Definition
Meningitis is a condition that occurs in cats when one or more of the three tissue layers that surround and protect the brain and spinal cord, known as the “meninges,” become inflamed and/or infected.
How Meningitis Affects Cats
Meningitis is not a disease. It is a very serious and painful pathological condition of inflammation of delicate tissues surrounding the brain. This typically leads to inflammation of the brain and/or spinal cord, causing direct neurological deficits. It is more common in companion dogs than in domestic cats. However, cats of any age, breed or gender can be equally affected, although newborns and immunocompromised animals are especially at risk. Affected animals are almost always systemically ill. They develop a high fever, a stiff neck and awkward gait, painful muscle spasms in the back, limb rigidity and extreme sensitivity to touch and temperature. They progressively become lethargic, anorexic and nauseous and frequently vomit. Advanced meningitis can cause profound depression, blindness, progressive paralysis, seizures, confusion, agitation, incoordination (ataxia) and/or aggression.
Causes of Feline Meningitis
Meningitis can be caused by anything that triggers the inflammatory cascade in the tissues of the meninges. This can be viral, protozoal, bacterial, fungal, rickettsial or parasitic. Chemical toxins (lead, arsenic, etc.) have been implicated as well. Even metastatic cancer cells reportedly can cause or contribute to meningitis. Viral feline infectious peritonitis infections and blood parasites spread through ticks, such as Rocky Mountain spotted fever and ehrlichiosis, may also cause feline meningitis. Meningitis is an extremely serious condition that can be fatal.
Preventing Meningitis in Cats
There is no way to prevent meningitis, other than preventing the underlying cause of the inflammation which most frequently is bacterial or viral. As with most illnesses, a high-quality diet, free access to fresh water, good housing conditions and regular veterinary check-ups will support a healthy immune system in domestic cats.
Special Notes
Meningitis can be difficult to diagnose and to treat. Meningitis is often diagnosed through spinal fluid taps, although sampling the cerebrospinal fluid in affected animals is contraindicated if there are signs suggestive of high intracranial pressure. Blood tests and blood cultures may also be useful to eliminate underlying systemic causes of the clinical signs. The long-term prognosis for cats with meningitis is generally guarded to poor. Part of the difficulty with diagnosing and treating meningitis in cats is that it the condition is so often caused by another serious underlying condition which must be independently addressed. The “general” meningitis treatment protocol is to use immunosuppressive drugs, such as steroids, and broad-spectrum antibiotics that will penetrate the blood-brain barrier to reduce the effects of swelling and eliminate any contributing bacterial infection. Unfortunately, these treatments are often of little help to affected cats.