Non-inflammatory Metabolic Myopathy in Cats

 

Non-inflammatory metabolic myopathy is a rare muscle disease associated with metabolic disorders like various enzyme defects or storage of abnormal metabolic byproducts and others. Unfortunately, little is known about how the disorder affects cats exactly.

 

Symptoms and Types

 

• Muscular weakness
• Cramps
• Exercise intolerance
• Regurgitation and/or difficulty swallowing (dysphagia)
• Collapse
• Dark urine
• Vomiting
• Abdominal distention

 

Causes

 

• Congenital (born with this problem) error in metabolism
• Acquired (later in life) problems in metabolism
• Viral infections
• Drug exposure
• Environmental factors

 

Diagnosis

 

You will need to give a thorough history of your cat’s health, the onset and nature of the symptoms, to your veterinarian. He or she will then conduct a complete physical examination as well as a biochemistry profile, urinalysis, and complete blood count -- the results of which may show abnormalities related to metabolic problems involved. For example, the biochemistry profile may show abnormal levels of serum creatine (enzyme found in muscle, brain, and other tissues) and abnormally low levels of glucose (hypoglycemia).

 

Your veterinarian may also choose more enzyme assays and other specific testing to determine the cat's levels of amino acids, organic acids, and creatine. DNA-based tests, meanwhile, are used to identify specific carriers.

 

Often, a muscle tissue sample will be sent to a veterinary pathologist for further evaluation. This may reveal abnormal accumulation of fats or glycogen within muscle cells.

 

 

Treatment

 

Treatment varies with the type of metabolic defect and extent of your cat's symptoms. In most cases, there is little to be done for those suffering from metabolic defects.  If the cat suffers from seizures, decreased body glucose, or brain issues, it will need to be hospitalized and placed in intensive care.

 

Living and Management

 

Depending on the type of metabolic defect, diet restrictions may be put in place, especially if the defect has led to hypoglycemia. Discuss with your veterinarian about a feeding plan and do not allow the cat to exercise strenuously.

 

Overall prognosis depends on the type and extent of the metabolic defect, but a veterinarian will always advise against breeding the cat due to high probability of passing along the defect.