Sweet Pee

The truck slams into the wall over and over again, grasped firmly in the hyperactive hands of an overly energetic six year old boy. His declarations of a monster in the room have driven the putative occupants of the truck mad with fear, and his attempts to lead them into safety end only in repetitive disaster. His mother brought him in years ago, referred by a pediatrician after an offhanded comment. It's how most of them come to the genetics clinic, always for the subtle things. The major things get caught at birth, as they are usually sort of hard to miss.

She had remarked that her infant's urine smelled sweet. Smelled like maple syrup. Thats not normal, she probably asked, assuming, like most new mothers, that the Doctor would reassure her. But they didn't reassure her. They sent her here. Her son has Maple Syrup Urine Disease, the aptly named syndrome describing an enzymatic failure leading the urine to reek of a thousand McGriddles. Her child is missing a functional copy of the less fortuitously (but equally aptly) named branched chain alpha keto-acid dehydrogenase complex, the enzyme allowing us to break down the amino acids leucine, isoleucine, and valine. Her son can't clear these compounds (readily found in most protein) from his body, so they build up, increasing quantities generating neurotoxicity, neurotoxicity causing brain damage. Unmonitored, a healthy diet will leave her son mentally damaged, a slowly developing crescendo of diminished function.

It is one of the classic metabolic disorders, trailing only phenylketonuria in commonality. We don't know how it was missed in the neonatal screen, but its a great development that they caught it as soon as they did. Her son will be normal, so long as he watches his diet, staying away from milk, meat, and eggs. We have to test his blood frequently, monitoring the buildup of these normally crucial building blocks. Its a wonder, at age six, that he doesn't hate these visits more, the cruel men and women in the white coats, controlling his life and sticking him with needles. His mother, on the other hand, looks to us for quiet reassurance. She is doing her job well, we tell her. She is giving her son the chances he needs.

It most be odd, I think, to dread the smell of pancakes.