Meningitis in Dogs - Symptoms, Types, Diagnosis, and Treatment

Animals, just like us, are exposed to a wide range of conditions throughout their lives. Many of these are shared between both species, as is the case with meningitis.

It appears unexpectedly and causes serious health problems in our dogs. Although meningitis is a potentially fatal disease, many dogs manage to recover if it's caught in time and properly treated.

That's why it's important to know all the details about this disease. That way, if you ever notice any of these symptoms in your own dog, you'll be able to act in time.

Types of meningitis

Canine meningitis is a neurological disease that causes inflammation of the meninges, three protective membranes surrounding the central nervous system (brain and spinal cord), known as the dura mater, arachnoid, and pia mater. The causes of this condition can vary widely, and depending on this, several types of meningitis are distinguished.

One of the best-known is immune-mediated autoimmune meningitis, which tends to be diagnosed more often in puppies and young dogs. In these cases, the disease is aseptic — that is, it's linked to a disruption in the immune system itself, not to an infection.

There's also infectious meningitis, caused by various infectious agents.

• Bacterial: resulting either from direct spread of a process not originating in the CNS itself (inner ear infection, sinusitis, migration of foreign objects around the eyes, nose, or throat, discospondylitis...) or from direct damage to the CNS (bites or head trauma). Bacterial meningitis tends to occur more often in puppies.
• Viral: the most common in dogs is caused by the canine distemper virus, accompanied by a multisystem clinical picture (digestive, respiratory, dermatological, and neurological). Cases caused by parvovirus have also been described, but are less common. Lastly, tick-borne Central European encephalitis is on the rise, and tends to be asymptomatic.
• Fungal: very uncommon.
• Protozoal: most often caused by Toxoplasma gondii and Neospora caninum, though sometimes also by Leishmania.

Lastly, there are others of genetic origin, such as Greyhound meningoencephalitis, which affects Greyhounds, and many others of unknown origin (idiopathic), such as granulomatous meningitis, typical in Poodles, Toy breeds, and Terriers, or eosinophilic meningitis, characteristic of the Rottweiler, Labrador Retriever, Belgian Tervuren Shepherd, and Maremma Sheepdog, among others.

Inflammation of the meninges is usually accompanied by inflammation of the brain, in which case we speak of meningoencephalitis. If it's associated with inflammation of the central nervous system's arteries, it's called meningoarteritis, which is the most common variant in large dog breeds (Boxer, Bernese Mountain Dog, and Beagle).

Either way, it will be the vet who, through various tests and analyses, can give an accurate diagnosis. MRIs, ultrasounds, and spinal taps to draw and examine cerebrospinal fluid tend to be the key procedures for determining what type of meningitis a dog has.

Main symptoms of canine meningitis

Although symptoms can vary widely depending on the type of meningitis contracted and the dog's health and age, these are the most common symptoms of this disease:

• Intense neck pain.
• Total or partial loss of appetite, vomiting, dizziness.
• High fever.
• Increased sensitivity to stimuli (hyperesthesia).
• Altered mental state.
• Body stiffness, ataxia (abnormal gait), and seizures.
• Blindness and/or other cranial nerve abnormalities.

If any one or more of these symptoms is present, it's best to always see a vet so they can run the appropriate tests and reach a diagnosis.

Aftereffects of meningitis

In treating meningitis, timing is key to stopping the disease's progression and fully overcoming it. If not caught early, the dog could die or suffer very serious health complications.

One of the most dangerous is hydrocephalus, a buildup of cerebrospinal fluid in the brain. That's why it's very important to take your dog to the vet immediately at any warning sign.

In some cases, dogs that do recover from meningitis will need lifelong physical therapy and medical treatment.

The most common aftereffects are:

1. Seizures, due to the brain dysfunction caused by the meningitis.
2. Paresis. That is, partial loss of voluntary movement, or mild to partial paralysis, generally described as muscle weakness.
3. Paralysis. This prevents the dog from moving, keeping their balance, and maintaining posture as they normally would.

As you can see, most aftereffects result from the damage the inflammation causes to the dog's brain and nervous system. Once the emergency has passed, your vet will advise you on how to manage them and the best path to take to minimize them as much as possible.

Can canine meningitis spread to humans?

A common question, once a meningitis diagnosis is confirmed in our dog, is: "Can this disease spread to humans?" We can certainly get meningitis too, but it's important to know that the canine variant is different from ours.

So, it can't spread from dog to human, or from human to dog — it isn't a zoonosis. That said, if the meningitis was caused by parasites, it's never a bad idea to take some precautions and all necessary measures to avoid exposure ourselves.

Treatments for meningitis

As for treating meningitis in dogs, there are several options. Depending on the type of meningitis diagnosed, one treatment or another will be applied. Steroids are usually prescribed to reduce brain inflammation and prevent aftereffects. It's important to note that corticosteroids need to be tapered off slowly and gradually over several months to avoid relapses.

Even so, some animals can relapse during this process. When the meningitis is caused by infectious agents such as bacteria, antibiotics are given intravenously. Other symptoms, such as seizures, are also treated with specific medications that help control them, such as anti-epileptic drugs.

If it's a severe case, the dog will be hospitalized and monitored by a specialist until they're past the crisis. Keep in mind that the prognosis for meningitis varies widely, depending on both the cause and the animal's physical condition. Viral meningitis is indeed usually the hardest to manage. However, there are many cases where the dog does respond well to treatment and, with proper care, can go back to living a normal life.

So if you're at this point, don't lose hope, and don't skip your dog's follow-up check-ups to prevent relapses. Remember: never consider the battle lost, but don't forget the fight either after winning just one round.