🔅MELENA

– Melena is a medical term for black, tarry stools that are caused by bleeding in the upper gastrointestinal (GI) tract. The blood turns black as it is digested by enzymes and bacteria in the GI tract. Melena is different from hematochezia, which is the presence of fresh blood in the stools, usually from the lower GI tract.

CAUSES OF MELENA

– Melena can have various causes, such as:

1). Peptic ulcer disease: This is a condition where ulcers or sores develop in the stomach or duodenum (the first part of the small intestine). The ulcers can bleed and cause melena. Peptic ulcers can be caused by infection with H. pylori bacteria, chronic use of aspirin or NSAIDs, or excessive acid production.

2). Gastritis or esophagitis: These are inflammations of the stomach or esophagus, respectively, that can damage the lining of the GI tract and cause bleeding. Gastritis or esophagitis can be caused by GERD, alcohol, smoking, stress, or certain medications.

3). Erosive gastropathy: This is a condition where the stomach lining is eroded by various factors, such as stress, shock, burns, or critical illness. The erosion can lead to bleeding and melena.

4). Varices: These are swollen and fragile veins in the esophagus or stomach that can rupture and bleed. Varices are usually caused by portal hypertension, which is high blood pressure in the portal vein that carries blood from the digestive organs to the liver. Portal hypertension can be caused by liver disease, such as cirrhosis.

5). Mallory-Weiss tear: This is a tear or laceration in the lower esophagus that can occur due to violent vomiting, coughing, or straining. The tear can bleed and cause melena.

6). Tumors: These are abnormal growths of cells that can occur in the stomach, esophagus, or pancreas. Some tumors can be benign (non-cancerous), such as lipomas, while others can be malignant (cancerous), such as adenocarcinomas, squamous cell carcinomas, or carcinoid tumors. Tumors can bleed and cause melena.

7). Viral hemorrhagic fevers: These are rare and serious infections caused by certain viruses, such as Ebola, that can affect multiple organs and cause bleeding throughout the body. Melena can be a sign of viral hemorrhagic fever.

DIAGNOSIS OF MELENA

– Melena is diagnosed by examining the stool for blood and performing tests to determine the source and severity of the bleeding. Some of the tests include:

1). Fecal occult blood test (FOBT): This is a test that detects hidden blood in the stool. A positive FOBT indicates that there is bleeding somewhere in the GI tract, but it does not specify the location or cause.

2). Endoscopy: This is a procedure that uses a flexible tube with a camera and light to examine the inside of the GI tract. Endoscopy can identify the site and cause of the bleeding, such as ulcers, varices, or tumors. Endoscopy can also be used to treat some of the bleeding causes, such as by applying clips, bands, or injections to stop the bleeding.

3). Angiography: This is a procedure that uses contrast dye and X-rays to visualize the blood vessels in the GI tract. Angiography can locate the bleeding vessel and also be used to deliver embolization, which is a technique that blocks the bleeding vessel with a coil or a plug.

4). Capsule endoscopy: This is a procedure that uses a small, pill-sized camera that is swallowed by the patient. The camera travels through the GI tract and takes pictures that are transmitted to a recorder. Capsule endoscopy can be useful for examining the small intestine, which is difficult to reach by conventional endoscopy.

5). Blood tests: These are tests that measure the levels of hemoglobin, hematocrit, platelets, and coagulation factors in the blood. Blood tests can indicate the extent of blood loss and the risk of bleeding complications.

TREATMENT OF MELENA

– The treatment of melena depends on the cause and severity of the bleeding. Some of the treatment options include:

1) Medications: These are drugs that can reduce acid production, protect the stomach lining, or treat infections that cause bleeding. Some examples are proton pump inhibitors (PPIs), H2 blockers, antacids, sucralfate, or antibiotics.

2). Fluids and blood transfusions: These are interventions that can restore the fluid and blood volume that is lost due to bleeding. Fluids and blood transfusions can prevent dehydration, shock, and anemia.

3). Surgery: This is an option that can be used to remove or repair the source of bleeding, such as ulcers, tumors, or perforations. Surgery can also be used to create a bypass or shunt to reduce portal hypertension and prevent variceal bleeding.

4). Lifestyle changes: These are modifications that can help prevent or reduce the recurrence of bleeding. Some examples are avoiding alcohol, smoking, spicy foods, or NSAIDs, managing stress, and following a balanced diet.

COMPLICATIONS OF MELENA

– Melena is a serious symptom that requires prompt medical attention. If left untreated, melena can lead to complications such as:

i). Anemia: This is a condition where the red blood cells are low in number or function. Anemia can cause fatigue, weakness, shortness of breath, and pale skin.

ii). Hypovolemic shock: This is a condition where the blood pressure drops dangerously low due to blood loss. Hypovolemic shock can cause confusion, dizziness, fainting, and organ failure.

iii). Peritonitis: This is a condition where the abdominal cavity becomes inflamed and infected due to a perforation in the GI tract. Peritonitis can cause severe abdominal pain, fever, nausea, and vomiting.

iv). Sepsis: This is a condition where the body's immune system overreacts to an infection and causes widespread inflammation and organ damage. Sepsis can cause fever, chills, rapid breathing, and altered mental status.

#NOTE

~ Melena is a sign of bleeding in the upper GI tract that can have various causes and complications. Melena can be diagnosed and treated by various tests and procedures. Melena can be prevented or reduced by taking medications, making lifestyle changes, and seeking medical help when needed.

THE DIFFERENCE BETWEEN MELENA AND HEMATOCHEZIA

– Melena and hematochezia are both symptoms of gastrointestinal bleeding, but they have different causes and appearances. Melena is black, tarry, and sticky stool that results from bleeding in the upper gastrointestinal tract, such as the stomach or duodenum. Hematochezia is bright red blood that comes from the lower gastrointestinal tract, such as the colon or rectum.

• Melena usually indicates a more serious and chronic bleeding, while hematochezia usually indicates a less severe and acute bleeding. Both conditions require medical attention to diagnose and treat the underlying cause of the bleeding.

CAUSES OF HEMATOCHEZIA

– Hematochezia is the passage of fresh, bright red blood in the stool, usually indicating bleeding from the lower gastrointestinal (GI) tract. Some possible causes of hematochezia are:

i). Hemorrhoids: These are swollen veins in the lower rectum that can rupture and bleed, especially after straining during bowel movements.

ii). Diverticulosis: These are small pouches that form in the wall of the colon and can bleed if they become inflamed or infected.

iii). Inflammatory bowel disease (IBD): This is a group of conditions that cause chronic inflammation and ulcers in the GI tract, such as ulcerative colitis and Crohn's disease.

iv). Colorectal cancer: This is a malignant tumor that grows in the colon or rectum and can bleed or obstruct the bowel.

v). Angiodysplasia: These are abnormal blood vessels in the colon that can bleed spontaneously or due to low blood flow.

vi). Anal fissure: This is a small tear or crack in the skin of the anus that can bleed and cause pain during bowel movements causes.

vii). Polyps: These are benign growths that can develop in the colon or rectum and can bleed or become cancerous over time.

– These are some of the common causes of hematochezia, but there may be other less frequent or rare causes as well.