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Test Code SQ LACTOZ, EPIC LAB2571 Lactose Tolerance, 3 Hour, Plasma

Methodology

Enzymatic Hexokinase

Performing Laboratory

Meriter Laboratories

Specimen Requirements

Patient Preparation:

1. Patient should be fasting (8 hour).

2. Patient should ingest no food containing milk for 48 hours prior to test.

 

Performance of Test:

1. Draw blood for a fasting glucose.

2. Give patient a standard dose of lactose (1 g/kg up to a maximum of 50 g in 200 mL of water).

Attention: A prescription is needed to obtain lactose from the pharmacy. For adults, fasting patient should be given 1 g of lactose per kg of body weight in 200 mL to 300 mL of water, and must be consumed in 5 to 10 minutes. If severe lactose deficiency is suspected, the dose should be lowered.

3. Patient is to ingest nothing except water during test.

4. Draw blood at 30 minutes, 1-, 2-, and 3-hours as necessary, timing from completion of ingestion of lactose.

 

 

Patient should bring their own prescription lactose to add to water to ingest for tolerance. 

 

Specimen Collection:

Specimen Type: Plasma

Container/Tube: Light-green top (lithium heparin gel)

Specimen Volume: 1 mL
Collection Instructions: Label tubes with patient’s full name (first and last) and date and actual time of draw.

Additional Information: A urine specimen is not required for this test.

Specimen Transport Temperature

Refrigerated

Reference Values

 

Lactose Intolerance Interpretation:

 

After patient is given a standard dose of lactose (1 g/kg up

to a maximum of 50 g in 200 ml of water), the blood test is

interpreted as follows:

 

Normal: >30 mg/dL rise in Glucose level within 2 hours of

drinking the lactose solution.

 

Inconclusive: 20-30 mg/dL rise in Glucose level within 2

hours of drinking the lactose solution.

 

Abnormal: <20 mg/dL rise in Glucose level within 2 hours of

drinking the lactose solution.

 

NOTE: An abnormal test should be followed by a glucose

tolerance test to rule out a problem with the body's ability

to absorb glucose.

Reporting Title

Lactose Tolerance, 3 Hour, Plasma

Day(s) Test Set Up

Monday through Friday

Test Classification and CPT Coding

82951-Lactose tolerance
82952 x 2-Lactose tolerance, additional specimens