First Report of DHA-1 Producing Enterobacter cloacae Complex Isolate in Bulgaria

• Published in: Folia medica (Plovdiv) Vol. 61; no. 3; pp. 458 - 461
• Main Authors: Dimitrova, Dobromira I., Markovska, Rumyana D., Stoeva, Temenuga J., Stankova, Petya B., Georgieva, Lyudmila B., Mihova, Kalina I., Kaneva, Radka P., Mitov, Ivan G.
• Format: Journal Article
• Language: English
• Published: Plovdiv MEDICAL UNIVERSITY- PLOVDIV 30-09-2019; Pensoft Publishers
• Subjects: AmpC; Antibiotics; Antimicrobial agents; Bulgaria; DHA-1; E coli; Enterobacter cloacae; Enzymes; Experiments; Genes; Hospitalization; Laboratories; Nosocomial infections; Iran; Bulgaria; China; Japan
• ISSN: 0204-8043; 1314-2143
• DOI: 10.3897/folmed.61.e39349

The aim
of the present study was to reveal the characteristics of an
Enterobacter cloacae
complex isolate producing DHA-1 AmpC enzyme recovered from a patient hospitalized in St Marina Hospital, Varna.
Materials and methods:
Susceptibility testing, conjugation experiments, isoelectric focusing, PCR and sequencing were carrying out.
Results:
Of 176
Enterobacter
spp. isolates only one isolate was positive for
bla
DHA. The sequencing revealed the presence of
bla
DHA-1 and
bla
CTX-M-3. The antimicrobial susceptibility testing showed higher resistance rates to almost all beta-lactams (ceftazidime, cefotaxime, cefepime, amoxicillinclavulanic acid, piperacillin/tazobactam), tobramycin, gentamycin, trimethoprim/sulphomethoxazole and quinolones (ciprofloxacin and levofloxacin). The isolate was susceptible to imipenem, meropenem and amikacin. The isoelectric focusing showed a band at pI 5.4 without ceftazidime and cefotaxime activity; a band at pI 7.8 with cefoxitin activity and another - with pI 8.4 with cefotaxime activity. Conjugation experiments were successful only for
bla
CTX-M-3 carrying determinants.
Conclusions:
To the best of our knowledge this is the first report of DHA-1 producing isolate in Bulgaria. The emergence of DHA-1 producing
E. cloacae
complex demonstrates the possibility for further dissemination of the gene encoding this enzyme. Infectious control measures are needed for the prevention of this phenomenon.