3yr old sweat smells like maple syrup

[Antlss]

Our grandson has always smelled like maple syrup since birth, not his urine - I believe it's his sweat. I, of course, thinks he's sweet....but am concerned. He had a sleepover this weekend and even his sheets smelled like syrup when I went to wash them. Should I be concerned? And if so, what of?

[John Kenyon, CNA]

Hello -

There is a specific metabolic disorder which can cause this odd symtom, and it's known as Maple Syrup Urine Disease (MSUD). It's caused by the body's inability to break down certain amino acids, and it can be realtively mild and cause little to no problem, or it can, in some cases, cause some nutrition-related problems that require medical treatment. It would probably be useful to have the child checked for this specific missing enzyme, but it sounds as though he is relatively healthy, so he may only have a very mild form (or he may not have this at all). I don't know what the treatment is for this, but I've never encountered any great deal of concern about it among doctors, either, so while it does need ruling in/out, I believe it is a manageable problem, if, indeed, it's even present.

I hope this answers your question. Best of luck to you.

[Dr. Chan Lowe]

Hi Antiss,

For some reason, some children will periodically have a maple syrup smell in their sweat. The etiology of this is not known and it appears that in most cases it goes away on its own.

The most common form of maple syrup urine disease (MSUD) presents rapidly after birth and can be fatal if not treated. It would be nearly impossible for this to be the case if your son is 3 years old and has not been being treated.

There is an intermediate form of the disease that can present at an older age; however, this is quite rare and I believe there are only 20-30 cases known world wide. Also, there are some intermittent forms that present with symptoms when the body is stressed (such as during illness). The common symptoms of MSUD include neurological manifestations including coordination problems, seizures, etc.

If this problem does not resolve I would recommend you have your son see his doctor for further evaluation. If there is concern, a metabolic geneticist would be the specialist to consult.

Best wishes.