How Is a CLO Test Conducted?

Submitted on March 27, 2012

Helicobacter pylori are bacteria that are considered to be the primary cause of peptic ulcers. The bacterium is found all over the world and can easily exist in a person without showing any symptoms. Once the bacterium has been able to colonize within its host, it lives between the surfaces of the epithelial cells and the overlying mucus gel layer. Studies have shown that once the bacterium has been allowed to settle in the system, it will remain for the lifespan of the individual. One of the most common conditions caused by peptic ulcers is known as peptic ulcers, which are simply small sores on the lining of the stomach or beginning of the small intestine, known as the duodenum. While the consumption of excessively spicy food can significantly aggravate the condition, it is not a direct cause of development. The condition is characterized by the prominence of a sharp pain whenever the digestive process is active. Some of the common symptoms experienced include a burning sensation in the belly or abdomen, which tends to get a lot worse when the stomach is empty. This will disappear as soon as the patient consumes some amount of food or liquid. The bacterium H. pylori is said to be contagious because of its tendency to run in families.

Before going into the details of the CLO test we first need to understand the functioning of certain aspects of the body and the diseases they are prone to. The digestive system in the human body is a complicated combination of various organs and systems that runs from the mouth to the anus. Food is chewed during consumption which allows for it to be swallowed. Once food reaches the stomach, the process of breakdown begins. Food is treated with strong acids and enzymes in the stomach which work to break down the food so that its nutrients can be easily absorbed in the intestines. The lining of the stomach is therefore supposed to be very strong so that it can withstand the highly acidic nature of some of the digestive juices used.

The term 'H pylori' is used for a type of bacteria that are found all across the world. Many people who host h pylori bacteria do not display any symptoms as this infestation is kept to a bare minimum. When the bacteria are able to multiply, they may break through the lining of the stomach. This will lead to the development of ulcers in the stomach. The ulcers develop when the exposed inner lining of the stomach is treated with digestive acids. This exposure can lead to painful symptoms for the patient as there will be direct contact between delicate tissue and powerful acid. In order to treat the patient for an infection by the h pylori bacteria, the doctor will first need to have a confirmed diagnosis that there is such an infestation in the body.

CLO Test For H Pylori & Endoscopy

The CLO test for h pylori is one method used to determine if the individual is suffering from an infection of this type of bacteria.

The CLO test endoscopy begins with a scope being inserted through the mouth into the stomach. This scope will be used to look around the stomach to see any obvious signs of damage in the form of ulcers. At this point, the CLO test biopsy can be conducted. A sample of the mucosa is taken and the scope is then removed. The CLO test rapid urease test is a variation of the test where the biopsy sample is placed in a medium containing urea. A marker is then used to determine if a chemical reaction has taken place to suggest the presence of the h pylori bacterium. This reaction takes place quickly and can then be used as a diagnosis of an infestation by the h pylori bacterium. When the CLO test is positive, it is a fairly reliable indicator that the individual is suffering from an infection of this bacterium. However, it should be noted that the CLO test, particularly CLO test rapid urease test is prone to producing false negative results. This is why other tests including a visual analysis during the endoscopy may be important. The reason that the rapid version of the test is used is that simple cases get diagnosed quickly and effectively. The treatment for an infestation of the bacterium can then begin. In many cases, doctors may prescribe treatment for the infestation even if the result is negative.

The CLO test involves an invasive endoscopy procedure. The test is therefore quite uncomfortable with patients often reporting irritation in their throat after the test. It is important for the individual to be fasting prior to the test so that the stomach is empty when the scope enters it. The patient may not even consume water for a couple of hours before the test begins. Apart from this, there is no major preparation required for the procedure. Regarding the side effects of the condition, in certain extreme cases, the patient will be admitted to the hospital for treatment. In all other cases, he or she may return home after the test is complete so that food can be consumed to nourish the body. Major and minor concers with regards to the cost of the procedure, the CLO test CPT code and so on could be discussed with the presiding doctor.

Reason Why It is Ordered?

CLO testing, also known as H. pylori testing, may be ordered when a patient is experiencing symptoms like a feeling of bloating or fullness, nausea, excessive belching or regurgitation and indigestion.


As with any type of blood test, a blood sample will be collected from a vein, usually at the back of the elbow. Before the drawing of the blood, the area where the vein is going to be punctured will be cleansed with the help of an alcohol scrub. A leather strap will then be fastened to the top of the arm in order to stop blood flow and cause the vein to swell up - increasing the level of accuracy for the doctor to puncture it. Once the needle is injected and the blood drawn, a cotton swab will be placed over the fresh wound and some amount of force exerted to speed up the healing process.


A positive clo test indicates that you have been infected with the organism. However, if the report comes back negative, this does not guarantee that you are not affected and, if the symptoms remain, the doctor may need to perform a more invasive for of diagnosis.