Gastrointestinal Bleeding: Symptoms, Types, Causes and Treatment

Gastrointestinal (GI) bleeding is a potentially life-threatening condition that can affect anyone, regardless of age or health status. It remains one of the most common causes of emergency hospital admissions worldwide, with significant impact on patient quality of life and healthcare systems. In this comprehensive article, we explore the key symptoms, classification types, underlying causes, and modern management strategies for GI bleeding, drawing on the latest clinical research and international guidelines.

Symptoms of Gastrointestinal Bleeding

Gastrointestinal bleeding can be alarming for patients and challenging for clinicians. Recognizing the warning signs early is critical for prompt diagnosis and effective treatment. Symptoms can range from subtle and barely noticeable to dramatic and life-threatening.

Symptom	Description	Typical Location	Source(s)
Hematemesis	Vomiting of blood (bright red or coffee-ground)	Upper GI tract	1 2 3 10
Melena	Black, tarry stools indicating digested blood	Usually Upper GI	1 2 12
Hematochezia	Passage of fresh red or maroon blood per rectum	Lower GI (can be brisk upper GI)	9 12
Lightheadedness	Feeling faint or dizzy, especially on standing	Any GI bleeding	1 14
Syncope	Fainting due to blood loss	Any GI bleeding	1
Abdominal pain	Discomfort or pain in the abdomen	Variable	1

Table 1: Key Symptoms

Understanding the Main Symptoms

Hematemesis

Hematemesis is the vomiting of blood, which may appear bright red or resemble coffee grounds. This symptom strongly suggests an upper GI source, such as the esophagus, stomach, or duodenum. It is the most frequent presenting complaint in upper GI bleeding, occurring in up to 68% of cases in some studies 1 2.

Melena

Melena refers to black, tarry stools produced when blood has been digested as it passes through the GI tract, typically indicating bleeding from the upper GI tract. It is often accompanied by a distinctive, foul odor. Melena may not always be obvious and sometimes requires stool testing to detect 1 2 12.

Hematochezia

Hematochezia is the passage of bright red or maroon blood per rectum. While it most often indicates lower GI bleeding, very brisk upper GI bleeding can also present this way due to rapid transit of blood through the intestines 9 12.

Lightheadedness, Dizziness, and Syncope

Substantial blood loss can lead to symptoms of hypovolemia, such as lightheadedness, dizziness, or even syncope (fainting), especially when standing. These are signs of significant volume loss and possible hemodynamic instability 1 14.

Abdominal Pain

Abdominal pain may accompany GI bleeding, especially if the underlying cause involves inflammation, ulceration, or ischemia 1. However, not all patients with GI bleeding will experience pain.

Types of Gastrointestinal Bleeding

Gastrointestinal bleeding is not a single entity—it can be classified based on its anatomical source, severity, and clinical presentation. Understanding these types helps clinicians target their diagnosis and treatment for optimal outcomes.

Type	Description	Typical Source(s)	Source(s)
Upper GI Bleed	Bleeding from esophagus to duodenum	Esophagus, stomach, duodenum	1 5 6 7 10 15
Lower GI Bleed	Bleeding from small bowel to rectum	Colon, rectum, small intestine	5 9 11 12
Acute	Sudden onset, often severe	Any GI site	7 12 14
Chronic	Slow, ongoing blood loss	Any GI site	9 12

Table 2: Types of GI Bleeding

Classification of GI Bleeding

Upper Gastrointestinal Bleeding (UGIB)

Upper GI bleeding originates from a site proximal to the ligament of Treitz, which includes the esophagus, stomach, and duodenum. UGIB is more common than lower GI bleeding and presents most often with hematemesis or melena 1 5 6 7 10 15. It remains a major cause of hospital admissions and is associated with significant morbidity and mortality.

Lower Gastrointestinal Bleeding (LGIB)

Lower GI bleeding arises from the small intestine (distal to the ligament of Treitz), colon, rectum, or anus. LGIB commonly presents as hematochezia and is often less immediately life-threatening but can still pose significant risks, especially in elderly or comorbid patients 5 9 11 12.

Acute vs. Chronic Bleeding

• Acute GI bleeding is characterized by a sudden onset of overt bleeding (vomiting blood or passing bloody stools) and may be associated with hemodynamic compromise 7 12 14.
• Chronic GI bleeding is more insidious, with slow, ongoing blood loss leading to anemia and subtle symptoms such as fatigue or pallor 9 12.

Causes of Gastrointestinal Bleeding

Identifying the underlying cause of GI bleeding guides treatment and helps prevent recurrence. The causes vary significantly depending on the bleeding’s location.

Location	Common Causes	Less Common Causes	Source(s)
Upper GI	Peptic ulcers, gastritis, esophagitis, varices, Mallory-Weiss tear, cancer	Dieulafoy lesion, GAVE, hemobilia	1 2 6 8 10 15
Lower GI	Diverticulosis, angiodysplasia, neoplasms, hemorrhoids	Meckel's diverticulum, IBD, solitary rectal ulcer	4 9 11 12

Table 3: Causes of GI Bleeding

Causes by Location

Upper GI Causes

Peptic Ulcer Disease: The most common cause, often due to Helicobacter pylori infection or NSAID use 1 6 10 15.

Gastritis and Esophagitis: Inflammation of the stomach or esophagus lining can erode blood vessels and cause bleeding 1 6.

Esophageal or Gastric Varices: Dilated veins, usually from portal hypertension in chronic liver disease, can rupture and bleed massively 2.

Mallory-Weiss Tear: A tear at the gastroesophageal junction, often from forceful vomiting 1 8.

Malignancy: Tumors in the stomach or esophagus can bleed 1 10.

Other Less Common Causes: Dieulafoy lesion, gastric antral vascular ectasia (GAVE), and hemobilia 8.

Lower GI Causes

Diverticulosis: Outpouchings in the colon wall that can erode blood vessels and bleed; most common in the elderly 4 9 11 12.

Angiodysplasia: Fragile, abnormal blood vessels in the colon or small intestine 4 9.

Neoplasms: Polyps or cancers of the colon and rectum 4 9 11.

Hemorrhoids: Swollen veins in the rectum or anus, usually resulting in minor bleeding 4 11.

Other Less Common Causes: Meckel’s diverticulum, inflammatory bowel disease (IBD), solitary rectal ulcer syndrome, colonic varices, radiation injury, and more 4 11.

Risk Factors and Comorbidities

• NSAID use, antiplatelet or anticoagulant therapy, alcohol intake, chronic liver disease, hypertension, and diabetes all increase the risk of GI bleeding 1 2 6.

Treatment of Gastrointestinal Bleeding

The management of GI bleeding is an evolving field, combining rapid assessment, supportive measures, and targeted interventions to control bleeding and prevent complications.

Step	Description	Example/Notes	Source(s)
Stabilization	Fluid resuscitation, blood transfusion	Maintain BP, correct anemia	1 7 14
Risk Stratification	Assessment of severity and urgency	Glasgow-Blatchford, Rockall	1 2 7
Endoscopic Therapy	Direct intervention to stop bleeding	Clips, thermal coagulation, hemostatic sprays	1 13 15
Medications	Acid suppression, eradicate H. pylori	PPIs, antibiotics	1 6 10 15
Radiologic/Surgical	For refractory or inaccessible bleeding	Embolization, surgery	1 7 11

Table 4: Treatment Modalities

Stepwise Approach to Management

Initial Stabilization

The first priority in any GI bleed is stabilizing the patient. This includes:

• Airway protection and oxygen if needed.
• Rapid intravenous fluids (normal saline or lactated Ringer’s) to counteract hypovolemia and maintain blood pressure.
• Blood transfusion if hemoglobin falls below 7 g/dL or if the patient is unstable 1 7 14.
• Monitoring with vital signs and repeated lab assessments.

Risk Stratification

Several scoring systems, such as the Glasgow-Blatchford and Rockall scores, help clinicians predict risk of rebleeding, need for intervention, or likelihood of mortality 1 2 7. These scores inform decisions about timing of investigations and interventions.

Endoscopic Intervention

Urgent endoscopy (within 24 hours) is the gold standard for diagnosing and treating most sources of GI bleeding 1 6 7 14 15.

• Techniques include:
  • Injection therapy (e.g., epinephrine)
  • Thermal coagulation (heater probe, bipolar forceps)
  • Mechanical methods (clips, band ligation)
  • Novel methods like hemostatic powder sprays (Hemospray), which have shown promising results in controlling bleeding when conventional methods fail 13.

Endoscopic hemostasis is typically first-line for upper GI bleeding, as well as for many lower GI sources 1 15.

Medication Management

• Proton Pump Inhibitors (PPIs): Initiated upon presentation for upper GI bleeding to stabilize clots and reduce risk of rebleeding 1 6 10 15.
• Eradication of H. pylori: For patients with peptic ulcer bleeding due to infection 10.
• Withholding or balancing anticoagulant/antiplatelet drugs: Particularly in patients at risk for cardiovascular events; resuming therapy is a complex, individualized decision 7.

Radiological and Surgical Interventions

When endoscopic therapy fails or the source of bleeding is inaccessible, radiologic embolization or surgery may be necessary 1 7 11. Surgery is reserved for refractory cases.

Special Considerations in Lower GI Bleeding

• Colonoscopy is the main diagnostic and therapeutic tool for most cases of lower GI bleeding 11 12.
• Angiography or CT angiography may help localize bleeding in massive or ongoing cases 11.

Conclusion

Gastrointestinal bleeding is a complex clinical problem requiring an integrated, evidence-based approach. Early recognition of symptoms, careful classification by type and location, identification of underlying causes, and timely, targeted treatment are critical to improving patient outcomes.

Key Takeaways:

• GI bleeding can present with hematemesis, melena, or hematochezia; associated symptoms include lightheadedness and syncope 1 2 9 12.
• Classification into upper and lower GI bleeding guides diagnosis and management 1 5 9 11.
• Common causes vary by location, with peptic ulcers and varices for upper GI, and diverticulosis and angiodysplasia for lower GI 1 6 9 11.
• Management includes initial stabilization, risk stratification, endoscopic therapy, medications (PPIs, antibiotics), and, if needed, radiologic or surgical intervention 1 6 7 13 15.
• Early endoscopic intervention and multidisciplinary care are vital for reducing morbidity and mortality 2 7 14 15.

Patients experiencing symptoms suggestive of GI bleeding should seek immediate medical attention. With prompt and systematic care, most cases can be effectively managed, and outcomes continue to improve with advances in therapy and technology.