Do You Smell What I Smell?

This parody (written by Greg Crowther) is sung to the tune of "Do You Hear What I Hear?" (written by Noel Regney and Gloria Shayne Baker).

This Christmas song tells the story of a child who might grow up to be a great and powerful leader, but is currently just a baby who needs help. It was written for the 2017 holiday party of UW Nephrology, where my wife works. Thanks to Dr. Nisha Bansal for her help in creating it.

Said the mother to the resident,
"Do you hear what I hear
(Do you hear what I hear)
From my baby's crib, Resident?
Do you hear what I hear?
(Do you hear what I hear?)
My child, my child
Is crying through the night.
I can tell that something isn't right.
I can tell that something isn't right."

Said the resident to the junior fellow,
"Do you see what I see
(Do you see what I see)
In these lab results, my good fellow?
Do you see what I see?
(Do you see what I see?)
The child, the child,
Weakened with malaise,
Has elevated blood BCAAs!
He has elevated blood BCAAs!"

Said the fellow to the attending doc,
"Do you smell what I smell
(Do you smell what I smell)
In this diaper here, Attending Doc?
Do you smell what I smell?
(Do you smell what I smell?)
The scent, the scent
Of every little squirt
Of his urine smells like dessert!
Yes, his urine smells like dessert!"

Said the attending to the section chief,
"Do you know what I know
(Do you know what I know)
From these case reports, Section Chief?
Do you know what I know?
(Do you know what I know?)
The child, the child
Has got MSUD.
Let us bring him food that’s protein-free!
From this disease, we will set him free!"

(1) What does MSUD stand for? Is this condition inherited or acquired?

(2) What does BCAA stand for?

(3) Why will a person suffering from MSUD be helped, acutely, by a switch to a low-protein or protein-free diet?

(Answers may be found on the answers page.)