MCKAT: Medium-Chain 3-Ketoacyl-CoA Thiolase Deficiency

Medium chain 3-ketoacyl-CoA thiolase deficiency is a type of genetic condition where a person cannot properly break down certain types of fats. This prevents the body from creating needed energy during times of stress, illness, fasting, and exercise, which can lead to medical symptoms. The body usually gets its energy by breaking down, or burning, fats and sugars.

MCKAT Deficiency

Unknown

The gene that causes MCKAT deficiency and the way it is inherited is not currently known.

MCKAT deficiency is very rare, and the exact frequency is unknown. MCKAT deficiency is the rarest FAOD.

Male

There is limited information about the signs and symptoms of MCKAT deficiency since so few cases have been reported.

In the first reported case, a 2-day-old baby showed signs of:

• Vomiting
• Dehydration
• Acidic blood (metabolic acidosis)
• Liver disease
• Severe muscle breakdown (rhabdomyolysis)
• Reddish-brown urine (myoglobinuria)

Older patients have shown other signs and symptoms, including:

• Low blood sugar (hypoglycemia)
• Vomiting
• Floppiness/poor muscle tone (hypotonia)
• Coma if the time between feedings is too long (fasting intolerance)
• Enlarged heart (cardiomyopathy)

In one case, the first sign of MCKAT deficiency was sudden death.

There is very limited information on how babies with MCKAT were diagnosed. The only extensive reports were taken from the first case of MCKAT which occurred in a 2-day old baby. Testing showed high levels of lactic acids, ketones, and dicarboxylic acids. Testing on skin cells showed that certain fats made little energy. Testing also showed low MCKAT activity levels and reduced MCKAT protein.

No

Before beginning any treatment or therapy, please consult with your physician. There are no established treatments for MCKAT deficiency. Individuals with symptoms like dehydration, low blood sugar, and heart malfunctions should be treated immediately as they could have one of the many other fatty oxidation disorders. It is important to stay in close contact with your child’s doctor as new treatments may develop over time.

• MCKAT Deficiency | Fatty Acid Oxidation Disorders Diagnosis – The INFORM Network
• Newborn screening information for medium-chain ketoacyl-CoA thiolase deficiency | Baby’s First Test

Connecting with others impacted by a rare disease allows for vital information to be shared about day-to-day life, prevents isolation, and gives hope. Please contact MitoAction for peer support opportunities at 888-MITO-411 or email mito411@mitoaction.org.

Other resources we recommend are:

• New Patient Kit for Mitochondrial Conditions
• Planning and Preparation
• Monthly Expert Series
• Energy in Action Podcast