2025 – PAGE 351 – INBORN ERRORS OF METABOLISM & MISCELLANEOUS METABOLIC DISORDERS

ISOVALERIC ACIDEMIA

Isovaleric acidemia findings include an organic acidemia presentation with a history of a SWEATY FEET smell, poor feeding, and SEIZURE. Patients are especially prone to getting INFECTIONS, so look for a fever. Treatment should include PROTEIN RESTRICTION.

• PEARL: This one DOES NOT HAVE LACTIC ACIDOSIS! Isovaleric acid is not part of the ATP production pathway that produces lactate.
• MNEMONIC: It helps if you know someone named Eric for this one. Rename this as iso-WALL-ERIC in your mind. Imagine ERIC leaning on a WALL by himself at lunchtime. He’s DEPRESSED because he has SMELLY/SWEATY FEET. He likes a girl, but every time he gets near her, his SWEATY FEET make her have a SEIZURE. So he continues to stand there alone at lunchtime with NO APPETITE while everybody else eats STEAK for lunch and chats about all the fun they’re going to have at the CARNIVAL.
  • KEY: DEPRESSED = Lethargy. NO APPETITE = Poor feeding. STEAK = Protein. CARNIVAL = Carnitine.
• MNEMONIC: (IMAGE – Eric Cartman (from South Park) www.pbrlinks.com/ISOVALERIC1

GLUTARIC ACIDEMIA

Glutaric acidemia can also present with the smell of SWEATY FEET.

MNEMONIC: If you can connect ERIC with SMELLY FEET, you’re set: Glut-ERIC.

METHYLMALONIC ACIDEMIA & PROPIONIC ACIDEMIA

In methylmalonic acidemia and propionic acidemia, children present with poor feeding, vomiting, dehydration, lethargy, possibly hypotonia, and tachypnea. May look like pyloric stenosis or sepsis. Labs will show the elevated ammonia, acidosis, and elevated lactate. Diagnose with urine organic acids.

• MMA: Treat with B12!
  • MNEMONIC: Connect MMA with B12 by remembering that you obtain an MMA level to diagnose B12 deficiency!
• PROPIONIC ACIDEMIA: Treat with Biotin.