Metabolic Disease

Question 1

Ferric Chloride Test

Answer 1

• Alkaptonuria (Homogentesic Acid)
• MSUD
• Melanoma (Melanin)
• PKU

Question 2

Ammoniacal Silver Nitrite

Answer 2

Alkaptonuria (Homogentesic Acid)

Question 3

Benedict’s Test

Answer 3

Alkaptonuria (Homogentesic Acid)

Question 4

Nitrosonaphthol Test

Answer 4

Tyrosinuria

Question 5

Hoesch Test and Watson-Schartz Test

Answer 5

Porphyria (Porphobilinogen)

Question 6

Organs actively involved in the metabolism of Amino Acids

Answer 6

Liver and Kidney

Question 7

Interconversion of Amino Acid

Answer 7

Transamination

Question 8

Degradation of Amino Acid

Answer 8

Deamination

Question 9

INCREASE in the plasma levels of AA

Answer 9

Overflow Aminoaciduria

Question 10

What will happen to the renal threshold of amino acid in overflow aminoaciduria?

Answer 10

Exceed –> additional AA are excreted in urine

Question 11

Amino acids are not reabsorbed by the tubules
INCREASE in blood = INCREASE in urine

Answer 11

No-Threshold Aminoaciduria

Question 12

Aminoaciduria caused by Defect in tubules (congenital/acquired) –> AA not reabsorbed by the tubules

Answer 12

Renal Aminoaciduria

Question 13

What is the plasma level in renal aminoaciduria?

Answer 13

Normal

Question 14

A.k.a. “inborn errors of metabolism”
Result from: INHERITED DEFECT

Answer 14

Primary Aminoaciduria

Question 15

2 types of defect in primary aminoaciduria

Answer 15

1. Enzyme is defective (deficient) in the SPECIFIC AA metabolic pathway
2. Tubular Reabsorptive Dysfunction

Question 16

Induced by: SEVERE LIVER DISEASE or GENERALIZED TUBULAR DYSFUNCTION (e.g. Fanconi Syndrome)

Answer 16

Secondary Aminoaciduria

Question 17

Lysosomal storage disease that results in deposition of cystine in the lysosomes of cells throughout the body (kidneys, bone marrow, spleen)

Answer 17

Cystinosis

Question 18

Give the Mode of Inheritance for Cystinosis

Answer 18

Autosomal recessive

Question 19

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

Answer 19

Nephropathic Cystinosis

Question 20

When is Nephropathic Cystinosis evident?

Answer 20

First year of life

Question 21

RARE FORM
Clinical Features: SAME with Nephropathic Cystinosis

Answer 21

Intermediate Cystinosis

Question 22

When is intermediate cystinosis evident?

Answer 22

Adolescence

Question 23

RARE FORM
CYSTINE DEPOSITION in the CORNEA → Ocular Impairment

Answer 23

Ocular Cystinosis

Question 24

This is due to NEPHRONES (PTC) = UNABLE to REABSORBED AA (cysteine, dibasic AA e.g. arginine, lysine, ornithine)

Answer 24

Cystinuria

Question 25

What is the Mode of Inheritance for Cystinuria

Answer 25

Autosomal recessive

Question 26

Accumulation of branched-chain AA (leucine, isoleucine, valine) and their corresponding α-keto acids in BLOOD, URINE & CSF *give the MOI

Answer 26

Maple Syrup Urine Disease (*Autosomal Recessive)

Question 27

Deficient Enzyme in MSUD

Answer 27

Branched-Chain α-Keto Acid Dehydrogenase (BCKD)

Question 28

INCREASED urinary excretion of PHENYLPYRUVIC ACID (a ketone) and its metabolites *give the MOI

Answer 28

Phenylketonuria (*Autosomal recessive)

Question 29

Deficient Enzyme in PKU

Answer 29

PHENYLALANINE HYDROXYLASE

Question 30

Give the characteristic of urine, sweat and breath in PKU (and its cause)

Answer 30

Mousy/Musty odor (caused by Phenylacetic acid)

Question 31

Excretion of large amount of HOMOGENTISIC ACID (HGA) in the urine *give the MOI

Answer 31

Alkaptonuria (*Autosomal recessive)

Question 32

Deficient enzyme in Alkaptonuria

Answer 32

HOMOGENTISIC ACID OXIDASE

Question 33

Increased amount of TYROSINE in the urine → occurs when → tyrosine levels in PLASMA is abnormally high

Answer 33

Tyrosinuria

Question 34

Defective melanin production will result to

Answer 34

Hypomelanosis/Albinism

Question 35

Increased excretion of urinary melanin = INCREASED production of MELANIN & its colorless precursors (e.g. 5,6- dihydroxyindole)

Answer 35

Melanuria

Question 36

Polyuria with presence of glucose in the urine HIGH:SG

Answer 36

Diabetes Mellitus

Question 37

Diabetes means

Answer 37

copious amount of urine (POLYURIA) that this disorder produces

Question 38

Mellitus means

Answer 38

Sweet

Question 39

Refers to bland taste of urine produced Low: SG

Answer 39

Diabetes Insipidus

Question 40

Inability to properly metabolize galactose to glucose

Answer 40

Galactosemia

Question 41

Give the 3 enzymes responsible for Galactosemia

Answer 41

1. Galactose 1-phosphate uridylyltransferase (GALT) 2. Galactokinase (GALK) 3. Uridine diphosphate galactose-4-epimerase (GALE)