When children with MCADD are sick, the illness can cause an acute crisis in which they need to visit the emergency room. They also need the appropriate care from doctors who understand how illness affects MCADD. Learn when your child should visit the emergency room if they are sick and how to tell the emergency doctors how to best treat your child.

What Is MCADD?

MCADD is a genetic condition in which your child’s body cannot break down fats properly for energy. MCADD stands for Medium Chain Acyl-CoA Dehydrogenase Deficiency.

How Does Illness Affect MCADD?

Children with MCADD need to eat regularly to stay healthy. It is not safe for children with MCADD to go for long periods of time without eating or drinking liquids with calories.

If your child is sick and eating or drinking less than usual, it can cause an acute crisis (a serious illness that needs emergency care). Without the appropriate emergency care, your child can get sicker. The acute crisis can also be life-threatening.

What Are the Signs of an Acute Crisis?

  • Lethargy (showing a serious lack of energy)
  • Vomiting or upset stomach
  • Will not or cannot eat
  • Seizures
  • Signs of low blood sugar, like shaking, sweating, feeling dizzy or feeling tired

What Should I Tell the Emergency Doctors?

Tell the ED doctor that your child has MCADD. Tell or show the ED doctor these directions.

  • STAT, check blood sugar (can be finger stick) and start oral glucose-containing solutions or IVF with dextrose. The IVF should never be less than 10% dextrose (with appropriate electrolytes).
  • Obtain the following electrolytes: VBG, LFTs, CPK and ammonia level. If your child has a fever, the ED doctor can also do a blood culture or other tests if they choose.
  • Follow the full Acute Illness Protocol (PDF) from the New England Consortium®.

What Should I Do if My Child Shows Signs of Acute Crisis?

For Mild Signs of Acute Crisis...

  1. Call your child’s pediatrician. The pediatrician might be able to check your child’s blood sugar, give advice and figure out if your child needs to go to the emergency room.
  2. Try to give your child juice or a sugary drink.

For Severe (Very Bad) Signs of an Acute Crisis...

  1. Go to the ED at Mass General for Children (MGfC). Before arriving at the emergency room, call MGfC at 617-726-2000 and ask the operator to page the genetics metabolism doctor on call. This will help the operator alert the doctors about your child’s condition.
  2. Bring these directions to the emergency room.


REv. 9/2017. This document is intended to provide health related information so that you may be better informed. It is not a substitute for a doctor's medical advice and should not be relied upon for treatment for specific medical conditions.