Tarry Stools: What Does It Mean?

Tarry stools are caused by bleeding or injury to the gastrointestinal tract. Although some link them to cancer, there are other diseases that can cause them.

Tarry stools refer to stool samples that are dark red or black in color. They are also often known as bloody stools or melena and are usually the result of bleeding or any type of injury in the gastrointestinal tract.

Not all cases of tarry stools indicate a serious problem, although its foul appearance and odor are alarming. In fact, stools sometimes darken from taking dark foods, iron supplements, or medications with Pepto-Bismol.

The attention and analysis of this fecal matter can be decisive for the diagnosis of some serious diseases. For this reason, it is important to know what they mean, what pathologies they are related to and how their treatment should be.

What does tarry stool mean? What are your causes?

To know what tarry stools mean, one must learn to differentiate the types of bleeding in the stool that can occur. In many cases the blood is hidden in the stool and can not be detected with the naked eye. Therefore, to determine it, a test known as the guaiac test may be necessary .

Types of bleeding in the stool

• Tarry stools: They are also called melena and are black colored stools with a foul odor whose main cause is usually upper gastrointestinal bleeding.

• Hematochezia: It is a combination of light and dark blood in the stools.

• Rectorrhagia : they appear with a light color and can be due to lower gastrointestinal bleeding or hemorrhoids.

Causes of tarry stools

The appearance of black or tarry stools usually indicates that the blood comes from the upper part of the gastrointestinal tract, that is, the region that includes the esophagus, stomach and the first part of the small intestine.

Blood usually takes on a tar-like appearance after being exposed to digestive juices. Some common triggers are:

• Trauma or infection.
• Bleeding ulcers in the stomach.
• Abnormal blood vessels (vascular malformation).
• Inflammation of the stomach lining or gastritis.
• Large, bulging veins in the intestine or esophagus (varicose veins).
• Interruption of the blood supply to part of the intestines (intestinal ischemia).
• Tears in the esophagus due to very strong vomiting ( Mallory-Weiss tear  ).

It is worth mentioning that there are other factors that can stain the stool black. For example, iron supplements and bismuth-based medications can cause it. In addition, they are sometimes the product of ingesting black licorice or blueberries. In these cases the doctor must examine the stool with a chemical to rule out blood.

Diagnosis

The detection of blood in the stool is a reason for urgent medical consultation. Since it can indicate a serious illness, it is essential to receive an accurate and timely diagnosis. The doctor will begin with a physical examination and a series of questions to complete the medical history.

Then, to determine if there is any obstruction or abnormality that may be causing a gastrointestinal bleeding, you may suggest other complementary diagnostic tests. The ones that are often used are the following:

• Stool culture.
• Colonoscopies.
• Magnetic resonances (RM).
• Barium ingestion studies.
• Esophagogastroduodenoscopy or EGD.
• Complete blood count (hemogram).
• Leukocyte formula and coagulation studies.
• X-rays and computed tomography (CT).
• Tests to check for Helicobacter pylori infection.

Treatment for tarry stools

Treatment for tarry stools varies depending on the pathology or injury that causes them. According to information from the American Cancer Society (ACS), patients suffering from hemorrhoids can reduce bleeding by using laxatives recommended by the doctor.

Other measures used in this type of cases are sitz baths and corticosteroid-based ointments. When bleeding is due to bleeding ulcers, the doctor may prescribe antacid medications. If caused by inflammatory bowel conditions or infections, treatment may include antibiotics and immunosuppressants.

Since in some cases the bleeding does not stop spontaneously, surgical intervention is sometimes necessary. This measurement is usually taken for venous obstructions or abnormalities in the system. A blood transfusion may also be suggested in case of heavy bleeding.

The presence of blood in the stool is sometimes caused by polyps in the colon. These almost always indicate precancerous conditions or cancer in patients. If this type of diagnosis is confirmed, the professional suggests surgery to remove the polyps, or chemotherapy and radiotherapy, if necessary.