Glycogen storage disease Type VII, Phosphofructokinase Deficiency, PFK Deficiency

PFKM, Whippet and English Springer Spaniel Variant

Multisystem

This condition affects an enzyme needed for energy production in red blood cells and muscles. During intense activity or overheating, affected dogs may experience muscle injury and breakdown of red blood cells.

Signs and symptoms

Affected dogs can have pale gums, a high fever, jaundiced mucous membranes, and might produce brown-colored urine, the last two being due to high levels of bilirubin, a breakdown product of ruptured red blood cells (hemolysis) and skeletal muscle cells (rhabdomyolysis).

Signs often first appear at approximately 4-6 months of age.

Diagnosis

Treatment

Treatment for an acute episode often involves hospitalization with careful monitoring of laboratory values. Curing the disease requires a bone marrow transplant. Note that the clinical signs of PFK deficiency are very similar to those of other hemolytic diseases, including immune-mediated hemolytic anemia: If your dog is experiencing signs of hemolysis and anemia, testing your pup for the genetic mutations known to cause PFK deficiency helps you and your vet rule PFK deficiency in or out!

What to do if your dog is at risk

Talk to your vet about your dog’s PFK deficiency result so you can work together to plan ongoing care and monitoring.

Avoid strenuous exercise, overheating, or excessive excitement, as these can trigger red-blood-cell breakdown and anemia.

Keep your dog cool and calm, especially during warm weather or play, and provide access to fresh water and shaded areas.

Contact your vet if you notice signs such as weakness, fatigue, dark-colored urine, or rapid breathing.

Genetic information

This mutation was first described in the English Springer Spaniel and Whippet.

Penetrance: This mutation is inherited in an autosomal recessive manner; that is, a dog requires two copies of the mutation to show signs of the disease. Carriers have about one half normal enzyme activity in red blood cells and muscle tissue and are clinically normal.

Gene: PFKM (Exon 21)
Inheritance type: recessive
Clinical category: Multisystem