Five Genetic Diseases of Cavalier King Charles Spaniels
Also called "Love Sponges", these dogs will steal your heart. Unfortunately, their tendency to develop heart and neurologic problems are often enough to scare people off from adopting these adorable, playful, dogs. While there are definitely more than five inherited disorders in the breed, this is the list of the most common I see in practice.
- Mitral Valve Disease - (MVD) - This heart disease is the leading cause of death in cavalier King Charles spaniels. Studies have shown this to affect over half of dogs over five years of age and nearly all cavaliers by age ten. It affects this breed twenty times more than other breeds. The disease causes the mitral valve on the left side of the heart to degenerate, resulting in blood flowing backward from the atrium to the ventricle. As the heart muscle weakens, the dogs eventually develop congestive heart failure. Symptoms of the disease include exercise intolerance, rapid shallow respiration, coughing, and fainting. Late stage disease symptoms include loss of body muscle mass, loss of appetite, along with abdominal fluid and swelling. The disease can rapidly progress, resulting in death in as little as one to three years after diagnosis. Suspicion of disease begins when your veterinarian hears a murmur when listening with the stethoscope. Diagnosis is made by radiograph and echocardiogram (ultrasound). Treatment includes a long list of medications and supplements, along with diet to support heart function. Pimobendin (Vetmedin) has greatly extended the lives of these dogs in recent years. Owners should monitor resting respiratory rate at home, which should remain below 30 breaths per minute.
- Giant Platelet disorder - Platelets are cells in the blood that help blood to clot. Platelet counts are included when a CBC, or complete blood count, is run on a blood sample. Many veterinarians are not familiar with this disorder and will treat these dogs as having an autoimmune thrombocytopenia, which is not needed and is very dangerous for the dog. When observed under the microscope, the platelets will be much larger than normal platelets. While a typical platelet count might be 250,000 to 400,000, cavaliers may have giant platelets with counts of 35,000 to 80,000. This is normal for this breed! Over half of cavaliers have Giant Platelet syndrome.
- Syringomyelia (SM) and Chiari-Like Malformation (CM) - Both of these neurologic diseases are common in this breed, affecting more than 50% and 95% of cavaliers, respectively. The shape of the skull contributes to pain and pressure in the spinal cord in the neck, along with a build-up of cerebrospinal fluid in the spinal cord. Symptoms of disease may include crying out in pain when moving or lifted, hesitation or refusal to climb up or down stairs, phantom scratching, head shaking, head rubbing, paw licking, anal area pain and scooting, reluctance to exercise, weakness, wobbly gait, and fly biting. Because many symptoms are similar to allergy symptoms, many dogs are tested and treated erroneously for allergies. The disease is progressive; symptoms worsen with age and may progress to scoliosis and paralysis. Symptoms rarely show before six months of age; some dogs may have the disease and show no symptoms. These dogs should be walked using a harness rather than a collar. The disease is diagnosed with MRI, but may be suspected based on symptoms. Veterinarians unfamiliar with the disease may treat for allergies, ear infections, anal gland disease, or seizures. Treatment of SM and CM focuses on pain relief. Gabapentin is generally the first drug prescribed. Pregabalin is used if gabapentin is no longer effective. Omeprazole or cimetidine may be used to decrease cerebrospinal fluid pressure. Wu Ling San is a natural diuretic that may help relieve pressure. CBD oil has proven to be very effective for many dogs. Acupuncture and cold laser therapy may reduce pain. Steroids should be used as a last resort. Surgery may be an option for some severely affected dogs.
- Patellar Luxation - This disease affects up to 20% of cavaliers. The patella is the knee cap and is found on the stifle, or hind limb knee joint. The bone should normally glide up and down between two ridges on the lower end of the femur bone when the leg is flexed and extended. Genetic predisposition to a shallow groove, weak ligaments, and misalignment of muscles can cause the patella to pop out of the groove, usually toward the inside of the leg. When the patella remains in the incorrect position, pain, degenerative joint disease, and bowing of the legs will occur. Diagnosis is made on palpation by the veterinarian and may be verified with radiographs. Dogs with mild luxations may be treated with NSAIDs (nonsteroidal anti-inflammatory medications), cold laser therapy, acupuncture, physical therapy, CBD oil and joint supplements.
- Primary secretory otitis media (PSOM) - This disorder is also known as "glue ear" and affects up to 30% of cavaliers. A very thick mucous plug fills the inner ear behind the ear drum, causing it to bulge. The disorder can occur at any age. Symptoms may include excessive yawning, crying out in pain, guarding of the head and neck, head tilt, head rubbing, crying out in pain, wobbly gait, drooping ear or lip, inability to blink an eye, rapid eyeball movement, facial paralysis or nerve palsy, drooling, vestibular disease, some loss of hearing, seizures, and fatigue. Affected dogs will scratch at the affected ear(s), which makes diagnosis difficult, as symptoms are similar to SM and CM. Diagnosis is made with MRI or CT scan. Treatment involves surgery to open the ear drum. Tubes may be inserted to allow the mucous to drain. Severely affected dogs may need ear canal ablation (removal).