Feline Meningitis Study Guide

Overview and Clinical Importance

Meningitis refers to inflammation of the meninges, the protective membranes that surround the brain and spinal cord. When inflammation extends to include the brain parenchyma, it is termed meningoencephalitis, and when the spinal cord is also involved, it is called meningoencephalomyelitis. In cats, meningitis is more common than in dogs and represents a significant neurological emergency requiring rapid diagnosis and treatment.

The meninges consist of three layers: the dura mater (outermost, tough fibrous layer), the arachnoid mater (middle web-like layer), and the pia mater (innermost layer closely adhering to the CNS). The subarachnoid space between the arachnoid and pia mater contains cerebrospinal fluid (CSF), which provides cushioning, nutrient delivery, and waste removal for the CNS.

Etiology and Pathophysiology

In cats, meningitis most commonly results from infectious causes, with feline infectious peritonitis (FIP) being the most prevalent etiology. Unlike dogs, where steroid-responsive meningitis-arteritis (SRMA) is common, immune-mediated meningitis is less well-characterized in cats.