Cerebellar peduncle abscess secondary to disseminated strangles in a six-week-old miniature foal

During a strangles outbreak within a herd of minature horses, a six week old foal developed acute onset clinical signs of sepsis and neurological deficits. The foal was euthanized and submitted for post-mortem at the Animal Health Laboratories, Guelph Ontario. Gross post-mortem examination noted severe bronchopneumonia, hypopyon of the right eye and a singular cerebellar peduncle abscess. Culture of the lungs and cerebellum produced a pure growth of Streptococcus equi ssp. equi. Streptococcus equi ssp. equi, the causative agent of equine strangles, produces an acute pyrexia, purulent lymphadenopathy of submandibular and retropharyngeal lymph nodes. Commonly, lymph node abscesses rupture and resolve without complication. Rarely, complications may include: dissemination of the bacteria with diffuse abscess formation, immune mediated disease (purpura haemorrhagica), rarely abscess formation within the central nervous system (CNS) can occur. These can be managed medically with appropriate antibiotics and drugs to reduce intra-cranial pressure, however surgical drainage and debulking of the abscess has been attempted successfully in a few cases.