ESBL-producing Enterobacteriaceae from non-human sources (poultry and swine) in Portugal

Abstract number: 1733_533

Machado E., Coque T., Cantón R., Baquero F., Silva J., Sousa J.C., Peixe L.

Objectives: To investigate the occurrence and diversity of ESBL-producing Enterobacteriaceae among healthy animals and raw poultry meat samples from Portugal.

Methods: We studied (i) 35 faeces samples from healthy swines (HS) in 1998 and 2004, (ii) 20 samples from uncooked poultry carcasses (PM) of two poultry retail markets (2003), and (iii) 20 faecal samples from healthy poultry (HP) in 2004 (n = 20). HS and HP were from distant geographic farms. Animals were not exposed to antibiotics in the 3 months preceding sample recovery. Samples were plated on MacConkey agar with ceftazidime (1 mg/L) or cefotaxime (1 mg/L). ESBL characterisation was accomplished by double disk diffusion, PCR, and sequencing. Bacterial identification was performed using API ID 32GN and antibiotic susceptibility tested by the disk diffusion method (CLSI). Clonal relatedness was established by RAPD and E. coli phylogenetic groups were identified by a multiplex PCR. Conjugation experiments were performed as described.

Results: ESBL were identified in PM (60%, 12/20), HS (5.7%, 2/35) and HP (10%, 2/20). ESBL-producing isolates were identified as C. freundii (2HS), E. coli (n = 12; 2HP, 10 PM) and K. pneumoniae (n = 4; 4PM), and ESBLs as TEM-52 (n = 12), SHV-2 (n = 3), SHV-12 (n = 2), and CTX-M-1 (n = 1). TEM-52 was found among E. coli. SHV-2 only detected in K. pneumoniae, SHV-12 only observed among C. freundii isolates and CTX-M-1 in one E. coli. Isolates showed decreased susceptibility patterns to other antimicrobial classes. Most bla genes were transferred by conjugation. RAPD analysis revealed that 2 TEM-52-producing E. coli from PM, 2 TEM-52-producing E. coli from HP, 2 SHV-2-producing K. pneumoniae and 2 SHV-12-producing C. freundii were clonally related (4 distinct RAPD-types). The remaining isolates showed unique RAPD patterns. These isolates and ESBL-producing clinical isolates spreading in Portuguese hospitals during 2003 and 2004 were clonally unrelated. E. coli phylogenetic group A was predominant (58.3%). Less represented phylogroups were D (33.3%) or B1 (8.3%).

Conclusions: This work constitutes the first report of some ESBLs from Enterobacteriaceae from livestock. The frequent presence of ESBL-producing Enterobacteriaceae in poultry meat in Portugal highlights the risk of transmission to humans via food chain. Horizontal gene transfer could be responsible for ESBL dissemination in our country.

Session Details

Date: 31/03/2007
Time: 00:00-00:00
Session name: European Society of Clinical Microbiology and Infectious Diseases
Location: ICC, Munich, Germany
Presentation type:
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