Meningitis in Cats: Signs, Causes, Treatments
Overview
Meningitis in cats is a serious disease that requires aggressive treatment. Fortunately, meningitis in cats is rare. But statistics are no comfort for pet parents whose cat is suffering.
Initially, the signs of cerebral meningitis in cats are vague—tiredness, loss of appetite, hiding—the same symptoms of almost every cat illness. This is why it is important to have your cat evaluated by a veterinarian. The sooner meningitis can be diagnosed and treated, the more likely a good outcome is for your cat.
What Is Feline Meningitis?
Meningitis is inflammation of the layer of protective tissue that covers the brain and spinal cord. That tissue is called the meninges. The suffix -itis means inflammation. Often if there is swelling of the meninges, there is also swelling of the brain it protects. Inflammation of the brain tissue is called encephalitis. Together, inflammation of both the brain and meninges is called meningoencephalitis. If the spinal cord tissue is also involved, it’s called meningoencephalomyelitis.
Many of the causes of feline meningitis are infectious. Therefore, cats who spend time outside are at highest risk for meningitis. Those who are unvaccinated and live outdoors are at highest risk for contagious meningitis. There are no breed or sex differences in risk, although there does appear to be a genetic predisposition for the autoimmune (non-infectious) form of the disease. Meningitis is not directly transmissible between cats, although those who share an environment are also likely to share exposures to organisms that cause meningitis.
What Causes Meningitis in Cats?
There are many infectious causes of meningitis in cats, including bacteria, viruses, fungus, parasites, tick-borne diseases, and single-celled organisms called protozoa. In cats, bacterial meningitis is more rare than the other infectious origins. Other brain disorders in cats can be caused by these same types of pathogens. Meningitis may also be caused by some types of chemicals or toxins. The final category of causes of meningitis in cats is auto-immune disease. Sometimes, despite diagnostic testing, a cause for feline meningitis cannot be determined. These cases are considered idiopathic, meaning no cause is known.
Types of Meningitis in Cats
There are several types of meningitis in cats, including:
Auto-immune: An overreaction of the immune system causes inflammation of the meninges. This type of meningitis can usually be treated with corticosteroid drugs.
Bacterial: Bacterial meningitis is more common in livestock than pets.
Fungal: Fungal meningitis can be localized to the brain and spinal cord or can be a result of disseminated infection, meaning the fungus is found all over the body.
Viral: This is the most common cause of meningitis in cats. Feline Infectious Peritonitis and Feline Leukemia Virus are both known to reach the brain and cause meningitis. Viral meningitis carries a grave prognosis—it is generally a fatal disease.
Protozoal: Protozoa are single-celled organisms. They can arrive in the meninges through the nose, ears, bloodstream, or open wounds. Protozoal meningitis can sometimes be effectively treated with antibiotics.
Parasitic: Parasites (for example roundworms, bot flies, etc.) can find their way into the meninges and cause localized inflammation and/or infection. Parasitic meningitis is typically treated with anthelmintic medications as well as antibiotics.
Idiopathic: When no cause of meningitis can be found, it is called idiopathic. Unfortunately, idiopathic meningitis has a poor prognosis.
What Are Signs of Meningitis in Cats?
The symptoms of meningitis in cats vary widely from minimal to severe, from slow onset to rapid progression, and from specifically neurologic to non-specific whole body signs.
The most common signs of meningitis are fever, neck pain, muscle spasms, and severe pain that is difficult to localize. More specific signs include a head tilt, walking in circles, and loss of balance. Other signs include lethargy, blindness, abnormal movements, paralysis, behavior changes, seizures, and coma.
The signs of meningitis depend on the location of the swelling, whether around the brain, cerebellum, spinal cord, or multiple locations. The symptoms do not differ between the causes of meningitis, which is part of what makes diagnosis difficult.
To recap, here is a list of signs of meningitis in cats:
- Fever
- Pain
- Muscle spasm
- Blindness
- Inability to walk or poor balance
- Abnormal gait
- Lethargy
- Seizures
- Abnormal body movements
- Head bobbing and other abnormal head movements
- Head tilt
- Agitation or changes in behavior
- Weakness
- Coma
Diagnosing Feline Meningitis
The diagnosis of meningitis in cats starts with a thorough history and physical exam. Bloodwork and X-rays are useful to rule out the presence of other more common illnesses and injuries. The specific tests required to diagnose meningitis are evaluation of the cerebrospinal fluid (CSF, the fluid that goes around and through the brain) and an MRI to confirm the presence of inflammation. These tests may be ordered when bloodwork and X-rays of the body appear to be normal but a cat has persistent or progressive neurologic signs.
Cat Meningitis Treatment Options
The treatment for meningitis in cats depends on the cause. Whether antibiotics, antivirals, antifungals, or antiparasitics are required is based on the results of the CSF analysis. The success of treatment depends on the cause and how quickly treatment is initiated. It can vary widely. Some cats return to normal with treatment, while other cats get no relief from treatment or may even worsen.
Auto-immune and idiopathic forms of meningitis are treated with steroid medication. All forms of meningitis in cats require supportive care: fluids, feeding assistance, and pain control to give the specific medication time to take effect. Sometimes these cats can be treated at home, but most cats with meningitis require at least some amount of hospitalization until their symptoms can be managed.
Prognosis for Cats With Meningitis
Immune-mediated, tick-borne, and protozoal forms of meningitis have the best likelihood of a positive outcome, although overall the prognosis for any type of meningitis in cats is still guarded. The other forms of meningitis, such as bacterial, fungal, and viral, carry a poor prognosis. Getting your cat into the vet at the first sign of a problem can go a long way to helping them get better.
Cost to Treat Meningitis in Cats
The cost to diagnose and treat meningitis in cats varies but it is a significant financial investment due to the cost of diagnostic testing and hospitalization. An MRI and CSF analysis can cost $3,000-$6,000. Hospitalization is in the range of $1,000-$3,000 per day. Some cats may only require a few days while other cats may require weeks in the hospital in order to adequately manage their pain.
How to Prevent Meningitis in Cats
While there is nothing a pet parent can do to prevent meningitis specifically, keeping your cat indoors and up to date on vaccines significantly reduces the risk of meningitis.