Colonic Tissue Biopsy

A tissue culture microscope in the hospital laboratory is a very useful tool for all medical technologists and pathologists alike. This equipment is used very specifically for the examination of biopsies or tissues taken from a patient to determine if there are any anomalies that may signify the presence of malignant disease.

This article explains the use of a tissue culture microscope in a colonic tissue biopsy. The specimen or tissue is extracted from the patient’s bowel through what is called a colonoscopy, which is a procedure where a fiber-optic tube is inserted via the rectum and advanced slowly into the large intestine. The tip of this flexible tube has a light source and a tiny camera for visualization of the inner lining of the colon. Specific preparations are performed on the patient before the procedure, like health teachings and cleansing enemas. The patient is informed that there will be some discomfort during the procedure. A consent form needs to be signed by the patient since this method is invasive. If the patient is anxious prior to the procedure, a sedative or a relaxant may be administered.

Once the specimen has been obtained, it is sent to the laboratory of the hospital and placed in a special culture medium to grow. They are examined under a tissue culture microscope everyday after being incubated in varying temperatures. Microorganisms are identified and a diagnosis of the patient’s condition and recommendations for his or her treatment regimen is prepared.

A colonoscopy to obtain tissue culture is often the last alternative in trying to determine what ails the patient. Before a colonoscopy, the physician would have already exhausted diagnostic methods such as stool exams to resort to something as invasive as this. Apart from bacteria, colonic biopsy cultures also detect inflammatory bowel disease and colon cancer. Although the colon harbors bacteria that are “normal” in the system, the presence of other bacteria may be a cause for concern. Examples of these are salmonella, shigella and C. difficile. Parasites and viruses may also be detected using tissue culture methods. With the advent of more advanced tools and equipment like the tissue culture microscope and culture medium, other pathogenic organisms can be quickly identified and acted upon to prevent further spread of the disease and alleviate present symptoms.

Your physician may refer you to a gastroenterologist for the procedure. He or she must be able to answer all your queries about the procedures and reiterate the complications and risks that may result from the procedure, such as perforation of the bowel or bleeding. Although you may suffer some form of discomfort during and after the procedure, tissue culture methods are usually great diagnostic tools. They are often more accurate and more complete, so many things can be interpreted from the test as compared to other diagnostic exams like stool cultures. Your medication and treatment regimen will be tailored to meet your needs and aim for curative as well as palliative measures so you can obtain optimal health.

ORIGINAL TEXT:

A colonic tissue culture is a laboratory test performed on a specimen of colon (large intestine) tissue to isolate and identify organisms that may be causing certain infections, such as infectious diarrhea or parasitic and viral infections involving the colon.

The specimen is obtained by a colonoscopy. A colonoscopy is a procedure for viewing the interior lining of the colon using a colonoscope, a flexible fiber-optic tube about 1/2 inch thick.

Alternative Names

Colonic tissue culture

How the test is performed

A sample of colon tissue is obtained during a colonoscopy procedure using special instruments. The specimen is sent to the laboratory and placed in special culture media. The specimen is incubated at different temperatures and examined daily for the presence of microorganisms.

If certain microorganisms are detected, the laboratory will perform additional testing to further classify them. Susceptibility testing of the microorganisms will help find the best antimicrobial therapy.

How to prepare for the test

The preparation for the culture is the same as for a colonoscopy. The large intestine must be thoroughly cleansed. You may be asked to take laxatives or an enema the evening prior to the test. You will likely be instructed to be on a clear liquid diet for 24 to 48 hours before the test.

Before the colonoscopy is performed, the risks and benefits of the procedure will be explained to you, and you will be asked to sign a consent form. You may be given a sedative to help you relax as the colonoscopy is being done.

How the test will feel

You may feel the urge to defecate when the colonoscope is inserted.

Why the test is performed

The culture is performed to detect and identify certain infections which can affect the colon, especially when other tests such as stool culture have been unable to identify the underlying infection.

A colonoscopy may also be performed for other reasons, such as to identify certain forms of cancer or inflammatory bowel disease.

Normal Values

The colon has a high number of well-characterized bacteria termed “bowel flora.” The growth of these organisms in culture from a colonic biopsy does not mean there is an infection. These organisms are part of the normal flora present in the gut. What abnormal results mean

The detection of certain organisms in a colonic biopsy culture is considered abnormal. This includes certain bacteria, such as salmonella, shigella, Clostridium difficile, Mycobacterium tuberculosis and others. Parasites such as schistosomiasis and viruses such as cytomegalovirus are other examples of pathogenic organisms that may be detected.

What the risks are?

A colonoscopy is usually a safe procedure. However, it can cause a perforation (hole) in the large intestine, infection, and bleeding.

Special considerations

After the colonoscopy, you may have large amounts of flatulence (gas) caused by the air used to distend the colon.