First some definitions so we can understand what we are talking about when we say PK Deficiency
First of all, the erythrocyte part of PK Deficiency is a red blood cell without a nucleus. Erythrocytes contain the pigment hemoglobin which gives blood its red color and its function is to give oxygen to tissues and in turn transport the carbon dioxide away from the tissue.
Pyruvate is an organic compound, a byproduct of Pyruvate Acid.
Pyruvate Acid helps to metabolize proteins and carbohydrates and release energy to the body.
Kinase is an enzyme. Kinases are a go-between that stabilize reactions of transfers from high energy to substrate molecules in the body.
Hemolytic means the rupture or destruction of red blood cells that cause anemia.
Erythrocyte Pyruvate Kinase Deficiency (PK Deficiency) is an inherited hemolytic anemia caused by insufficient activity of this regulatory enzyme which results in instability and loss of red blood cells. The anemia is intermittent, the age of onset is variable and clinical signs are also variable. This condition is inherited as a recessive gene in cats. A cat must carry two copies of the gene, meaning both parents are able to get sick from this disease or carry one copy and can pass it on.
Many cat breeds are affected by PK Deficiency: Abyssinian, Bengal, Egyptian Mau, La Perm, Maine Coon, Norwegian Forest Cat, Siberian, Singapura, Somali, regular non-specific breed house cats and the reason you are reading this on a Savannah cat website is because… yes, our dear Savannahs can be affected due to the fact that some of the same cats were bred in the Savannah lines.
It is not a pleasant experience for a cat nor its owner. Here are just some of the symptoms you might see in a cat who is positive for the disease:
- Mild to severe hemolytic anemia
- Hemochromatosis (too much iron in the body). The extra iron can build up in organs and cause damage.
- Enlarged Spleen
- Leg ulcers
- Shortness of breath
- Severe Lethargy
- Weight loss
- Abdominal enlargement
There is no cure for this disease. The only hope is for breeders to do a very easy test to make sure the cats they choose to breed do not carry for this disease. University of California, Davis offers a very reasonable test at their vgl lab https://www.vgl.ucdavis.edu/services/pkdeficiency.php for those breeders who would like to be sure their cats will not be passing on this tragic affliction. Responsible breeders, who want healthy cat and offspring will test every one of their cats and provide results to their buyers. Below is an explanation of the possible results and what they mean:
PK Deficiency Chart
Breeding Result Possibilities
N/N bred to N/N – No kittens will get the disease or pass it on.
N/N bred to N/K – Approximately ¾ of the kittens will not inherit PK Def. ¼ of the kittens will inherit and carry PK Def.
N/K bred to N/K – Approximately ½ of the kittens will inherit PK Def and many of the ½ will get the disease.
K/K bred to K/K – ALL kittens will inherit PK Def and WILL get the disease.