Pathophysiology
P-II-2. Gastrointestinal disease, Case 2
消化管疾患 症例2
A 68-year-old male patient presents to the emergency department with weakness and dizziness. He says that his stools have changed color for 2 days and he has been passing large amounts of very dark colored stools. There was no vomiting, fresh red bloody stools, or bloody urine. History of smoking, IHD, hypertension, hypercholesterolemia. His medications are atorvastatin 10mg 1 tbl in the evening, acetylsalicylic acid 100mg 1 tbl/day, ramipril 10mg 1 tbl/day and hydrochlorothiazide 25mg 1 tbl/day.
On examination: pale male patient, RR: 115/70 mmHg, HR: 102/min, symmetric thorax, normal breathing sounds and bilateral chest excursion, heart rhythmic, clear cardiac sounds, no murmur can be heard, abdomen soft, palpable, minimal epigastric tenderness, no abnormal resistance, no défense, normal bowel sounds. On RDE (rectal digitalis examination) melena is found. Peripheral blood vessels are well palpable, with no audible vascular murmurs.
Laboratory findings: Hgb: 110 gr/l, Htk: 32%, RBC: 3.9 T/l, MCV: 84 fl, PTL: 360 G/l, WBC: 9.8 G/l, glucose (fasting): 6.2 mmol/l, BUN: 6.0 mmol/l, creatinine: 126 μmol/l, ALAT: 40 U/l, ASAT: 60 U/l, ALP: 112 U/l, GGT: 45 U/l, cholesterol: 6.0 mmol/l, HDL cholesterol: 0.7 mmol/l, triglycerides: 1.6 mmol/l, sodium: 145 mmol/l, potassium: 4.0 mmol/l. No abnormalities in urine.
Gastro-duodenoscopy: minimal fresh blood in the stomach, edematous mucosa of the bulbus duodeni, superficial ulceration of about 1 cm in diameter on the anterior wall of it, with blood oozing from it. Biopsy and hemostasis is performed (clip application, Tonogen injection).
Key Quotes & What They Tell Us
| Quote / Value | Interpretation |
|---|---|
| “passing large amounts of very dark colored stools” + RDE: “melena” | Melena → digested blood from an upper GI source (proximal to the colon) |
| “weakness and dizziness”, pale, HR 102/min, RR 115/70 mmHg | Symptoms and signs of acute blood loss / early haemodynamic compromise |
| “acetylsalicylic acid 100 mg 1 tbl/day” | Aspirin impairs mucosal protection → major risk factor for peptic ulceration and bleeding |
| Hgb 110 g/L, Htk 32% (anaemia); MCV 84 (normocytic) | Acute/subacute blood loss anaemia |
| Endoscopy: “superficial ulceration … anterior wall of [duodenal bulb], with blood oozing” | Active bleeding duodenal (peptic) ulcer — the source confirmed and treated |
| “No vomiting, fresh red bloody stools” | Argues against a brisk upper bleed (no haematemesis) or a lower GI source (no fresh blood) |
Key Points
- Diagnosis: Upper gastrointestinal bleeding from a bleeding duodenal (peptic) ulcer.
- Key sign: Melena localizes the bleed to an upper source; confirmed at gastroduodenoscopy.
- Risk factor: Daily aspirin (antiplatelet + mucosal injury) on a background of cardiovascular disease.
- Pathophysiology: Mucosal defence breakdown → acid-peptic ulceration → erosion into a vessel → haemorrhage.
- Management shown: Endoscopic haemostasis (clip + adrenaline/Tonogen injection) and biopsy.
一問一答
▶What is the diagnosis in an elderly aspirin user with melena, anaemia, and a bleeding duodenal ulcer on endoscopy?
Upper gastrointestinal bleeding from a bleeding duodenal (peptic) ulcer.
▶What is melena and what does it indicate about the bleeding site?
Black, tarry stool from digested blood, indicating an upper GI source (proximal to the colon).
▶How does daily aspirin promote peptic ulcer bleeding?
It inhibits prostaglandin-mediated mucosal protection and impairs platelet function, predisposing to ulceration and bleeding.
▶Why does this patient have weakness, dizziness, pallor, and tachycardia?
Acute blood loss reduces circulating volume and oxygen-carrying capacity, causing these symptoms/signs.
▶What is the pathophysiology of peptic ulcer formation?
An imbalance between aggressive factors (acid, pepsin, H. pylori, NSAIDs) and mucosal defences leads to mucosal erosion/ulceration.
▶What is the other major cause of peptic ulcers besides NSAIDs?
Helicobacter pylori infection.
▶Why is the absence of haematemesis and fresh rectal blood informative?
It argues against a brisk upper bleed and against a lower GI source, fitting a slow upper GI bleed producing melena.
▶What endoscopic treatments were used to stop the bleeding ulcer?
Clip application and adrenaline (Tonogen) injection for haemostasis.
▶Why does Hgb 110 g/L with normocytic indices fit acute blood loss?
Acute haemorrhage lowers haemoglobin while cells remain normal in size (normocytic) before any chronic changes.
▶Why is a raised BUN (relative to creatinine) common in upper GI bleeding?
Digestion and absorption of blood protein in the gut raises urea, often with relatively normal creatinine.
▶What drug class is used to promote healing and reduce rebleeding of peptic ulcers?
Proton pump inhibitors (acid suppression).
▶How do proton pump inhibitors help in bleeding peptic ulcers?
Raising gastric pH stabilizes clots and promotes mucosal healing, reducing rebleeding risk.
▶What serious complication can occur if a peptic ulcer erodes through the wall?
Perforation, causing peritonitis (a surgical emergency).
▶Why is biopsy performed during endoscopy of an ulcer?
To check for H. pylori and to exclude malignancy.
▶What initial resuscitation is needed in significant upper GI bleeding?
IV access and fluid/blood resuscitation to restore circulating volume.
▶Why does epigastric tenderness occur in duodenal ulcer disease?
Acid-peptic inflammation/ulceration of the duodenal/gastric mucosa causes localized epigastric pain and tenderness.
▶Why are elderly patients on cardiovascular medications at particular risk of GI bleeding?
Antiplatelet/anticoagulant drugs (e.g. aspirin) increase bleeding risk, and comorbidities reduce reserve.
▶How does upper GI bleeding differ from lower GI bleeding in stool appearance?
Upper bleeds typically cause black, tarry melena; lower bleeds cause fresh red blood (haematochezia).
▶What is the first-line investigation in suspected upper GI bleeding?
Upper gastrointestinal endoscopy (gastroduodenoscopy), which is both diagnostic and therapeutic.
▶Why should aspirin use be reviewed after a bleeding peptic ulcer?
Its benefit must be balanced against bleeding risk; it may be paused and gastroprotection (PPI) added when continued.