Non-invasive test for assessing bacterial overgrowth of the small intestine

• US 6,264,913 B1
• Filed: 04/16/1999
• Issued: 07/24/2001
• Est. Priority Date: 05/08/1998
• Status: Expired due to Fees

• Current Assignee: Metabolic Solutions Incorporated
• Original Assignee: Metabolic Solutions Incorporated
• Inventors: Wagner, David A.
• Primary Examiner(s): Dudash, Diana
• Assistant Examiner(s): SHARAREH, SHAHNAM J
• Application Number:
  US09/293,191
• Time in Patent Office: 830 Days
• Field of Search: 424/1.13, 424/1.33, 424/1.81, 424/1.65, 424/1.37, 435/29, 435/34, 435/35, 435/39, 514/23, 514/24, 514/25
• US Class Current: 424/1.37
• CPC Class Codes: A61K 51/0491 Sugars, nucleosides, nucleotides, oligonucleotides, nucleic acids, e.g. DNA, RNA, nucleic acid aptamers
• CPC Class Codes: C12Q 1/04 Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor C12Q1/6897 takes precedence
• CPC Class Codes: C12Q 1/16 using radioactive material

Abstract

Provided herein is a novel breath test for assessing bacterial overgrowth. The test involves administration of a labeled sorbitol or sorbitol derivative to a subject and measurement of the label in breath and/or blood.

Claims

1. A method of assessing bacterial overgrowth in the small intestine of a subject comprising the steps of:

a. administering an amount of carbon-labeled sorbitol or sorbitol derivative to said subject, wherein said sorbitol derivative has the characteristics of not being readily absorbed by said subject and being metabolizable by bacteria;

b. collecting a specimnen from said subject;

c. measuring an amount of labeled carbon in said specimen to obtain a measured amount; and

d. comparing said measured amount with a positive standard and a negative standard to assess bacterial overgrowth in said subject,

wherein said negative standard is an amount of expired labeled carbon in a control group without bacterial overgrowth, and wherein said positive standard is an amount of expired labeled carbon in a control group with bacterial overgrowth.

2. The method according to claim 1 wherein said carbon-labeled sorbitol or sorbitol derivative is selected from the group consisting of ¹⁴C sorbitol or sorbitol derivative and ¹³C sorbitol or sorbitol derivative, or mixtures thereof.

3. The method according to claim 1 wherein said carbon-labeled sorbitol is ¹³C sorbitol.

4. The method according to claim 1 wherein said carbon-labeled sorbitol or sorbitol derivative is labeled at the 1-position of sorbitol or the 1-position of the sorbitol derivative.

5. The method of claim 1 wherein said carbon-labeled sorbitol or sorbitol derivative comprises a plurality of labeled carbons.

6. The method according to claim 1 wherein said labeled carbon in said specimen is labeled carbon dioxide.

7. The method according to claim 6 wherein said labeled carbon dioxide in said specimen is ¹³C carbon dioxide.

8. The method according to claim 1 wherein said administering step comprises administering carbon-labeled sorbitol or sorbitol derivative in a pharmaceutically acceptable carrier.

9. The method according to claim 1 wherein said measuring comprises isotopic measurement of labeled carbon.

10. The method according to claim 9 wherein said measurement is selected from the group consisting of mass spectrometric measurement, laser measurement, infrared detection, nuclear magnetic resonance and liquid scintillation counting of labeled carbon.

11. The method according to claim 1 wherein said specimen is selected from the group consisting of breath or blood.

12. The method according to claim 11 wherein said blood specimen is selected from the group consisting of venous, capillary and arterial blood.

13. The method according to claim 12 wherein said blood specimen is treated with an acid prior to analysis of CO₂.

14. The method of claim 1, wherein said carbon-labeled sorbitol derivative is sorbitol.