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[Occurrence of 16s rRNA methylase ArmA producing Enterobacteriaceae in a general hospital in Warsaw, Poland]
Katarzyna Piekarska1, Katarzyna Zacharczuk, Elzbieta Bareja
1Zakład Bakteriologii Narodowego Instytutu Zdrowia Publicznego-Państwowego Zakładu Higieny.
Abstract:
Resistance to gentamicin, amikacin and kanamycin was screened in 270 clinical isolates of Enterobacteriaceae originated from April 19 to May 19, 2010 in a regular hospital in Warsaw, Poland. Most of the isolated bacteria were considered pathogenic. Nineteen isolates (7%) were simultaneously resistant to two or three of the tested aminoglycosides. MICs of the three aminoglycosides ranged form 128 to 1024 mcg/ml for six isolates. These isolates were suspected to produce 16S rRNA methylase. Genes encoding for three methylases reported in Europe: ArmA, RmtB and RmtC were searched by PCR. The armA gene was detected in all of the six isolates. This group encompassed Enterobacter cloacae (n=4), Klebsiella pneumoniae (n=1) and Proteus mirabilis (n=1). Five isolates of this group carried the bla(CAX-M) gene for CTX-M type ESBL. The remaining isolate E. cloacae DM0340 was ESBL negative and lacked bla(CRX-M) that may suggest an altered genetic environment of the armA gene in this isolate. Our results showed that 2.2% of the tested isolates produced 16S rRNA methylase ArmA. This finding may argue for a high incidence of ArmA producing Enterobacteriaceae in Poland when compared to reports from other European countries.
Insights
A study found the ArmA gene, responsible for aminoglycoside resistance, in 2.2% of Enterobacteriaceae clinical isolates in Poland. This indicates a potentially high incidence of this resistance mechanism in the region.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Context:
- Aminoglycoside resistance is a growing global health concern.
- Enterobacteriaceae are common causes of hospital-acquired infections.
- The prevalence of 16S rRNA methylase-producing Enterobacteriaceae varies geographically.
Purpose:
- To screen clinical Enterobacteriaceae isolates for resistance to gentamicin, amikacin, and kanamycin.
- To identify the presence of 16S rRNA methylase genes, specifically ArmA, RmtB, and RmtC.
- To investigate the co-occurrence of the ArmA gene with extended-spectrum beta-lactamase (ESBL) genes.
Summary:
- 270 clinical Enterobacteriaceae isolates from Warsaw, Poland, were tested for aminoglycoside resistance.
- Six isolates exhibited high-level resistance and were suspected of producing 16S rRNA methylase.
- PCR confirmed the presence of the ArmA gene in all six isolates, with four co-harboring bla(CAX-M) for CTX-M ESBL.
Impact:
- This study identified ArmA-producing Enterobacteriaceae in 2.2% of isolates, suggesting a high incidence in Poland compared to other European countries.
- The findings highlight the need for enhanced surveillance of aminoglycoside resistance mechanisms in clinical settings.
- Understanding the genetic basis of resistance, including the association with ESBLs, is crucial for effective antimicrobial stewardship.
