The first time their three-year-old Akita plopped down on the sidewalk during the nightly family walk, Erin and Scott weren’t too concerned. They assumed the pooch had just had a bit too much excitement with the kids that afternoon. However, after the dog did the same thing four nights in a row, they took him to the vet. The diagnosis was myasthenia gravis.
What is myasthenia gravis in dogs?
Many people have read about this condition in human beings and are surprised to learn it can strike dogs as well. According to PetPlace.com, it’s a disorder marked by muscular weakness aggravated by the affected dog’s activity but relieved by rest.
The disease develops when specific canine nerve receptors can’t function properly. Vetinto reports that this failure interferes with the stimulus for muscles to contract. The dog then has a weak appearance.
Myasthenia gravis is considered congenital in some breeds. Among them are Jack Russell terriers, Springer spaniels and smooth fox terriers. Other breeds at elevated risk include the Akita, Scottish terrier, Chihuahua and German shorthaired pointer.
The condition seldom strikes dogs less than a year old. The age peaks for occurrence appear to be between 2 and 3 years old and between 9 and 10.
About 75 percent of human beings with myasthenia gravis suffer from an abnormality of the thymus gland. Dogs also have thymus abnormalities.
Signs and symptoms of canine myasthenia gravis
The primary characteristic of this disorder is weakness. It typically affects the esophagus, making it hard for the dog to eat and swallow.
Owners frequently note that the dog’s muscle weakness gets worse with any exercise but improves during resting periods. Many dogs suffer from regurgitation pneumonia marked by coughing and fever.
Diagnosis and treatment
Whenever a veterinarian suspects that a dog might be suffering from myasthenia gravis, chest X-rays are a standard practice to evaluate the esophagus. A vet can presumptively diagnose the illness by injecting edrophonium hydrochloride. This is known as the Tensilon test. The muscle strength of a myasthenia gravis dog normally shows an immediate but short improvement after the injection.
A vet might also order an anti-acetylcholine receptor antibody test at the lab or use electromyography, which is used in human beings during biofeedback treatment.
Depending on the dog’s condition, a vet might choose one or more treatments for myasthenia gravis. Among them are anticholinesterase drugs and medications that suppress the pet’s immune system.
Plasmapheresis is a technique to collect and separate various products from the dog’s blood. The blood cells are returned to the dog along with either plasma from a normal dog or a plasma substitute. This removes the antibodies blocking nerve impulse transmission to muscles.
A surgical option is removal of the thymus gland, though this often results in a poor outcome. Some dogs require elevated feedings or the placement of a gastrostomy tube. The esophagus of one of these dogs contracts poorly. As a result, most of them require a gruel feeding at an elevated height, then an elevation of their heads for 10 to 15 minutes to help food reach their stomachs. If a dog continues to regurgitate despite these methods, feeding and medicating through a gastrostomy tube is the other option.
There is no preventive regimen for myasthenia gravis in dogs. Good home care requires administering medications exactly as prescribed and following any special feeding instructions. Since most dogs with this disorder die within 12 months as the result of aspiration pneumonia, the prognosis for recovery is guarded. However, from time to time, a dog with a mild case responds well to therapy and might experience a remission lasting for quite a few months.
Sources:
PetPlace.com site
Vetinto site
