Panel members: Richard Allen, M.D., Anna Marie Schaefer, R.D., MPH., Dean Danner, PhD.
The issue of classifications was discussed at length. The original classifications included classic, intermediate, intermittent, and thiamine responsive. These descriptions are based on the clinical differences, leucine tolerance and response to thiamine. They do not necessarily correlate with the enzyme assays. The consensus seems to be that with so many unknowns and variations metabolic classifications are inadequate. Determining the mutation may be a better way to indicate type of MSUD. Hopefully a mouse model will help in determining differences.
One mother asked about how to increase the calories in the diet of her 14 year old boy who is small and thin for his age. If they add high calorie supplements, his appetite is affected and he won't eat. Children with MSUD vary in size and weight and it is hard to know what is genetic and what may be the effects of nutrition.
A mother said her daughter was turned down when she wanted to give blood. Both Dr. Allen and Dr. Danner said there was no biological reason a person with MSUD can not be a blood donor. However, a knowledgeable person needs to be contacted and not just the person drawing the blood.
Doctors in Australia told a mother TPN is too expensive and lipids do the same thing. Dr. Allen explained that TPN has been used all over the world for many years, but TPN for MSUD is revised with the branched-chain amino acids removed. Massive doses of lipids can cause other metabolic problems. Individuals with MSUD need the protein in the TPN.
The best levels to maintain in a child with MSUD depends on whether you are trying to attain a preconceived number or are based on how the child reacts. Would the child grow better with a little higher level? The labels are wrong. Whether the child is classic, mild or intermittent is not important and can lead to confusion. A child that is not gaining weight or losing weigh is catabolic regardless of how "good" the blood level is. Ultimately the child needs to be kept at the level that will keep that child healthy and growing.
There are various effective treatments which vary with the individuals and different clinics. But when a child starts showing neurological (brain stem) involvement - not cerebral edema - Dr. Allen gives that child TPN. This usually results in a rapid and full recovery without any other treatment.
A mother stated there was no doctor or center involved in treating MSUD near them. Dr. Allen says we need to find a way to help physicians and pediatricians understand that MSUD is a real disorder, and there are newer and different ways to treat these children. However, it is still remarkably better than it was 10 years ago.