Melioidosis with acute meningoencephalomyelitis in a horse.

The study discusses a case of acute meningoencephalomyelitis in a horse, caused by the bacterial infection Pseudomonas pseudomallei, showing symptoms like difficulty standing, spoilage, facial paralysis and involuntary eye movements, and leading to violent resistance.

Case Description

• The study revolves around a case of acute meningoencephalomyelitis, a neurological condition characterised by severe inflammation of the brain, spinal cord, and meninges (the protective membranes that surround these structures) in a horse.
• This condition was caused by an infection with Pseudomonas pseudomallei, a type of bacteria that can cause a range of diseases in humans and animals, including melioidosis.
• The infected horse displayed clinical symptoms such as inability to stand, opisthotonus (a condition where the horse’s head and tail are pulled towards its back), facial paralysis, and nystagmus (involuntary eye movements).
• These symptoms rapidly progressed to violent struggling, indicating the severity of the condition.

Examination Findings

• Gross examination indicated a softening (or malacia) and haemorrhage (bleeding) in the medulla oblongata (a part of the brainstem) and the adjoining spinal cord.
• Microscopic evaluation showed disseminated focal neutrophilic accumulations in affected areas. Neutrophilic accumulations are collections of neutrophils, a type of white blood cell, which serve as a response to infection or inflammation.
• The affected areas also showed perivascular cuffing with mononuclear cells (a single nucleus) and lymphocytes. Perivascular cuffing refers to the accumulation of immune cells around the blood vessels, which often occurs during inflammation or infection within the central nervous system.
• A pronounced swelling (or edema) was also observed, which is a common reaction to injury or inflammation.
• The examination also revealed the presence of intracellular bacteria identified in sections stained by the Giemsa method, a stain commonly used to identify bacteria and other microbial organisms, indicating the presence of Pseudomonas pseudomallei.