Metabolic Disease Flashcards
Ferric Chloride Test
- Alkaptonuria (Homogentesic Acid)
- MSUD
- Melanoma (Melanin)
- PKU
Ammoniacal Silver Nitrite
Alkaptonuria (Homogentesic Acid)
Benedict’s Test
Alkaptonuria (Homogentesic Acid)
Nitrosonaphthol Test
Tyrosinuria
Hoesch Test and Watson-Schartz Test
Porphyria (Porphobilinogen)
Organs actively involved in the metabolism of Amino Acids
Liver and Kidney
Interconversion of Amino Acid
Transamination
Degradation of Amino Acid
Deamination
INCREASE in the plasma levels of AA
Overflow Aminoaciduria
What will happen to the renal threshold of amino acid in overflow aminoaciduria?
Exceed –> additional AA are excreted in urine
Amino acids are not reabsorbed by the tubules
INCREASE in blood = INCREASE in urine
No-Threshold Aminoaciduria
Aminoaciduria caused by Defect in tubules (congenital/acquired) –> AA not reabsorbed by the tubules
Renal Aminoaciduria
What is the plasma level in renal aminoaciduria?
Normal
A.k.a. “inborn errors of metabolism”
Result from: INHERITED DEFECT
Primary Aminoaciduria
2 types of defect in primary aminoaciduria
- Enzyme is defective (deficient) in the SPECIFIC AA metabolic pathway
- Tubular Reabsorptive Dysfunction
Induced by: SEVERE LIVER DISEASE or GENERALIZED TUBULAR DYSFUNCTION (e.g. Fanconi Syndrome)
Secondary Aminoaciduria
Lysosomal storage disease that results in deposition of cystine in the lysosomes of cells throughout the body (kidneys, bone marrow, spleen)
Cystinosis
Give the Mode of Inheritance for Cystinosis
Autosomal recessive
Type of cystinosis that is the most common and severe form. Caused by the accumulation of cystine crystals in the proximal tubular cells of the nephrons causing generalized dysfunction –> fanconi syndrome
Nephropathic Cystinosis
When is Nephropathic Cystinosis evident?
First year of life
RARE FORM
Clinical Features: SAME with Nephropathic Cystinosis
Intermediate Cystinosis
When is intermediate cystinosis evident?
Adolescence
RARE FORM
CYSTINE DEPOSITION in the CORNEA → Ocular Impairment
Ocular Cystinosis
This is due to NEPHRONES (PTC) = UNABLE to REABSORBED AA (cysteine, dibasic AA e.g. arginine, lysine, ornithine)
Cystinuria
What is the Mode of Inheritance for Cystinuria
Autosomal recessive
Accumulation of branched-chain AA (leucine, isoleucine, valine) and their corresponding α-keto acids in BLOOD, URINE & CSF *give the MOI
Maple Syrup Urine Disease (*Autosomal Recessive)
Deficient Enzyme in MSUD
Branched-Chain α-Keto Acid Dehydrogenase (BCKD)
INCREASED urinary excretion of PHENYLPYRUVIC ACID (a ketone) and its metabolites *give the MOI
Phenylketonuria (*Autosomal recessive)
Deficient Enzyme in PKU
PHENYLALANINE HYDROXYLASE
Give the characteristic of urine, sweat and breath in PKU (and its cause)
Mousy/Musty odor (caused by Phenylacetic acid)
Excretion of large amount of HOMOGENTISIC ACID (HGA) in the urine *give the MOI
Alkaptonuria (*Autosomal recessive)
Deficient enzyme in Alkaptonuria
HOMOGENTISIC ACID OXIDASE
Increased amount of TYROSINE in the urine → occurs when → tyrosine levels in PLASMA is abnormally high
Tyrosinuria
Defective melanin production will result to
Hypomelanosis/Albinism
Increased excretion of urinary melanin = INCREASED production of MELANIN & its colorless precursors (e.g. 5,6- dihydroxyindole)
Melanuria
Polyuria with presence of glucose in the urine
HIGH:SG
Diabetes Mellitus
Diabetes means
copious amount of urine (POLYURIA) that this disorder produces
Mellitus means
Sweet
Refers to bland taste of urine produced
Low: SG
Diabetes Insipidus
Inability to properly metabolize galactose to glucose
Galactosemia
Give the 3 enzymes responsible for Galactosemia
- Galactose 1-phosphate uridylyltransferase (GALT)
- Galactokinase (GALK)
- Uridine diphosphate galactose-4-epimerase (GALE)
