[AUBF] Chapter 7 - Urine Screening For Metabolic DSD

2 CATEGORIES OF AMINOACIDURIA:
increase of Amino acid in BLOOD
increase of Amino acid in URINE
PKU, MSUD, CYTINOSIS

2 CATEGORIES OF AMINOACIDURIA:
N - Amino acid in BLOOD
Increase of Amino acid in URINE
Cystinuria, Fanconi’s Syndrome

Failure to inherit a gene that codes for a particular enzyme

NO enzyme

The most well-known of the aminoacidurias

NO PHENYLALANINE HYDROLASE

Other forms are due to lack of tetrahydrobiopterin

“MOUSY” urine, sweat, and breath odor

due to Phenylacetic acid

May lead to severe mental retardation

[ SCREENING TEST ] FOR PHENYLKETONURIA
FeCl3 TUBE TEST

[ SCREENING TEST ] FOR PHENYLKETONURIA

PHENISTIX STRIP

[ SCREENING TEST ] #3 FOR PHENYLKETONURIA

[ CONFIRMATORY TEST ] FOR PHENYLKETONURIA

inhibits the growth of B. subtilis

(+) PHENYLALANINE counteracts the action of

B2-TE (bacterial inhibitor) = ?

ZONE OF INHIBITION
(+) Growth = ?

ZONE OF INHIBITION
(-) Growth = ?

May also be seen in severe liver dsx

“RANCID BUTTER” urine odor

No Gene that codes for:

TYPE 1: Fumarylacetoacetate hydrolase (FAH)

TYPE 2: Tyrosine aminotransferase (TAT)

TYPE 3: p-hydroxyphenyl pyruvic acid dioxygenase

[ SCREENING TEST ] FOR TYROSYLURIA/TYROSINEMIA

FeCl3 TUBE TEST = ?

[ SCREENING TEST ] FOR TYROSYLURIA/TYROSINEMIA

NITROSO-NAPHTHOL = ?

[ CONFIRMATORY TEST ] #1 FOR TYROSYLURIA/TYROSINEMIA

[ CONFIRMATORY TEST ] #2 FOR TYROSYLURIA/TYROSINEMIA

NO HOMOGENTISIC ACID OXIDASE

Urine darkens after becoming ALKALINE from standing @RT

BROWN- or BLACK-stained cloth diapers

Reddish-stained disposable (plastic) diapers

Homogentisic acid causes black pigmentation in the connective tissues and ears (Ochronosis)

[ SCREENING TEST ] FOR ALKAPTONURIA

FeCl3 TUBE TEST = ?

[ SCREENING TEST ] FOR ALKAPTONURIA

CLINITEST = ?

[ CONFIRMATORY TEST ] #1 FOR ALKAPTONURIA

[ CONFIRMATORY TEST ] #2 FOR ALKAPTONURIA

Caused by MELANOMA (tumor involving melanocytes)

Tumor secretes 5,6-dihydroxyindole, which oxidizes to melanogen then to melanin

Urine darkens upon AIR EXPOSURE

Deficient production of melanin = ALBINISM

[ SCREENING TEST ] FOR MELANURIA

FeCl3 TUBE TEST = ?

[ SCREENING TEST ] FOR MELANURIA

SODIUM NITROPRUSSIDE TEST = ?

[ SCREENING TEST ] FOR MELANURIA

EHRLICH TEST = ?

Most common IEM in the PHILIPPINES

NO Branched-chain alpha-keto acid dehydrogenase

INCREASE OF Ketoacids of Leucine, Isoleucine, & Valine

“Caramelized sugar/Maple syrup/Curry” urine odor

Presence of Ketonuria in a newborn is significant

[ SCREENING TEST ] FOR MAPLESYRUP URINE

2,4-DINITROPHENYLHYDRAZINE (DNPH) = ?

[ CONFIRMATORY TEST ] FOR MAPLE SYRUP URINE

“Sweaty feet” urine odor due to isovalerylglycine

ORGANIC ACIDEMIAS #2

Detected using P-NITROANILINE TEST = (+) EMERALD GREEN COLOR

Indigo blue urine color (upon air exposure)

seen in:

HARTNUP DSX = BLUE DIAPER SYNDROME

intestinal dsds

[ SCREENING TEST ] FOR INDICANURIA

Tumor of Argentaffin/Enterochromaffin cells >>>

produce Serotonin = metabolized into 5-HIAA

px must NOT EAT bananas, pineapples, tomatoes,

chocolates, walnuts plums, and avocado

[ SCREENING TEST ] FOR ARGENTAFFINOMA
FeCl3 TUBE TEST = ?

[ SCREENING TEST ] FOR ARGENTAFFINOMA

NITROSONAPHTHOL W/ NITROUS ACID TEST = ?

URINE ODOR = “SULFUR”

TREATMENT = D-PENICILLAMINE

[ TESTS ] FOR CYSTINE DSDs

Brand’s modification of Legal’s niitroprusside

REAGENT = ?

[ TESTS ] FOR CYSTINE DSDs #2

Renal type of aminoaciduria

defective tubular reabsorption of:

d. Arginine

a. Cystine (less soluble) = Crystal formation

b. Ornithine

c. Lysine

Overflow type of aminoaciduria

(-) gene that codes for an enzyme responsible for cystine metabolism

TYPES = Nephropathis cystinosis, intermediate cystinosis, and ocular cystinosis

Cystine deposits in many areas of the body (BM, cornea, lumph nodes, and internal organs)

Defects in the metabolism of Methionine = increase of Homocyctine

NO Cystathione beta-synthase

[ SCREENING TEST ] FOR HOMOCYSTINURIA

SILVER-NITROPRUSSIDE TEST = ?

Dsds of Porphyrin metabolism

Urine color = Red/purple/burgundy-red/purplish

red/portwine

Colorless in LEAD POISONING

[ SCREENING TEST ] FOR PORPHRYIN DSDs

detects D-ALA, Porphobilinogen

[ SCREENING TEST ] FOR PORPHRYIN DSDs

Tests for Uroporphyrin, coproporphyrin, & protoporphyrin

[ SCREENING TEST ] FOR PORPHRYIN DSDs

CDC-recommended test for LEAD POISONING

Impaired metabolism of mucopolysaccharides/glycosaminoglycans

Frequently found in urine are DERMATAN SULFATE, KERATIN SULFATE, & HEPARIN SULFATE

[ SCREENING TEST ] FOR MUCOPOLYSACCHARIDOSIS

ACID ALBUMIN (+)

[ SCREENING TEST ] FOR MUCOPOLYSACCHARIDOSIS

CETYLTRIMETHYLAMMONIUMBROMIDE (CTAB) TEST = ?

[ SCREENING TEST ] FOR MUCOPOLYSACCHARIDOSIS
MUCOPOLYSACCHARIDE (MPS) PAPER TEST = ?

A.k.a. Gargolysim or MPS Type 1

MPS accumulate in the CONREA of the eye

(+) SKELETAL ABNORMALITIES

(+) MENTAL RETARDATION

Sex-linked recessive, rarely seen in Females

(+) SKELETAL ABNORMALITIES

(+) MENTAL RETARDATION

(+) MENTAL RETARDATION

(-) Hypoxanthine guanine phosphoribosyltransferase

Uric acid in the blood and urine =“ORANGE SAND” in diaper

(-) GLUCOSE STRIP

(+) REDUCTION TEST

MEATURIA

presence of any CHO IN URINE

Inability to metabolize galactose to glucose

(-) Galactose-1-phosphate uridyl transferase (GALT)

(-) Galactokinase

(-) UDP-galactose-4-epimerase

Galactitol, galactonate, and galactose-1-phosphate

Associated w/ infant failure to thrive, liver dsds, cataracts, and severe mental retardation

DIABETES MELLITUS

seen during PREGNANCY and LACTATION

associated w/ PARENTERAL FEEDING