Details for Patent: 7,736,622

Title:	Methods of diagnosing small intestinal bacterial overgrowth (SIBO) and SIBO-related conditions
Abstract:	Disclosed is a method of treating small intestinal bacterial overgrowth (SIBO) or a SIBO-caused condition in a human subject. SIBO-caused conditions include irritable bowel syndrome, fibromyalgia, chronic pelvic pain syndrome, chronic fatigue syndrome, depression, impaired mentation, impaired memory, halitosis, tinnitus, sugar craving, autism, attention deficit/hyperactivity disorder, drug sensitivity, an autoimmune disease, and Crohn's disease. Also disclosed are a method of screening for the abnormally likely presence of SIBO in a human subject and a method of detecting SIBO in a human subject. A method of determining the relative severity of SIBO or a SIBO-caused condition in a human subject, in whom small intestinal bacterial overgrowth (SIBO) has been detected, is also disclosed.
Inventor(s):	Lin; Henry C. (Manhattan Beach, CA), Pimentel; Mark (Los Angeles, CA)
Assignee:	Cedars-Sinai Medical Center (Los Angeles, CA)
Filing Date:	Feb 07, 2006
Application Number:	11/348,995
Claims:	1. A method of detecting small intestinal bacterial overgrowth (SIBO) in a human subject, comprising: detecting relative amounts of methane, hydrogen, and at least one sulfur-containing gas in a gas mixture exhaled by said human subject, after said human subject has ingested a controlled quantity of an isotope-labeled sugar, a sugar that is poorly digestible by a human or an isotope-labeled sugar that is poorly digestible by a human, said gas mixture being at least partially produced by the intestinal microflora of said human subject; and corroborating the relative amounts of methane, hydrogen, and at least one sulfur-containing gas with a presence or absence of SIBO, wherein an amount of methane, hydrogen, or at least one sulfur-containing gas that is above a normal range for a healthy human subject for the methane, hydrogen, and/or at least one sulfur-containing gas is corroborated with the presence of SIBO, an amount of methane and/or hydrogen that is less than an amount of the at least one sulfur-containing gas is corroborated with the presence of SIBO, an amount of methane, hydrogen, and at least one sulfur-containing gas that is below the normal range for a healthy human subject for methane, hydrogen, and at least one sulfur-containing gas is corroborated with the absence of SIBO, or an absence of methane, hydrogen, or at least one sulfur-containing gas is corroborated with the absence of SIBO. 2. The method of claim 1, wherein the isotope-labeled sugar, the sugar that is poorly digestible by a human, or the isotope-labeled sugar that is poorly digestible by a human is glucose, lactose, sucrose, lactulose or xylose. 3. The method of claim 1, wherein detecting the relative amounts of methane, hydrogen, and at least one sulfur-containing gas in the exhaled gas mixture is accomplished by gas chromatography and/or a radiation detection system. 4. The method of claim 1, wherein detecting the relative amounts of methane, hydrogen, and at least one sulfur-containing gas in the exhaled gas mixture is accomplished by mass spectrometry. 5. The method of claim 1, wherein detecting the relative amounts of methane, hydrogen, and at least one sulfur-containing gas in the exhaled gas mixture is accomplished using thin-layer chromatography, high pressure liquid chromatography, an electrochemical voltametric sensor, or a polarographic cell. 6. The method of claim 1, wherein the at least one sulfur-containing gas is hydrogen sulfide or a sulfhydryl compound. 7. The method of claim 1, wherein the at least one sulfur-containing gas is methanethiol, dimethylsulfide, dimethyl disulfide, an allyl methyl sulfide, an allyl methyl disulfide, an allyl disulfide, an allyl mercaptan, or a methylmercaptan. 8. A method of determining the relative severity of SIBO or a SIBO caused condition in a human subject in whom SIBO has been detected, comprising: detecting in the subject by suitable detection means, the presence of SIBO, or detecting with said means the absence of SIBO; and, if the presence of SIBO is detected in the subject, detecting in the subject by suitable detection means a relative level of intestinal permeability, abnormally high intestinal permeability indicating a relatively severe SIBO or SIBO-caused condition in the subject. 9. A kit for the diagnosis of SIBO or a SIBO-caused condition, comprising: at least one breath sampling container, a pre-measured amount of an isotope-labeled sugar, a sugar that is poorly digestible by a human or an isotope-labeled sugar that is poorly digestible by a human, and instructions for a user in detecting the presence or absence of SIBO by determining the relative amounts of methane, hydrogen, and at least one sulfur-containing gas in a gas mixture exhaled by said human subject, after said human subject has ingested a controlled quantity of the isotope-labeled sugar, the sugar that is poorly digestible by the human or the isotope-labeled sugar that is poorly digestible by the human. 10. The kit of claim 9, wherein the pre-measured isotope-labeled sugar, sugar that is poorly digestible by the human or isotope-labeled sugar that is poorly digestible by the human is glucose, lactose, sucrose, lactulose or xylose. 11. The kit of claim 9, further comprising standardized samples of methane, hydrogen, and at least one sulfur-containing gas. 12. The kit of claim 9, wherein the at least one sulfur-containing gas is hydrogen sulfide or a sulfhydryl compound. 13. The kit of claim 9, wherein the at least one sulfur-containing gas is methanethiol, dimethylsulfide, dimethyl disulfide, an allyl methyl sulfide, an allyl methyl disulfide, an allyl disulfide, an allyl mercaptan, or a methylmercaptan. 14. A method for detecting small intestinal bacterial overgrowth (SIBO) in a human subject by corroborating the relative amounts of methane, hydrogen, and at least one sulfur-containing gas with the presence or absence of SIBO, said method comprising: administering a controlled quantity of an isotope-labeled sugar, a sugar that is poorly digestible by a human or an isotope-labeled sugar that is poorly digestible by a human, to produce a gas mixture, said gas mixture being at least partially produced by the intestinal microflora of said human subject; and detecting the relative amounts of methane, hydrogen, and at least one sulfur-containing gas in said gas mixture exhaled by said human subject, wherein i) an amount of methane, hydrogen, or at least one sulfur-containing gas that is above a normal range for a healthy human subject for the methane, hydrogen, and/or at least one sulfur-containing gas is corroborated with the presence of SIBO; ii) an amount of methane and/or hydrogen that is less than an amount of the at least one sulfur-containing gas is corroborated with the presence of SIBO; iii) an amount of methane, hydrogen, and at least one sulfur-containing gas that is below the normal range for a healthy human subject for methane, hydrogen, and at least one sulfur-containing gas is corroborated with the absence of SIBO; or iv) an absence of methane, hydrogen, or at least one sulfur-containing gas is corroborated with the absence of SIBO. 15. The method of claim 14, wherein the isotope-labeled sugar, the sugar that is poorly digestible by a human, or the isotope-labeled sugar that is poorly digestible by a human is glucose, lactose, sucrose, lactulose or xylose. 16. The method of claim 14, wherein detecting the relative amounts of methane, hydrogen, and at least one sulfur-containing gas in the exhaled gas mixture is accomplished by gas chromatography and/or a radiation detection system. 17. The method of claim 14, wherein detecting the relative amounts of methane, hydrogen, and at least one sulfur-containing gas in the exhaled gas mixture is accomplished by mass spectrometry. 18. The method of claim 14, wherein detecting the relative amounts of methane, hydrogen, and at least one sulfur-containing gas in the exhaled gas mixture is accomplished using thin-layer chromatography, high pressure liquid chromatography, an electrochemical voltametric sensor, or a polarographic cell. 19. The method of claim 14, wherein the at least one sulfur-containing gas is hydrogen sulfide or a sulfhydryl compound. 20. The method of claim 14, wherein the at least one sulfur-containing gas is methanethiol, dimethylsulfide, dimethyl disulfide, an allyl methyl sulfide, an allyl methyl disulfide, an allyl disulfide, an allyl mercaptan, or a methylmercaptan.