicrobial resistance.