Equine myositis and septicemia caused by Acinetobacter calcoaceticus infection.

The research article discusses a case of equine myositis (muscle inflammation) and septicemia (blood infection) that was caused by an infection of Acinetobacter calcoaceticus in a mare, which ultimately led to her death.

Objective of the Research

The purpose of this study was to investigate and document the symptoms, clinical presentation, and post mortem findings on a mare afflicted with myositis and septicemia due to Acinetobacter calcoaceticus infection.

Clinical Presentation of the Equine Infection

• The infected mare presented with a variety of symptoms including ventral swelling and edema, diarrhea, listlessness, and an elevated rectal temperature.
• Despite receiving symptomatic treatment for 2 days, the mare’s condition deteriorated, leading to death on the 3rd day.

Post Mortem Findings

• Upon necropsy, the mare was found to have myositis, enteritis, typhlitis, colitis, and hepatitis. These are conditions involving inflammation and infection in various organs and tissues.
• Moderate enlargement of lymph nodes throughout the body was also observed. This typically indicates an infection or disease.
• Visibly, the muscles had edema, scarring, petechiae (small, red or purple spots caused by minor bleeding from broken capillary blood vessels) and occasional exxhymosis (a discoloration of the skin resulting from bleeding underneath).
• The inflammation in the intestines was catarrhal, manifested by the excessive mucus and moderate hyperemia (increased blood flow).
• Along with inflammation, the caecum and colon had bleeding.
• The liver was swollen and exhibited a diffused mottled pale and red pattern, hinting at liver damage.

Microscopic Findings

• Examining skeletal muscle microscopically, petechiation, necrosis, scarring, and edema were observed.
• The heart muscle was also scarred and necrotic (dead tissue), although edema was less noticeable.
• Periacinal necrosis, or death of the cells around the central veins of the liver, was identified.

Bacteriological Findings

• The bacterium, Acinetobacter calcoaceticus, was isolated from both the heart tissue (myocardium) and the liver, confirming its role in the disease process.