Weissella confusa septicemia in a foal

Weissella confusa is a Gram-positive bacterium that has been identified in environmental and food samples from around the world. Rare cases of bacteremia in immunocompromised people have been reported. A 2-day-old foal was presented for weakness and suspected sepsis. Blood culture yielded pure growth of a Gram-positive coccobacillus, which was identified as W. confusa through sequencing of the 16S ribosomal DNA. Although the foal initially responded to antimicrobial therapy with ceftiofur and metronidazole, it later developed septic complications of the right tarsocrural joint and right digital flexor tendon sheath and was euthanized. Postmortem examination and histology revealed subcutaneous icterus, severe diffuse interstitial pneumonia, septic synovitis, necrotizing vasculitis with marked thrombosis and hemorrhage in the medial digital vessels of the right hind limb, and ischemic necrosis of the right hind hoof laminae. Gram-positive, coccobacilli were observed in the vascular lesion.