Labs

Lab name

abbreviation

age

Normal values

Description

Alanine Aminotransferases

ALT

(SGPT)

Neonate/Infant

Adult, Male

Adult, Female

13-45 U/L

10-40 U/L

7-35 U/L

Marker for Hepatocellular injury

Cytosolic enzyme; highest concentration in Liver

More specific for liver injury than AST with longer half-life than AST

Aspartate Aminotransferase

AST

(SGOT)

Newborn

Infant

1-3yrs

4-6yrs

7-9yrs

10-11yrs

12-19yrs

25-75 U/L

15-60 U/L

20-60 U/L

15-50 U/L

15-40 U/L

10-60 U/L
15-45 U/L

Isoenzyme found in cytosol and mitochondria

Found in brain, heart, kidney, leukocytes, lung, muscle, pancreas, and RBCs

Elevation seen as early warning for rejection post transplant

Alkaline Phosphatase

Alk Phos

Infant

2-10yrs

Adolescent

Adult

150-420 U/L

100-320 U/L

100-390 U/L

30-120 U/L

Found in liver, kidney, bone, placenta, intestine, and WBCs

Marker for biliary epithelial damage, infiltration of biliary system, cirrhosis, rejection, or osteopenia from Vit D deficiency assoc w/ liver disease

*Elevated in bone growth, bone disease, transient hyperphos of infancy

Low Alk Phos suggests Zn deficiency or Wilsons disease

gamma-glutamyl transferase

GGT

Cord Blood

Preterm

0-3wks

3wk-3mo

3-12mo Male

3-12mo Female

1-15yr

Adult Male

Adult Female

19-270 U/L

56-233 U/L

0-130 U/L

4-120 U/L

5-65 U/L

5-35 U/L

0-23 U/L

11-50 U/L

7-32 U/L

Found in biliary epithelia and hepatocytes, kidney, pancreas, spleen, brain, breast, sm intestine

Differentiates liver disease from bone growth/bone Dz (Alk phos elevated with bone etiology but normal GGT)

Will be low/normal in PFIC 1&2, benign recurrent intrahepatic cholestasis, disorders of bile acid synthesis, panhypopit

Induced by certain anticonvulsants

Bilirubin, Direct

Dbili

Any Age

>1mg/dL

>20% of total

Bilirubin

Direct bilirubin may overestimate the actual conjugated bilirubin, as it includes both the conjugated bilirubin and bilirubin covalently bound to albumin (delta-bilirubin).

Indirect bilirubin may underestimate unconjugated bilirubin, as a portion of the unconjugated bilirubin reacts with diazosulfanilic acid, producing azobilirubin, which is measured as direct bilirubin.*

Prothrombin Time

Preterm Infant

Term Infant

1-17yrs

Adult

15.4

13.0

Measures the extrinsic pathway

Requires V, VII, X, Fibrinogen, and prothrombin

Vitamin K dependent

Prolonged in Liver Dz, Warfarin use, malabsorption, DIC

International Normalized Ratio

INR

All ages

Best measure of liver synthetic function

Standardized result of the PT test

Albumin

Alb

Cord

Newborn

1 day -1mo

1-3mo

4-6mo

7-12mo

13-24mo

25-36mo

3-5yrs

6-8yrs

9-11yrs

12-16yrs

Adult

2.2-4.0 g/dL

3.2-4.8

2.5-5.5

2.1-4.8

2.8-5.0

3.2-5.7

1.9-5.0

3.3-5.8

2.9-5.8

3.3-5.0

3.2-5.0

3.2-5.1

3.1-5.4

Synthesized only in the liver

Low in Urinary loss, GI loss, or starvation

Low in Chronic liver disease

Half life = 20 days

Prealbumin

Newborn

1-6mo

6mo-4yrs

4-6yrs

6-19yrs

7-39 mg/dL

8-34

2-36

12-30

12-42

Marker of adequate nutritional intake (unreliable in illness, inflammation, or catabolism)

Aka transthyretin - transports thyroxin and retinol binding protein

Half-life is 2 days (good indicator of short term nutritional status

Serum levels decreased during first 3-5 days of inflammatory illness

Decreased with albumin in exocrine pancreatic insufficiency

Modified nutritional index = (crp x fibrinogen)/(transferrin x prealbumin)

NMI >10 means higher mortality

Ammonia

Newborn

0-2wks

>1mo

Adult

90-150 ug/dL

79-129

29-70

0-50

Herparinized venous specimen on ice needs to be analyzed within 30min