Multidrug resistant surgical site infection following laparotomy in horses

Post-operative surgical site infection (SSI) is a significant complication in equine surgery. SSI of the abdominal incision has been reported in 10-37% of horses undergoing emergency exploratory laparotomy for the treatment of acute colic. The development of any infection is dependent on the quantity of pathogens contaminating the tissues, the virulence of the pathogen and innate host resistance. However, several risk factors for incisional SSI have been identified and include pre-, intra-, and post operative factors. SSI caused by bacteria resistant to multiple classes of antimicrobials is a common cause of post operative morbidity and can cause considerable complications during hospitalization, such as protracted hospitalization, delayed return to function and increased client costs, together with an increased risk of incisional hernia formation and fatal evisceration. Common bacterial isolates from laparotomy incisions include Staphylococcus spp., β-haemolytic Streptococcus, Pseudomonas spp. and Escherichia coli. Infections involving multidrug resistant pathogens can make treatment quite challenging. The aim of this report is to describe a case of surgical site infection following laparotomy and caused by a multidrug resistant Escherichia coli in a 13-years-old horse successfully treated with local intradermal injections of amikacin and photobiomodulation (PMB) techniques.