Endometritis associated with Globicatella sanguinis and Staphylococcus lentus in a mare: a case report.

Introduction: Bacterial endometritis represents one of the most important reproductive diseases in mares causing considerable economic loss. Bacterial pathogens are a potential cause when a mare fails to conceive to a fertile stallion on a well-managed breeding farm on one or more cycles in the same season. Streptococcus group C and Escherichia coli are the most frequently bacterial strains associated with fertility problems. Furthermore, emerging bacterial resistance to commonly used antibiotics has been demonstrated. Here, we present a case of endometritis in a mare which was attributed to a co-infection by a strain of Globicatella sanguinis, an unusual gram-positive coccus, which is only very rarely isolated in animal clinical specimens, and a strain of Staphylococcus lentus. Materials and Methods: Cytological examination of the sample stained and examined under microscopy was performed to evaluate the presence of polymorphonuclear (PMN) cells. For the bacteriological examination the uterine swab sample was inoculated in Brain Heart infusion (BHI) medium and then, after 24 h of incubation, on different agar plates (blood agar, MacConkey agar, Mannitol Salt Agar, Sabouraud Dextrose Agar) and incubated for further 24 h at 37°C. The isolated bacteria were identified by a miniaturized panel of biochemical tests, API systems. Antimicrobial resistance testing was performed by disk diffusion method on Mueller Hinton agar plates. Results: Cytological examination showed presence of PMN and absence of bacteria. The uterine swab incubated in BHI and then streaked onto different agar plates provided microbial culture. Based on their growth capacity on the different plates and on biochemical identification, Globicatella sanguinis and Staphylococcus lentus were identified. The both isolates showed a multi-drug resistant profile, precisely they were resistant to 13/16 and 9/16 of the tested antibiotics, respectively. Ceftriaxone (2 g in 100 ml physiological solution) was administered in intrauterine infusion for 3 days after the insemination, and gentamicin (7 mg/kg) for seven day intravenously. The mare was pregnant 25 days after the ovulation. Conclusions: To our knowledge, this is the first case of Globicatella sanguinis associated with endometritis in mares. Furthermore, this strain showed an alarming antimicrobial resistance profile. However, we conclude that bacteriological results of uterine swabs obtained through enrichment culture step may substantially increase the culture sensitivity, give more trustworthy results and provide advantage to define the correct therapy.