Inborn Errors of Metabolism Flashcards
Examples of inborn errors of metabolism with metabolic acidosis and elevated ammonia
Proprionic acidemia
Methylmalonic acidemia
Fatty acid oxidation
Examples of inborn errors of metabolism with metabolic acidosis and normal ammonia
MSUD
Some organic acidemias
Examples of inborn errors of metabolism with normal pH and elevated ammonia
Urea cycle defect
Transient hyperammonemia
Examples of inborn errors of metabolism with normal pH and normal ammonia
Aminoacidopathy
Galactosemia
Non-ketotic hyperglycemia
Typically present in first 2 days of life
Following intro of protein
“Drunk-like”
Elevated ammonia
HAGMA
Ketonuria
Organic acidemias
-Methylmalonic
-Proprionic
-Isovaleric
Management of organic acidemias
Hydration
Appropriate diet
First 2 years of life
Hypoglycemia (hypoketotic)
Hepatomegaly (elevated LFTs)
Seizure
Poor PO
Elevated ammonia
Treatment
Fatty acid oxidation defects
(Autosomal recessive)
-MCAD, LCAD, VLCAD
-Glutaric aciduria
Tx: Carnitine
Definitive diagnosis for fatty acid oxidation defect and management
Plasma acylcarnitine profile
Emergent IV 10% glucose and oral L-carnitine
Normal at birth
Poor feeding and FTT after intro to lactose
Hepatomegaly
Hypoglycemia
Lethargy/hypotonia
Positive reducing substances in urine
E. coli sepsis
Galactosemia
Definitive diagnosis of galactosemia and management
GALT in RBC
(Deficiency in galactose-1-phosphate uridyltransferase)
Galactose-free diet (soy formula)
Complications of galactosemia
Cataracts
Reversible with diet change
Afebrile
Seizures
Persistent hypoglycemia
Low BHB
Low free fatty acids
Large head and body
Hyperinsulinism
Hypoglycemia
Hepatomegaly
Doll-like or cherubic face
FTT
Lactic acidosis
Glycogen storage disease type 1
(Von Gierke Disease)
Deficiency of hepatic glucose-6-phosphatase
Floppy
FTT
Cardiomegaly
Hepatomegaly
Macroglossia
Respiratory failure
Glycogen storage disease type II
(Pompe disease)
Deficiency in lysosomal breakdown of glucose
Hyperammonemia
Acidosis
Ketosis
Organic aciduria
Hyperammonemia
No acidosis
No ketosis
Urea cycle defect
Maple syrup urine disease is caused by the inability to break down these amino acids
Dietary treatment
Valine
Isoleucine
Alloisoleucine
Leucine
Branched amino acid restriction
Motor dysfunction
Behaviors disturbances
Self-inflicted injuries
Urate:Cr ratio > 2 (diagnostic)
Elevated serum uric acid level
Lesch-Nyhan syndrome
Deficiency of the HGPTY enzyme
Error in methionine metabolism
Posterior lens displacement
Possible cognitive deficits
Light skin, hair, eyes
Thromboembolic events
Homocystinuria
Newborn after intro to protein formula
Lethargy
Coma
Spastic CP
Nonketotic hyperglycinemia
Blond hair. Blue eyes
Musty or mousy urine odor
Phenylketonuria (PKU)
Plasma amino acid
Presents before age 2
Facial coarsening
Hirsutism
HSM
Corneal clouding
Reduced alpha-L-iduronidase
Dystopia multiplex
Hurler Syndrome
(Mucopolysaccharide type 1)
Coarse facial features
Organomegaly
NO corneal clouding
Join contractures
Pebbly skin
Deafness
Reduced iduronate sulfatase enzyme
Hunter syndrome
(Mucopolysaccharide type II)
X-linked recessive
HSM
Bone pain (osteosclerosis, lytic lesions)
Easy bruisability (thrombocytopenia)
Short stature
Erlenmeyer flask deformity
Gaucher disease
Exaggerate startle reflex
Cherry red spot on retina
Macrocephaly
Blindness. Seizures.
Hexosaminidase A enzyme deficiency
Tay Sachs disease
Autosomal recessive
Cherry red spot on retina
CNS deterioration
HSM
Niemann-Pick disease
Encephalopathy
Lactic acidosis
Stroke
Mitochondrial disorder
(MELAS)
Complication of Hunter syndrome
Cardiac valvular leaflet dysfunction
Death
Hepatic/renal dysfunction
FTT
RTA/Fanconi syndrome
Rickets
Hepatorenal tyrosinemia (Type1)
