LACTOSE TOLERANCE

This test requires Lac-Tol solution be ingested by the patient after the baseline draw. Lac-Tol may be ordered from the Alverno Central Lab Purchasing Department (Item #320613).

Patient must be fasting 8 hours prior to beginning the test and remain fasting until test is completed.

A total of five (5) specimens will be drawn:

• Draw fasting
• Administer Lac-Tol solution
• Draw 30 minutes after consumption
• Draw 60 minutes after consumption
• Draw 90 minutes after consumption
• Draw 120 minutes after consumption

Glucose testing at fasting, 30 min, 60 min, 90 min, and 120 min

0.5 mL

Centrifuge gold tubes for complete separation of serum and cells. Sodium Fluoride tubes do not need to be centrifuged unless testing will not be completed within 24 hours.

• Blood test: add contents of two (2) packages of LacTest to 8oz of water. Thoroughly mix to suspend ingredients. Administer the LacTest solution according to body weight as indicated in the table below. For children less than 50 lbs, add water to the measured portion of LacTest solution to bring the final volume of liquid consumed to a total of 8oz.

Refrigerate

2-8°C up to 3 days

Hemolyzed samples will be rejected. Serum samples that are not separated from cells will be rejected.

M, Tu, W, Th, F, Sa, Su

65-115 mg/dL

The Lactose Tolerance test measures the functional activity of lactase, which is located in the mucosa of the small intestine. With normal lactase activity, lactose is converted to glucose and galactose by the enzymatic action of lactase. Lactase deficiency is characterized by flatulence, abdominal discomfort, bloating, or diarrhea after consumption of milk or milk products.

A patient with normal lactase activity will demonstrate a rise of at least 20 mg/dL from the fasting result. Lactase deficiency is defined as a maximum rise of LESS than 18 mg/dL from the fasting result.