Common Types of Metabolic Disorders in Children
Here are a few major categories with examples:
1. Amino Acid Disorders
These affect how the body breaks down proteins.
- Phenylketonuria (PKU): Buildup of phenylalanine can cause brain damage if untreated.
- Maple Syrup Urine Disease (MSUD): Affects branched-chain amino acids, causes sweet-smelling urine and neurological damage.
- Homocystinuria: Leads to high levels of homocysteine, affecting the eyes, bones, and brain.
2. Carbohydrate Metabolism Disorders
- Galactosemia: Inability to process galactose (milk sugar); can cause liver damage, cataracts, and intellectual disability.
- Glycogen Storage Diseases (GSD): Trouble storing or releasing sugar; can cause low blood sugar, enlarged liver, and growth problems.
3. Fat Metabolism Disorders
- Medium-chain acyl-CoA dehydrogenase deficiency (MCADD): Trouble using stored fat for energy, especially during fasting.
- Carnitine deficiency: Affects energy production in muscles and heart.
4. Organic Acid Disorders
- Propionic acidemia, methylmalonicacidemia: Build-up of toxic organic acids; can cause vomiting, lethargy, seizures, and coma.
5. Mitochondrial Disorders
Affect the mitochondria, the energy-producing parts of the cell. Symptoms vary, including:
- Muscle weakness
- Developmental delays
- Seizures
- Hearing/vision loss
6. Peroxisomal Disorders
- Zellweger syndrome: Affects brain, liver, and kidneys; usually severe and diagnosed in infancy.
Common Signs & Symptoms
Symptoms depend on the type of disorder but may include:
- Poor feeding, vomiting
- Low blood sugar (hypoglycemia)
- Lethargy or excessive sleepiness
- Seizures
- Delayed growth or development
- Muscle weakness or floppy muscles
- Jaundice or liver enlargement
- Unusual urine or body odor