MCAD deficiency is a genetically inherited disorder. MCAD stands for medium-chain acyl-CoA dehydrogenase. It is an autosomal recessive disorder. It is a disorder related to fatty acids oxidation, especially the medium chain fatty acids. The characteristic sign of MCAD deficiency is a very serious hypoglycemia and sudden death.
How Is MCAD Deficiency Diagnosed?
- MCAD deficiency and many other disorders related to fatty acid oxidation are doubted in the persons who suffer from hypoketotic hypoglycemia, seizures, coma and lethargy, more so if any of these is caused because of an illness.
- A person suffering from hepatomegaly and acute liver disease is also checked for MCAD deficiency.
- MCAD is often misdiagnosed with Reye syndrome.
- In some cases, a sudden death after a minor illness can raise a suspicion of MCAD deficiency and is found in most such cases.
- When new-born screening is done using tandem mass spectrometry, MCAD deficiency is found within a short duration of birth. This is checked by collecting blood spots on filter paper.
- Elevated carnitine levels might be suggestive of MCAD deficiency disorder in infants and mothers are suspected and checked for the same, where they are found to be positive for the test.
Urine tests are done which consist of organic acid analysis, which is done by using gas chromatography- mass spectrometry (GC-MS). This test will reveal dicarboxylic aciduria with reduced levels of ketones.
- Acylglycine traces may be seen in the urine
- Many asymptomatic persons may be having very normal lab findings. Detecting MCAD deficiency in such cases can be difficult. However, GC-MS can give diagnostic results in such cases
- After this initial suspicion and techniques for diagnosing MCAD deficiency are carried out, a genetic analysis of ACADM is then done to further confirm the diagnosis
- If a person dies a sudden death and there is a history of an illness which should not be fatal otherwise, the probability of MCAD deficiency is usually suspected
- The autopsy may reveal fatty deposits in liver
- Postmortem analysis of bile and blood for acylcarnitine can be done to confirm the diagnosis
- If parents and siblings are asymptomatic, their biochemical lab analysis can also be helpful in diagnosing the condition
- MCAD deficiency and many other fatty acid oxidation disorders are considered to be one of the causes of SIDS, that is sudden infant death syndrome
Treatment Of MCAD Deficiency
- Keeping away from long, extended periods of fasting is of utmost importance in MCAD deficiency
- People affected by any fatty acid oxidation disorders need to be very vigilant about this factor
- If you are suffering from an illness, any type of metabolic distress should be avoided at all costs
- To achieve this, it is advisable to take a simple carbs or glucose supplement so that catabolism can be prevented
- The duration of fasting differs from a person to person. Long fasting periods are to be avoided no doubt, but the age factor is to be considered
- Usually what a person can tolerate as a fasting period can be significantly changed for a person affected with MCAD during or due to an illness. This should be kept in mind at all times
The most important precautionary measure that has to be considered is that if you suffer from MCAD you must carry an emergency note or letter. In your pocket at all times. The letter should clearly indicate what disorder you are suffering from along with basic treatment guidelines if any. This is particularly helpful if you are traveling or have chances of landing in an unknown place with unknown doctors and nurses. In any case, it is in your best interest to carry a note about the disorder that you are suffering from, so that there is no more delay in starting the needed treatment immediately.
MCAD deficiency is a genetically inherited autosomal recessive disorder. It is characterized by severe and a dangerous hypoglycemia and can result in sudden death if the treatment is delayed.