WHAT ‘S OB TEST?
A
fecal occult blood test (also called stool gaiac or heoccult test) is used to examine stool for traces of blood that can not be seen with the naked eye. This test can detect bleeding from almost anywhere in the digestive tract, and can come out positive for several conditions including colorectal cancer, esophagitis, gastritis, stomach cancer, ulcerative colitis and hemorrhoids. It can also be positive when asprin or other medications that irritate the digestive tract have been used.
WHY

Detect poor absorption of nutrients by the digestive tract (malabsorption syndrome). For this test, all stool is collected over a 72-hour period and then analyzed for the presence of fat and meat fibers. The presence of fat may indicate a malabsorption problem. This test is called a 72hour stool collection or quantitative fecal fat test.

WHAT IS THE PREPARATION?
At
least 72 hours before the test, the following dietary changes should be made: Avoid taking more than 250 mg/day of Vitamin C Avoid eating red meat (beef or lamb), including liver and processed meats Avoid eating raw fruits and vegetables, especially melons, radishes, turnips, and horseradish Any toilet bowel cleansers should be removed from the toilet, as they can affect the results of the test.
CONTENTS
An
examination of the physical characteristics of the stool for color, consistency, weight (volume), shape, odor, and the presence of mucus. The stool may be examined for hidden (occult) blood, fat, meat fibers, bile, white blood cells, and sugars called reducing substances. The pH of the stool also may be measured.
UPPER GI TRACT
(usually
black stools): Bleeding stomach or duodenal ulcer Gastritis Esophageal varices Mallory-Weiss tear (a tear in the esophagus from violent vomiting) Trauma or foreign body Bowel ischemia (a lack of proper blood flow to the intestines) Vascular malformation
LOWER GI TRACT
(usually
maroon or bright red, bloody stools): Hemorrhoids Anal fissures Diverticular bleeding 憩室出血 Intestinal infection (such as bacterial enterocolitis) Vascular malformation Inflammatory bowel disease Tumor Colon polyps or colon cancer Trauma or foreign body Bowel ischemia (a lack of proper blood flow to the intestines)
Stool analysis
WHY
Help
diagnose diseases of the digestive tract , liver, and pancreas. Certain enzymes (such as trypsin or elastase) may be evaluated in the stool to help determine how well the pancreas is functioning. determine the cause of symptoms affecting the digestive tract, including prolonged diarrhea（慢性腹泻）, bloody diarrhea, an increased amount of gas, nausea, vomiting, loss of appetite, bloating （胀气）, abdominal pain and cramping（痉 挛）, and fever.
BLACK TARRY STOOL
Be worried. Iron supplements can cause black stool, but the other, more alarming cause is digested BLOOD. Blood can turn the stool black, called "MELENA".. conditions like heartburn胃灼热, ulcers, cancer, any GI disease, as these may be the source of the bleeding.
FECAL OCCULT BLOOD TESTING
WHAT IS IT USED FOR?
A fecal occult blood test is often used to dectect colorectal cancer in it's early stages, which has no other signs or symptoms. Fecal occult blood tests are usually recommended annually for people over 50 years old. People at high risk for colorectal cancer because of family history or polyps should begin testing at age 40.
Help
WHY
Screen
for colorectal cancer by checking for hidden (occult) blood. Detect the presence of parasites, such as pinworms or Giardia lamblia. Detect and identify certain types of bacteria that can cause disease. This test is called a stool culture and can also be used to detect an infection caused by a fungus or virus.

NORMAL BACTERIAL FLORA
NORMAL BACTERIAL FLORA
NORMAL BACTERIAL FLORA
菌群失调
菌群失调
菌群失调
TESTING THE STOOL FOR OVA AND PARASITES
if a child has prolonged diarrhea or other intestinal symptoms. Sometimes, the doctor will collect 2 or more samples of stool to successfully identify parasites.

WHAT IS THE PREPARATION?
You should not test if you: Have active bleeding from a hemorrhoid or anal fissure Have blood in your urine Have taken asprin or other nonsteroidal antiinflammatory drugs (NSAIDs) in the past 7 days Are a woman having your menstral period or during the first three days after the end of your period