Hydrogen breath test wiki

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Breath_test_instructions_2016

Green S pring S tation O ut-‐Patient C enter2360 W. J oppa R d. S uite 206, L utherville, M D 21093Kerrie H endren, R N B SN 410-‐583-‐2614HYDROGEN/METHANE B REATH T ESTSWhat is a BREATH TEST? Information for physicians and patients. (H2. Hydrogen and CH4. Methane)Hydrogen and/or Methane gas in the body are produced from intestinal bacteria. Bacteria, normally in the large intestine, produce hydrogen or methane through fermentation of carbohydrates. Substrates containing these carbohydrates, like Lactulose, is given orally to test for small intestinal bacterial presence. Some of the hydrogen or methane produced from the bacterial fermentation causes bloating, abdominal discomfort or diarrhea. The gases are absorbed by the intestinal mucosa and enter the vasculature and transported to the lungs. The gases are then exhaled through normal breathing. These are collected in a bag for immediate analysis.In Small Intestinal Bacterial Overgrowth (SIBO), bacteria exist in the small intestine. Lactulose, when used as the challenge dose, is poorly absorbed in the gastrointestinal tract making it the perfect substrate to test for bacterial overgrowth throughout the length of the small bowel (21 feet).NOTE: If lactose or fructose is given as substrate, bacteria compete with the natural digestive process and metabolize the sugar before it is absorbed and may produce an early rise in breath hydrogen. Dedicated intolerance testing for these sugars are performed separately.In Lactose and Fructose intolerance, the individual has a deficiency in the enzymes needed for its absorption. Normally, it is broken down in the small intestine, absorbed, and very little lactose or fructose reach the large intestine. If it reaches the colon in its raw form, it is metabolized by colonic bacteria producing a large amount of gas which can be measured distally in the breath sample. (Positive Intolerance Test).• Have your physician call Scheduling at 410.933.7495 to order the test.The Guidelines below are to be followed for ALL Hydrogen/Methane Breath Tests**12 HOURS BEFORE YOU START YOUR BREATH TEST, YOU SHOULD FAST. THIS MEANS DO NOT EAT OR DRINK ANYTHING OTHER THAN WATER.•Please wait 28 days to do the test after your last dose after your last dose of antibiotic therapy*, bismuth products, antimicrobial herbals* (i.e. berberine, oregano oil) or probiotics before the test •Please wait 14 days to do the breath test after bowel purgatives (i.e. for colonoscopy) or barium radiography.•Please wait 7 days after your last dose if you are taking Laxatives•Please wait 2 days after your last dose if you are taking Motility agents (i.e. Metoclopromide, Loperamide)•No smoking, including second-hand smoke, for at least 1 hour before or at any time during the breath test.•No sleeping or vigorous exercise for at least 1 hour before or any time during the breath test.•No eating or drinking anything at all during the breath test.* not for small intestine bacterial overgrowth since practitioners often test for efficacy of antibimicrobials during or just after the conclusion of therapyThe day before your test, please limit your diet.A low-residue diet that minimizes nonabsorbable carbohydrates (starches and sugars) is strongly recommended. Here are examples of foods that you CAN eat:•Baked or broiled chicken, fish or turkey. (salt and pepper only)•White bread only.•Plain steamed white rice.•Eggs•Clear chicken or beef broth.•Drink water, non-flavored black coffee, or tea.AVOID foods like:•Pasta, whole grain products, bran, high fiber cereals, granola, ect.•Fruit juices, applesauce, apricots, bananas, cantaloupe, canned fruit cocktail, grapes, honeydew melon, peaches, watermelon. Raw and dried fruits likes raisins and berries.•Vegetable juices, potatoes, alfalfa sprouts, beets, green/yellow beans, carrots, celery, cucumber, eggplant, lettuce, mushrooms, green/red peppers, squash, zucchini, broccoli, cauliflower, brussels sprouts, cabbage, kale, swiss chard, beans, lentils, corn, etc.•All nuts, seeds and beans, as well as foods that may contain seeds•Milk, cheese, ice cream, yogurt, butter• On the day of your study, report to Room 205 30 minutes before to register.This test will take at least 3 hours or longer. We have magazines for your reading enjoyment, or if you prefer, enjoy a movie while the test is in progress. Don’t hesitate to ask questions during the procedure。

氢呼气试验 (2)

氢呼气试验（HBT）图1. 氢/甲烷呼气试验基本原理氢呼气试验（hydrogen breath tests）指测定口服某种化合物后呼气中的氢气（hydrogen）浓度变化而诊断胃肠疾病的一类检验方法。

仪器条件许可时，除了氢气还同时作甲烷(methane)浓度测定，故试验有时也称为氢/甲烷呼气试验。

我院目前常规开展的项目有：1.葡萄糖氢呼气试验诊断小肠细菌过生长; 2. 乳果糖氢呼气试验测定口-盲肠通过时间，也可同时诊断小肠细菌过生长。

人和哺乳动物细胞代谢不产生氢气和甲烷，呼气中的氢气和甲烷来源于机体细菌对碳水化合物的发酵。

大肠是身体含细菌最多的地方，而胃和小肠的细菌量是很少的。

所以，餐后一段时间出现的呼气氢和甲烷浓度上升显然就是大肠细菌对食物残渣碳水化合物的发酵的结果。

经过一段时间的禁食，残渣中的可分解碳水化合物耗尽，呼气氢气和甲烷浓度将回复到大气水平。

葡萄糖是一种极易被小肠迅速完全吸收的碳水化合物。

因此，健康人口服一定剂量的葡萄糖后不会出现呼气氢气和甲烷浓度上升的现象，因为几乎没有多余的葡萄糖进入大肠。

相反，小肠细菌过生长的病人，口服的葡萄糖在被小肠吸收的同时也被过量的小肠细菌分解产气。

乳果糖是一种不能消化吸收的人工合成碳水合物。

因此，口服一定剂量的乳果糖后将会出现呼气氢气和甲烷浓度上升的现象，从口服起到呼气氢气和甲烷浓度上升的时间便是药物从口到大肠起点盲肠的运行时间，简称口-盲通过时间，它大致反映了小肠的动力状态。

如果有小肠细菌过生长的存在，口服的乳果糖在到达大肠前就会提前被分解，结果出现两次产气高峰。

基本步骤除白开水外禁食禁饮12h以上采集0时气样口服试验糖餐再次采集气样测定报告注意事项1．严格空腹和饮食控制耗尽食物残渣中碳水化合物，让呼气氢气和甲烷浓度保持在大气水平是氢呼气试验的前提条件。

试验前一天的饮食以清淡易消化为宜，晚餐必须在8点前结束、只能喝白稀饭，餐后禁止白开水以外的一切食物或饮料，空腹时间一定要超过12小时！2．严禁吸烟烟草燃烧产生大量的氢气，吸烟者在试验前至少要禁烟一小时。

Prepare

Regional LaboratoryHYDROGEN BREATH TESTSLACTOSE INTOLERANCE AND BACTERIAL OVERGROWTHPATIENT PREPARATION, PRECONDITIONS,AND COLLECTION PROCEDURESSCHEDULING:The Lactose intolerance and Bacterial overgrowth hydrogen breath tests must be scheduled in advance. Please call (616) 267-2660 to schedule these tests. The Butterworth Hospital Outpatient Laboratory location is the only Spectrum Health site that routinely collects specimens for the hydrogen breath tests. The test is available Monday through Friday with two appointments daily, each lasting up to three hours. PATIENT PREPARATIONS INSTRUCTIONS AND PRECONDITIONS:Only a properly prepared patient should have a hydrogen breath test performed. Incorrectly prepared patients may have conditions present that can affect the outcome of the test. Therefore the following instructions should be followed before testing:1. The patient should be instructed not to eat bran, high fiber cereals or other hard to digest foods likebeans the day before the test.2. The patient should fast for 12 hours prior to the test, with only water to drink.3. The patient should not smoke for at least one hour prior to or during the test.4. The patient should not vigorously exercise, smoke, or sleep for at least one hour prior to testing orduring the test.5. Ask the patient about any recent antibiotic therapy. Antibiotics SHOULD NOT be prescribed for atleast two weeks before testing.SPECIMEN COLLECTION:Improper specimen collection can adversely affect the outcome of the test. Specimen collection should only be performed by staff with experience in proper specimen collection procedures.Hydrogen Breath Test 1。

Hydrogen Breath Test-4patient

How does hydrogen breath testing work?The bacteria in the colon, including the anaerobic bacteria, are able to digest and use sugars and carbohydrates as food. When the anaerobic bacteria digest sugars and carbohydrates, they convert some of the sugars and carbohydrates into gases, most commonly hydrogen. They also mayproduce and release into the colon other substances, for example, chemicals that cause the colon to secrete water and cause diarrhea.As previously discussed, some of the hydrogen gas is absorbed by the colon into the blood and is eliminated in the breath where it can be measured. As long as little sugar or carbohydrate reaches the colon, the small amounts of gas and other substances that are produced do not cause a problem. When larger amounts of sugar or carbohydrate reach the colon because they are not digested and absorbed in the small intestine, larger amounts of gas and substances are formed in the colon.For example, if an individual digests and absorbs the sugar in milk (lactose) normally, then none of the lactose that is given for the lactose hydrogen breath test reaches the colon, and no increase in the concentration of hydrogen in the breath is seen during the breath test. On the other hand, if the individual does not digest and absorb the lactose completely, that is, he or she is lactose intolerant, the lactose travels through the small intestine and enters the colon where the bacteria digest it and produce hydrogen. An increase in hydrogen in the breath then is seen. Other sugars for which poor digestion can be diagnosed by breath testing include sucrose and fructose (found in corn syrup), and sorbitol (a sugar that is used as a low-calorie sweetener).There are ways other than abnormal digestion of dietary sugars by which the bacteria can cause problems. Unlike in the colon, the number of hydrogen-producing, anaerobic bacteria in the small intestine is small. If, however, large numbers of hydrogen-producing bacteria move into the small intestine from the colon, a condition called bacterial overgrowth of the small bowel, the bacteria may digest the sugars and carbohydrates before the small bowel has had a chance to digest and absorb them and produce large amounts of hydrogen.Finally, if individuals have abnormally rapid passage of food through the small intestine, there may not be enough time for the small intestine to digest and absorb sugars and carbohydrates. This results in the entry of larger amounts of sugar and carbohydrate into the colon where the bacteria can digest and convert them to gas.To diagnose bacterial overgrowth and rapid transit through the small intestine, a sugar that is not digested and absorbed by man, such as lactulose, usually is used for the test. In the case of rapid passage through the small intestine, the sugar passes quickly through the small intestine and intothe colon so that hydrogen is found in the breath very soon after ingestion of the sugar. In the caseof bacterial overgrowth, production of hydrogen occurs twice during the test. Once as the sugar passes the bacteria in the small intestine and again when the sugar enters the colon.How is hydrogen breath testing performed?Prior to hydrogen breath testing, the patient fasts for at least 12 hours. At the start of the test, the patient blows into and fills a balloon with a breath of air. The concentration of hydrogen is measured in a sample of breath removed from the balloon. The patient then ingests a small amount of the testsugar (lactose, sucrose, sorbitol, fructose, lactulose, etc. depending on the purpose of the test). Additional samples of breath are collected and analyzed for hydrogen every 15 minutes for three and up to five hours.How are the results of hydrogen breath testing interpreted?The interpretation of the results of hydrogen breath testing depends on the sugar that is used for testing, and the pattern of hydrogen production after the sugar is ingested.After ingestion of test doses of the dietary sugars lactose, sucrose, fructose or sorbitol, any production of hydrogen means that there has been a problem with digestion or absorption of the test sugar and that some of the sugar has reached the colon.When rapid intestinal transit is present, the test dose of non-digestible lactulose reaches the colon more quickly than normally, and, therefore, hydrogen is produced by the colonic bacteria soon after the sugar is ingested.When bacterial overgrowth of the small bowel is present, ingestion of lactulose results in two separate periods during the test in which hydrogen is produced, an earlier period caused by the bacteria in the small intestine and a later one caused by the bacteria in the colon.What are the limitations of hydrogen breath testing?There are several limitations to hydrogen breath testing. For unclear reasons, testing for bacterial overgrowth of the small bowel with lactulose can diagnose only 60% of cases. (This insensitivity of the test may be due in part to the strict criteria that are used for interpreting a test as abnormal. Less strict criteria may diagnose overgrowth more often.) In addition, with bacterial overgrowth there may be an overlap of the early and later periods of hydrogen production that can be misinterpreted as a single period characteristic of rapid intestinal transit. Finally, some normal individuals may have slow transit through the small intestine making prolonged testing - up to 5 hours - necessary, and many individuals are unwilling to undergo such prolonged testing.Some individuals do not have bacteria that produce hydrogen, and in these individuals hydrogen breath testing is not possible. Most of these individuals have bacteria that produce a different gas, methane. (There also are individuals who produce both hydrogen and methane.) Methane can be measured in the breath just like hydrogen, and the production of methane can be used for diagnosis in the same way as hydrogen. There is much less experience with methane, however, and the production of methane is more complex than the production of hydrogen. Therefore, it is not clear if the pattern of methane production after ingestion of sugars can be interpreted in the same way as hydrogen production, particularly for the diagnosis of bacterial overgrowth.A pattern of hydrogen production that is typical for bacterial overgrowth does not necessarily mean that an individual's symptoms are caused by the overgrowth. For example, there may be anatomic abnormalities of the small intestine such as narrowing or functional abnormalities in the waythe muscle of the small intestine works. These abnormalities can cause symptoms of bloating, distention, pain, and diarrhea themselves, but they also can lead to bacterial overgrowth with its similar symptoms. Therefore, it may be an underlying abnormality that is responsible for the symptoms and not the bacterial overgrowth. The only way to differentiate between the two causes of symptoms-an underlying problem or bacterial overgrowth - is to treat and eradicate the bacteria. If the symptoms disappear, then it is more likely that it is the overgrowth rather than the underlying abnormality that is responsible for the symptoms.Any condition that results in the delivery of undigested or unabsorbed food to the colon may result in abnormal breath tests when dietary sugars are used for testing. Both pancreatic insufficiencyand celiac sprue can cause abnormal breath tests, in the former instance becausepancreatic enzymes that are necessary for the digestion of carbohydrates are missing, and in the latter instance because the lining of the small intestine is destroyed, and digested food cannot be absorbed. It may be necessary to exclude these causes of abnormal breath tests by additional tests-pancreatic function tests and small intestinal biopsy.Are there other ways in which hydrogen breath testing can be used?Antibiotics are used for treating bacterial overgrowth of the small bowel; however, anyone antibiotic may be effective at eliminating the overgrowing bacteria only 50%-60% of the time. Therefore, if symptoms do not disappear in an individual following treatment with antibiotics, it may be useful to repeat the breath test to determine if the antibiotics have eliminated the bacteria. If not, a different antibiotic or non-antibiotic treatment can be tried.What are the side effects of hydrogen breath testing?The side effects of hydrogen breath testing are exactly what one would expect to see in individuals who poorly digest and absorb sugars and carbohydrates, for example, bloating, distention, pain, and diarrhea. When lactulose is used these symptoms are unlikely to occur or are mild because the dose of lactulose used for testing is small.What are the alternatives to hydrogen breath testing?For diagnosing lactose intolerance, an alternative procedure to breath testing requires blood samples to be taken after the ingestion of lactose. If the digestion and absorption of lactose is normal, the levels of glucose in the blood should rise. The elevation of blood glucose occurs because the lactose is broken down into its two component sugars, galactose and glucose, as it is absorbed into the blood. A second alternative is to give a dose of lactose (or other dietary sugar) and observe an individual for symptoms. If the individual is intolerant, bloating, distention, pain, flatulence,。

Hydrogen_Breath_Test

Hydrogen Breath TestWhat is a hydrogen breath test?This is a test for bacterial overgrowth, or intolerances to lactose, fructose, or sucrose. Glucose is a sugar that will be broken down by bacteria if present in the small bowel with hydrogen or methane gas as a by-product. The breath sample will be analyzed for hydrogen or methane content to determine if you are able to properly break down the lactose, fructose, or sucrose, or if you have bacterial overgrowth.What can I expect from a hydrogen breath test?This test requires that you drink a solution of lactose, fructose, sucrose, or glucose in water. Lactose is the sugar found in milk and is normally broken down in the small bowel. Glucose is a sugar that will be broken down by bacteria if present in the small bowel with hydrogen as a by-product. Sucrose is a common sugar found in foods such as candy. After drinking the solution, you will be asked to breathe into a plastic bag. Breath samples are obtained every 15 minutes for adults, and every 30 minutes for children. The breath sample will be analyzed for hydrogen content to determine if you are able to properly break down the lactose or sucrose, or if you have bacterial overgrowth.The test is performed in the Gastrointestinal Physiology Laboratory of the Medical Procedures Unit.How do I prepare for a hydrogen breath test?Please follow these instructions to ensure a successful test.Two weeks before your test:o You must be off antibiotics and Pepto-Bismol™ for two (2) weeks.Two days before your test:o Eat a . The purpose of this diet is to avoid foods that may produce gas in the intestinal tract for two daysbefore your test, as this could cause inaccurate test results.milk/yogurt/icecream, rice milk; any aged orSample Menus:2 scrambled eggs and 1 bananasalad with grilled chicken, tomato, cucumber, carrots, feta, balsamic vinegar + olive oil dressing1 cup fruit (such as blueberries and strawberries), small handful ofpeanuts or almondsGrilled chicken, baked potato, ½ cup steamed broccoli1 cup popcornplain cheerios with lactose-free milk (such as Lactaid brand) or oatmeal with cinnamon and blueberriessandwich with turkey, cheese, lettuce, and tomato on gluten-free bread;plain potato chips or 1 orangebaby carrots and 1 cheese stickgrilled salmon with lemon, brown rice or quinoa, sautéed zucchini and yellow squash1 cup grapes∙The day before your test:o You should have .o, or until your examination is completed.o This includes any type of or∙ breath tests can be done anytime a colonoscopy prep;but not for four (4) weeks a colonoscopy prep, or any test thatrequires a bowel prep.∙Before starting the test you will be asked to rinse your mouth with mouthwash. This limits the effect of bacteria in your mouth on theresults.Can I take my medicine before a hydrogen breath test?Noncritical medicines, including over-the-counter medicines andsupplements should not be taken, unless your physician or nurse has advised you otherwise.If you are unable to keep your appointment, please call the Medical Procedures Unit at (734) 936-9250, option 1.Websites affiliated with the University of Michigan Health System: Your Digestive System and How it WorksDirections to the Medical Procedures Unit– Look for number 24 on the floor plan.Instructions for Patients with Diabetes Having Outpatient Tests (on insulin) Instructions for Patients with Diabetes Having Outpatient Tests (no insulin)Other related Websites:National Digestive Diseases Information Clearing House – Lactose Intolerance。

甲烷和氢呼气使用手册

甲烷和氢呼气使用手册屮烷和氢呼气试验解决了很多其它试验难以检查的项LI以及一些无法完成的检测盲区，譬如胰腺功能检查、小肠细菌过增长、肠道通过时间以及乳糖酶缺乏症, 都是其它检查方法都不能完成的“盲区”。

呼气检测方法是一种无创、无痛、准确、环保、快捷技术，具有广泛的临床应用价值。

检测询需要做好准备工作。

,禁食12小时,头天晚餐不吃不易消化的食物。

，晚饭后至测试前不喝含糖的饮料。

，清晨清洁口腔。

,不吸烟、不喝酒。

,避免剧烈运动。

空腹基础值的解释：H2 <10ppm:正常H2 10-20ppm:禁食不充分或晚餐进食不宜消化食物。

H2 >20ppm:考虑小肠细菌过度生长检测名称检测指标和LI的检测方法适应症乳糖呼气试验乳糖酶缺乏症1、先测空腹基础值乳糖酶缺乏症或不耐症小肠细菌过度生长2、口服乳糖，lg/Kg体重，各种功能性肠病总量不超过25呂慢性腹泻或慢性肠炎口盲通过时间3、每30分钟至60分钟采气肠道预激综合症的诊断一次胃肠或肝胆外科手术后肠道功能恢复的（如不考虑小肠细菌过度生评估。

长，可以每60分钟取气一次）检测名称检测指标和LI的检测方法适应症乳果糖呼气试验小肠细菌过度生长1、先测空腹基础值慢性腹泻或慢性结肠炎2、口服乳果糖0. 5g/Kg体口盲通过时间功能性肠病重，总量不超过10g回盲瓣功能不良消化不良综合症溶于180-250ml水慢性肝病或肝硬化3、每20分钟至30分钟采气糖尿病患者的胃肠动力异常一次慢性便秘阳性:2小时内H2上亚健康状态升〉12ppm乳糖酶缺乏症或不耐症各种功能性肠病慢性腹泻或慢性肠炎肠道预激综合症的诊断胃肠或肝胆外科手术后肠道功能恢复的评估。

检测名称检测指标和LI的检测方法适应症葡萄糖呼气试验小肠细菌过度生长1、先测空腹基础值2、口服葡萄糖，lg/Kg体重，总量不超过100g溶于250ml水3、每20分钟至30分钟采气一次阳性:2小时内H2上升＞12ppm检测名称检测指标和II的检测方法适应症果糖呼气试验果糖不耐受检测名称检测指标和LI的检测方法适应症蔗糖呼气试验蔗糖不耐受检测名称检测指标和LI的检测方法适应症山梨醇呼气试验山梨醇不耐受检测名称检测指标和□的检测方法适应症支链淀粉呼气试胰腺外分泌功能评估胰腺炎后胰腺功能损伤验糖尿病患者的病因和预后检测名称检测指标和LI的检测方法适应症金属镁呼气试验胃酸含量该技术的应用范围涵盖40%-60%的胃肠疾病，消化科、儿科、体检中心、内分泌科、胃肠及肝胆外科等临床科室都可开展。

呼吸注水试验操作流程

呼吸注水试验操作流程英文回答：To conduct the water immersion test, also known as the breath-holding test, the following steps can be followed:1. Preparation: Fill a container with water, ensuring there is enough water to completely submerge the subject's face. Make sure the water is at a comfortable temperature, neither too hot nor too cold.2. Explanation: Explain the procedure to the subject, ensuring they understand the purpose of the test and what is expected of them. Assure them that they can stop the test at any time if they feel uncomfortable or unable to continue.3. Demonstration: Show the subject how to perform the test correctly. Take a deep breath, close your mouth and eyes, and submerge your face into the water. Hold yourbreath for as long as you can, and then resurface when you need to breathe.4. Test: Ask the subject to take a deep breath and hold it. Then, instruct them to submerge their face into the water, making sure their mouth and nose are completely covered by the water. Start a timer to record the durationof the breath-holding.5. Monitoring: Observe the subject closely during the test. Look for signs of distress, discomfort, or any irregularities in their breathing pattern. If the subject experiences any difficulties, immediately instruct them to resurface and breathe normally.6. Recording: Note down the duration of the breath-holding, as well as any observations or remarks about the subject's performance during the test. This informationwill be helpful for analysis and comparison in future tests.7. Repeat: If necessary, repeat the test multiple times to obtain consistent results. Allow sufficient rest periodsbetween each trial to prevent fatigue and ensure accurate measurements.8. Debriefing: After the test, discuss the results with the subject. Provide feedback on their performance andoffer any suggestions or recommendations for improvement if needed.中文回答：进行呼吸注水试验，也称为憋气试验，可以按照以下步骤进行：1. 准备，准备一个容器，装满水，确保水足够多，能够完全浸没被试者的脸部。

methane-breath-testing

Glucose Hydrogen/Methane Breath TestingEndoscopy SuitePatient InformationWhat is a breath test?A glucose hydrogen breath test is used to make several diagnoses including lactose intolerance, carbohydrate malabsorption and small bowel bacterial overgrowth.After giving you a sugary-tasting drink, we will ask you to blow (exhale) into a small bag and measure the gases in your breath every 20 minutes until the test has been completed. Please allow 3 hours to be at the hospital.Why am I having a breath test?If the working of your digestive tract has been changed by surgery, chemotherapy, radiotherapy or other conditions, you may have symptoms such as watery loose stool, a need to rush to the lavatory, wind and bloating.If certain gases (hydrogen and methane) in your breath are abnormally high, it will help us to establish whether your symptoms are due to speciﬁ c foods in your diet or whether you have germs in the small bowel where there should not be any.In small bowel bacterial overgrowth, the test is used to try and detect the presence of germs in the small bowel.What preparation will I need for my breath test?You will be asked to change your diet (as outlined in this leaﬂ et) so that any breath test measurements recorded are accurate.It is important that you follow the instructions below very carefully. If these are not followed, your procedure may have to be cancelled.If any of the following apply to you, please contact the endoscopy suite a few days prior to your appointment (contact details on last page):•You have any concerns/queries•You have diabetesYou are taking chemotherapy drugs••You are taking anti-epileptic drugs•You are taking a medication which is taken daily at a set time You are due to undergo a gastroscopy and/or colonoscopy on •the same day as the breath test procedure24 hours before the testFoods from the following list are allowed to be eaten and does not inﬂ uence the test result:•Red meat•Fish eg. white ﬁ sh, shellﬁ sh, tuna, salmon,•Chicken•Tofu, QuornEggs – scrambled, boiled, fried, poached••Cheese – all typesMilk, natural yoghurt, ice cream••White: bread / rolls / croissants / chapattis/ rotis / naan /pitta bread / pastry•White pasta or rice•Rice crispies, cornﬂ akes, congee•Rich tea biscuits/other plain biscuits•Oil, butter, margarine, ghee•Potato (no skin) eg. boiled, mashed, roast, crisps•Tea/Coﬀ ee with a splash of milk & no sugar. Herbal tea. •Salt / pepper / herbs / spices / marmite / mayonnaise /mustard / salad dressing•Sugar free chewing gumThe following food does inﬂ uence the test result and should NOT be consumed for 24 hours before the test:•Canned drinks, carbonated drinks & fruit juices•Alcohol•Fruit (including fresh, tinned, stewed, dried, or preserved)•ALL vegetables except potatoes (no skin)•Sweets, chocolateSugar••Marmalade, jam, honey, chocolate spread, peanut butter •Tomato Ketchup, brown sauce, pickle, chutney, chilli sauce •Wholegrain cereals eg. weetabix, all bran, bran ﬂ akes,muesli•Brown rice or pastaWholemeal: bread / rolls / chapattis/ rotis / naan••Lentils, pulses•Nuts12 hours before the test:•Please do not eat or drink anything except water for 12 hours before the test ie. if your test is at 8am, stop eating anddrinking after 8pm on the previous night.You are allowed to drink water at any time.••Take your evening medications as usual.On the morning of your test•Please clean your teeth. Avoid mouthwash unless it issugar free. Sugar free mouthwash will be provided at theendoscopy suite.•Unless told otherwise, DO NOT take your usual medication (as it may be sugar coated) before the test, however do bring ALL your usual medication with you to the hospital so you can take it after completion of the test.•Do not smoke for an hour before the test or during the test as it raises your hydrogen levels and causes a false positive result.What will happen when I come up for the breath test?•You will be asked to complete a questionnaire about yoursymptoms.•You will be asked to blow (exhale) into a bag for a baseline measurement.You will be given a small sweet liquid to drink.••You will then be asked to blow (exhale) in to a bag at speciﬁ c times until the test is completed.•You will be asked to write down any bowel symptoms you experience during the test.What happens afterwards?You may eat and drink as normal. You will be given a drink and a sandwich following the procedure and can take your usual medications.When will I know the results?The results will be sent to your GP and the consultant who referred you for the test. A follow up appointment will be arranged if required.Endoscopy Suite Contact DetailsThe working times of the Endoscopy Suite are 08.00 - 17.00 Monday to Friday: 0207 811 8328. If your call is unanswered, you can leave an answerphone message. Answerphone messages will be checked twice daily (Monday – Friday) and a member of the Endoscopy Suite will return your call as soon as possible.Outside of working hours, you can ring the main switchboard number: 0207 352 8171 and ask to speak to the Clinical Site Practitioner (bleep 022) at Chelsea.If you would like this information sheet in a diﬀ erent format, please contact the PALs oﬃ ce on 0800 783 7176 or talk to the clinical staﬀ responsible for your care.ReferencesThis booklet is evidence based wherever the appropriate evidence is available, and represents an accumulation of expert opinion and professional interpretation. Details of the references used in writing this booklet are available on request from:The Royal Marsden Help CentreFreephone: 0800 783 7176Email: patientcentre@No conﬂ icts of interest were declared in the production of this bookletPublished October 2012. Planned review October 2014© The Royal Marsden NHS Foundation Trust EU-1331-01Life demands excellenceRadiotherapy andChemotherapy ServicesF538021 & F538022。

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Hydrogen breath testA hydrogen breath test (or HBT) is used as a diagnostic tool for people with irritable bowel syndrome, and common food intolerances. The test is simple, non-invasive, and is performed after a short period of fasting (typically 8–12 hours). Even though the test is normally known as a "Hydrogen Breath Test" some physicians may also test for methane in addition to hydrogen. Many studies have shown that some patients (approximately 35% or more) do not produce hydrogen but actually produce methane. Some patients produce a combination of the two gases. Other patients, who are known as "Non-Responders", don't produce any gas; it has not yet been determined whether they may actually produce another gas. In addition to hydrogen and methane, some facilities alsoutilize carbon dioxide (CO2) in the patients' breath to determine if the breath samples that are being analyzed are not contaminated (either with room air or bronchial dead space air).Testing may be administered at hospitals, clinics, physician offices or if the physician/laboratory has the proper equipment and breath collection kit, patients can collect samples at home to then be mailed in for analysis.Conditions[edit]Tests vary from country to country, so the following information is provided as a rough guide to typical uses of the hydrogen breath test:Fructose malabsorption– the patient takes a base reading of hydrogen levels in his/her breath. The patient is then given a small amount of fructose, and then required to take readings every 15, 30 or 60 minutes for two to three hours. The basis of the test is a failure to absorb the given sugar, which is then metabolized by bacteria that give off either hydrogen or methane. Therefore, the more gas that is produced, the less absorption has occurred. If the level of hydrogen rises above 20 ppm (parts per million) over the lowest preceding value within the test period, the patient is typically diagnosed as a fructose malabsorber. If the patient produces methane then the parts per million for the methane typically rises 12 ppm over the lowest preceding value to be considered positive. If the patient produces both hydrogen and methane then the values are typically added together and the mean of the numbers is used to determine positive results, usually 15 ppm over the lowest preceding value.Lactose malabsorption– the patient takes a base reading of hydrogen levels in his/her breath. The patient is then given a small amount of pure lactose(typically 20 to 25 g), and then required to take readings every 15, 30 or 60 minutes for two to three hours. If the level of hydrogen rises above 20 ppm (parts per million) over the lowest preceding value within the test period, the patient is typically diagnosed as a lactose malabsorber. If the patient produces methane then the parts per million for the methane typically rises 12 ppm over the lowest preceding value to be considered positive. If the patient produces both hydrogen and methane then the values are typically added together and the mean of the numbers is used to determine positive results, usually 15 ppm over the lowest preceding value. However, recent study suggest that testing may not correlate with any actual diagnosis.[1]Small Bowel Bacterial Overgrowth Syndrome (SBBOS) or Small Intestinal Bacterial Overgrowth (SIBO) – the patient is either given a challenge dose of glucose, also known as dextrose (75-100 grams), or lactulose (10 grams). A baseline breath sample is collected, and then additional samples are collected at 15 minute or 20 minute intervals for 3–5 hours. Positive diagnosis for a lactulose SIBO breath test – typically positive if the patient produces approximately 20 ppm of hydrogen and/or methane within the first two hours (indicates bacteria in the small intestine), followed by a much larger peak (colonic response). This is also known as a biphasic pattern. Lactulose is not absorbed by the digestive system and can help determine distal end bacterial overgrowth, which means the bacteria are lower in the lower intestine.The idea that a SIBO test should be several hours long and that distal overgrowth is important is wrong and is not supported by the scientific literature.[2][3][4][5][6][7] The optimal testing is 1 hour.[citation needed] Small intestinal bacterial overgrowth (SIBO) occurs as a result of excessive numbers of bacteria inhabiting the proximal small intestine. Bacterial concentrations greater than 105 organisms per milliliter is diagnostic for SIBO. We know bacteria are colonizing the proximal and not the distal small intestine for several reasons. First, the gold standard method for detection of SIBO is jejunal aspirates.[2][3][4][5][6][7] Intestinal fluid of the proximal intestine is sampled, not distal intestinal fluid. Secondly, the consequences of SIBO are the result of competition between bacteria and the human host for ingested nutrients in the intestine. Various functional consequences of bacterial infiltration cause enterocyte damage in the jejunum such as diminished disaccharidase activity, fat malabsorption, decreased amino acid transport and decreased vitamin B12absorption. Thus, detection of proximal bacterial overgrowth is critical.The SIBO breath test typically uses a 10 gram oral dose of lactulose for detection of proximal bacterial overgrowth. The best practice is to have breath samples collected at 20, 40, and 60 minutes after dosing. Since SIBO occurs in the proximal intestine, breath samples should be collected only within 1 hour after lactulose ingestion. This truly reflects proximal intestinal bacterial activity, not distal or colonic activity. The same argument is true if glucose is the substrate. Lactulose is a carbohydrate that is not absorbed by humans. Lactulose is well known to measure oro-cecal transit time.[2][3][4] The mean oro-cecal transit time in normal healthy individuals is 70 to 90 minutes.[5][6][7] By 90 minutes, at least 50% of individuals would have delivered the lactulose dose to the colon. Approximately 90 to 95% of individuals have colonic bacteria that can metabolize lactulose to hydrogen or methane gas. Thus, any SIBO breath test that collects longer than 60 minutes may be measuring colonic activity. Diagnostic criteria of 20 ppm hydrogen and/or methane changes within 90 or 120 minutes will have higher positive rates of SIBO but this will reflect colonic activity not jejunal metabolism. A one-hour SIBO breath test avoids false positive results by collecting breath up to 60 minutes.Positive diagnosis for a glucose SIBO breath test - glucose is absorbed by the digestive system so studies have shown it to be harder to diagnose distal end bacterial overgrowth since the glucose typically doesn't reach the colon before being absorbed. An increase of approximately 12 ppm or more in hydrogen and/or methane during the breath test could conclude bacterial overgrowth. Recent study indicates "The role of testing for SIBO in individuals with suspected IBS remains unclear."[8]The excess hydrogen or methane is assumed to be typically caused by an overgrowth of otherwise normal intestinal bacteria.[2][3][4][5][6][7]Other breath tests that can be taken include: Sucrose Intolerance, d-xylose and sorbitol. References[edit]1. Jump up^Bratten JR, Spanier J, Jones MP (April 2008). "Lactulose breath testing does notdiscriminate patients with irritable bowel syndrome from healthy controls.". The American Journal of Gastroenterology 103 (4): 958–63. doi:10.1111/j.1572-0241.2008.01785.x. PMID18371134.2. ^ Jump up to:a b c d Basilisco, G.; Risicato, R.; Bonazzi, P; Di Sario, A.; Portincasa, P. (2009). "H2-breath testing for evaluation of oro-caecal transit time".Aliment. Pharmacol. Ther. 29: 23–26.3. ^ Jump up to:a b c d Eisenmann, A.; Amann, A.; Said, M.; Datta, B.; Ledochowski, M. (2008)."Implementation and interpretation of hydrogen breath tests". J. Breath Res. 2: 1–9. doi:10.1088/1752-7155/2/4/046002.4. ^ Jump up to:a b c d Simren, M.; Statzer, P-O. (2006). "Use and abuse of hydrogen breathtests". Gut 55: 297–303. doi:10.1136/gut.2005.075127. PMC1856094.PMID16474100.5. ^ Jump up to:a b c d Hirakawa, M.; Lida, M.; Kohrogi, N.; et al. (1988). "Hydrogen breath testassessment of orocecal transit time: Comparison with barium meal study". Am. J. Gastroenterol. 83: 1361–1363.6. ^ Jump up to:a b c d Bond, J.H.; Levitt, M.D.; Prentiss, R. (1975). "Investigation of small bowel transittime in man utilizing pulmonary hydrogen (H2) measurements". J. Lab. Clin. Med. 85: 546–555.7. ^ Jump up to:a b c d Ghoshal, U. C. (2011). "How to interpret hydrogen breath tests". J.Neurogastroenterol. Motil. 17: 312–317. doi:10.5056/jnm.2011.17.3.312.8. Jump up^Ford, A. C.; Spiegel, B. M.; Talley, N. J.; Moayyedi, P. (August 12, 2009). "Small intestinalbacterial overgrowth in irritable bowel syndrome: systematic review and meta-analysis". Clin.Gastroenterol. Hepatol. 7 (12): 1279–86. doi:10.1016/j.cgh.2009.06.031. PMID19602448.。