The causal relationship between O2:K7:H6 extra-intestinal pathogenic Escherichia coli (ExPEC) and native valve endocarditis: a case report

Background

Native valves infective endocarditis due to Escherichia coli is still a rare disease and a particular virulence of some E.coli isolate may be suspected.

Case presentation

A 79-year-old woman presented during the post-operative period of an orthopedic surgery a urinary tract infection following obstructive ureteral lithiasis. E. coli was isolated from a pure culture of urine and blood sampled simultaneously. After evidence of sustained E.coli septicemia, further investigations revealed acute cholecystitis with the same micro-organism in biliary drainage and a native valve mitral endocarditis. E.coli was identified as O2:K7:H6, phylogenetic group B2, ST141, and presented several putative and proven virulence genes. The present isolate can be classified as both extra-intestinal pathogenic E.coli (ExPEC_JJ) and uropathogenic E. coli (UPEC_HM).

Conclusions

The relationship between the virulent factors present in ExPEC strains and some serotypes of E. coli that could facilitate the adherence to cardiac valves warrants further investigation.

Inhibitory effect of Azone (1-dodecylazacycloheptan-2-one) on herpes simplex viruses. In vivo and in vitro studies

Enhanced activity of antiviral agents, when mixed with a penetration enhancer like Azone (1-dodecylazacycloheptan-2-one) in topical preparations, is well-recognized. These studies were undertaken to investigate whether Azone, per se, has any activity against herpes simplex (HSV) type 1 and type 2 viruses. When HSV-1 and HSV-2 were mixed with 5, 10 and 20% Azone, there was a 1-4.5 log10 decrease in virus titers. The efficacy of 5 and 10% Azone applied topically was evaluated during the treatment of HSV-1 cutaneous infections in guinea pigs. HSV-1 infection was produced by intradermally inoculating guinea pigs with 10(7.7) HSV-1/ml. The mean number of lesions per site was reduced by more than 50% in Azone-treated sites as compared to no treatment (control) sites (p less than 0.01). Similarly, the surface area of each lesion in the Azone-treated sites was only 40% of that seen in control sites (p less than 0.001). More than 80% of the lesions on Azone-treated sites healed by day 4 as compared to only 3% on control sites (p less than 0.001). These data indicate that Azone, a lipophilic chemical, may have antiviral properties when used topically.