Bacteraemia caused by ESBL-producing Salmonella enterica serovar. virchow 6.7:r:1,2 – a cause for concern

Abstract number: 902_p769

Guleri A.


Antibiotic resistance in Salmonellae is now common. In developed countries such strains are largely zoonotic and acquire resistance in the animal host before transmission to humans in food. We present our first case of bacteraemic illness with multi-resistant, extended spectrum beta lactamase (ESBL) producing non-typhoidal Salmonella.

Case summary:

A 34-year-old male, with a history of recent foreign travel was admitted to hospital with a 7–10 day history of gastrointestinal symptoms/fever. On admission he was febrile and splenomegaly was detected. Physical examination was otherwise normal. Biochemistry revealed mildly deranged liver function. Salmonella enterica serovar. virchow 6.7:r:1,2 was isolated from blood culture. It was sensitive in vitro (NCCLS disk test) to ciprofloxacin and gentamicin but resistant to ampicillin, cefuroxime, cefotaxime, ceftriaxone, ceftazidime, co-trimoxazole, nalidixic acid and streptomycin. MIC of ciprofloxacin was 0.094 mg/L. Antibiotic treatment was with ciprofloxacin, to which he responded well.

ESBL detection:

The isolate was identified as Salmonella enterica serovar. virchow 6.7:r:1,2 [API 20 identification system (bioMérieux), serogrouping, serotyping and phagetyping]. The isolate, resistant in vitro (NCCLS) to cefotaxime and ceftazidime, was tested for extended-spectrum beta lactamase/AmpC production by phenotypic methods. AB Biodisk ESBL E–tests (cefepime, ceftazidime and cefotaxime, each ± clavulanic acid) and Oxoid ESBL combination disks (cefpodoxime, ceftazidime, cefotaxime and cefpirome, each ± clavulanic acid) and cefoxitin alone were used based on modified NCCLS/manufacturer's guidelines. The isolate tested positive for ESBL production by both ESBL E-tests and combination disks. Molecular typing of the ESBL is awaited.


Invasive infection with Salmonella virchow is uncommon. The source of infection in this case appears to have been undercooked chicken. The emergence of resistance to antimicrobial agents within the salmonellae is a worldwide problem that has been associated with the use of antibiotics in livestock. Invasive infection with S. virchow, resistant to broad-spectrum beta-lactams, is a cause for concern. If antimicrobial therapy is indicated for travellers with a history of recent foreign travel, physicians should be aware of the possibility of treatment failures and in such cases MICs of third-generation cephalosporins and ciprofloxacin should be determined.


Session Details

Date: 01/08/2007
Time: 00:00-00:00
Session name: XXIst ISTH Congress
Location: Oxford, UK
Presentation type:
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