L-Carnitine Deficiency in Cats

L-Carnitine is a water soluble molecule found within the cells of the body and concentrated in skeletal and cardiac muscles. This vitamin-like molecule’s primary function to the feline is to facilitate long chain, amino fatty acid transportation across the mitochondria. The mitochondria houses the production of energy, which L-Carnitine aids in oxidizing, therefore, providing energy to the body and playing a role in the oxidation of fat. An L-Carnitine deficiency means that the body has an inadequate quantity of the molecule, delaying L-Carnitine synthesis and leading to heart and skeletal muscle health problems. 

L-Carnitine is an essential vitamin-like molecule that your cat needs to regulate the heart and skeletal muscles, as well as release energy and break down fats in the body. L-Carnitine is housed within the cells of the heart and skeletal muscle and carried throughout the blood. These muscle structures cannot make energy or breakdown fats without L-Carnitine, so when the body lacks this specialized molecule, cellular energy is lost and heart disease is soon to follow. 

Symptoms of an L-Carnitine deficiency in cats can be difficult to detect, but most pet owners will identify muscle pain by simply picking up the feline. Without L-Carnitine, the cells cannot utilize the body’s fat storage used for energy production, which is required for muscle, heart and brain function. Therefore, an L-Carnitine deficiency in cats will have a negative impact the entire body causing symptoms and conditions such as:

• Heart disease
• Heart failure
• Heart enlargement or dilated cardiomyopathy 
• Intolerance to exercise
• Pain in the skeletal muscles
• Lethargy

The exact cause of L-Carnitine Deficiency is still to be determined, however, research has found that when a supply of L-Carnitine is no longer consumed by the cat, a deficiency can develop. L-Carnitine is found in meat and dairy products, which are readily consumed by the feline, spreading throughout the body. Obese cats that are placed on crash diets and stray cats are more prone to developing an L-Carnitine deficiency due to the sudden decrease in L-Carnitine consumption level. Other cases of L-Carnitine deficiency have been found in cats with idiopathic hepatic lipidosis, commonly known as fatty liver disease.

Diagnosis of L-Carnitine deficiency in cats will begin with a physical examination and review of the patient’s medical history. Important information you can provide the veterinarian to aid in his/her deduction includes: 

• When you first noticed the signs or symptoms.
• What type of symptoms have you noted at home? 
• How long has your cat been displaying these symptoms? 
• Have you made any recent changes to your cat’s diet? 

Having the answers to these questions will clue your veterinarian in as to what the possible underlying condition may be and which diagnostic exam to perform next. 

Next, your veterinarian may perform a blood plasma test to determine the level of L-Carnitine molecules streaming through the blood. A plasma test will be helpful, but it may not be enough to make a direct connection to an L-Carnitine deficiency. Therefore, a biopsy of the heart muscles, called an endomyocardial biopsy, may be performed to test the levels right from the source. X-rays and an ultrasound might also follow in diagnostic procedures to note evidence of dilated cardiomyopathy. 

The main objective of treatment of an L-Carnitine deficiency in cats is to replenish the body’s supply. L-Carnitine supplements are the most common treatment option for cats with this type of deficiency, but it is not the best treatment option for all cats, as each body reacts differently to the drug. Ask your veterinarian about the best treatment option for your cat with L-Carnitine deficiency. 

If you have recently placed your cat on a diet, the vet may ask you to discontinue the diet until the feline’s health improves. A diet change is not uncommon in cats with L-Carnitine deficiency. Cat food specially formulated to aid the body in L-Carnitine production is available at your local veterinary clinic, but should only be used under veterinary consultation. 

There is no cure for L-Carnitine deficiency in cats and many cats do not completely recuperate, even after treatment is administered. However, you can improve your cat’s quality of life by following up with the veterinarian as directed and following the doctor’s recommendations at home. Due to the effects L-Carnitine deficiency has on the heart, your veterinarian may examine the muscle regularly though an echocardiogram. An echocardiogram will allow the veterinarian to test the heart’s function and reevaluate the current treatment if necessary.