Complex regional pain syndrome

Disease Description (Causes and Symptoms)

• Definition summary: Abdominal pain is pain arising from abnormalities in various organs inside or outside the abdominal cavity. Because its causes and pathophysiology are highly diverse, it is important to identify the cause through an accurate medical history, physical examination, and necessary tests.
• Main causes (categories): Gastrointestinal diseases (gastritis, ulcers, colitis, intestinal obstruction, appendicitis, etc.), liver and biliary tract diseases (hepatitis, liver cancer, cholecystitis, gallstones, common bile duct stones), pancreatic diseases (acute or chronic pancreatitis, pancreatic cancer), vascular diseases (abdominal/thoracic aortic aneurysm, aortic dissection), genitourinary diseases (pyelonephritis, urinary stones, ectopic pregnancy, ovarian diseases, etc.), tumors (stomach, colon, liver, pancreas, ovary, etc.), and infectious or inflammatory diseases (enteritis, appendicitis, sepsis), among others.
• Pathophysiology summary: Visceral pain originating from organs, somatic pain caused by involvement of the body wall or peritoneum, and referred or radiating pain felt in another area due to reflected stimulation from an organ may occur together. When peritonitis develops, localized and severe peritoneal irritation signs appear.
• Symptom characteristics (examples by location, for reference):
  • Right upper abdomen: Gallstones or cholecystitis (pain may radiate to the shoulder), liver disease (dull pain)
  • Left upper abdomen: Gastritis, gastric ulcer, duodenal and pancreatic diseases
  • Right lower abdomen: Appendicitis, colon disease, female reproductive system diseases (related to the ovaries or uterus)
  • Pain throughout the abdomen: Acute peritonitis, intestinal obstruction, extensive inflammatory bowel disease
• Important accompanying symptoms: Fever, vomiting, diarrhea or constipation, bloody stool, jaundice, urinary abnormalities, vaginal bleeding or changes in the menstrual cycle, and signs of shock (low blood pressure or impaired consciousness) are important for determining the cause and the urgency

Treatment Methods

• Principle of prioritizing diagnosis: First determine whether emergency surgery is needed (for intestinal perforation, peritonitis, intestinal obstruction, ruptured abdominal aortic aneurysm, etc.). Promptly perform a medical history and physical examination, blood tests (inflammatory, liver, and pancreatic markers), urinalysis, and clinical imaging (abdominal ultrasound and CT). Women need a pregnancy test.
• Conservative treatment: Fluid replacement (to correct dehydration or shock), fasting (NPO), and insertion of a tube for gastrointestinal drainage when necessary; use of analgesics and antiemetics (select analgesics according to the cause; use caution with NSAIDs and opioids because they may risk delaying diagnosis); antibiotics (when bacterial peritonitis or infection is suspected); and electrolyte correction.
• Drug treatment (by cause): Gastrointestinal or inflammatory lesions (proton pump inhibitors and antibiotics when necessary), biliary tract diseases (antibiotics for biliary tract infections), pancreatitis (fluid replacement, analgesia, and nutritional management), and urinary stones (analgesia, hydration, lithotripsy, or surgery).
• Procedural and surgical treatment: Appendectomy, cholecystectomy (laparoscopy preferred), ERCP (removal of common bile duct stones and treatment of biliary tract disease), surgery for intestinal adhesions or obstruction, emergency surgery for intestinal perforation, bleeding, or cancer, and vascular surgical repair of abdominal aortic aneurysm or dissection.
• Lifestyle management and rehabilitation: Cause-specific dietary adjustments (such as a low-fat diet and adjustment of fiber intake), abstinence from alcohol (for pancreatic or liver disease), regular bowel movements and adequate fluid intake, and consultation about whether to discontinue medications (for example, reducing NSAID use).
• Precautions and risk of complications: Take care not to delay diagnosis by merely suppressing pain with analgesics. If emergency signs occur (severe pain, fever, a sharp rise in pancreatic or liver enzymes, peritoneal irritation signs, or hemodynamic instability), go to the emergency room immediately. Possible complications include intestinal perforation, peritonitis, sepsis, intestinal ischemia, bleeding, intestinal obstruction, and renal failure.

Checklist Before an Outpatient Visit (Including What to Bring, Records, and Sample Questions)

• Recommended items to bring:
  • A list of all medications currently being taken (including prescription drugs, over-the-counter drugs, and supplements) and the times they are taken
  • A history of previous surgeries and hospitalizations, and major medical or surgical records (if available)
  • Copies of recent test results (blood tests, urinalysis, ultrasound, CT, etc.), or the dates and names of the hospitals where they were performed
  • A pain diary (onset time, location, intensity, character [stabbing, dull, cramping, etc.], aggravating and relieving factors, and accompanying symptoms)
  • For women, the date of the last menstrual period and information about contraception or the possibility of pregnancy
• Self-check items before an outpatient visit: Whether there is a fever, the number and characteristics of vomiting episodes, changes in bowel movements or gas passage (none or reduced), urinary changes (frequent urination or blood in the urine), whether symptoms worsen after eating, and any history of the same symptoms and response to treatment
• Information to tell the doctor first during the outpatient visit (prepare answers to sample questions): When the pain began and whether its location has shifted, any recent trauma, travel, or history of emergency surgery, and whether anticoagulants are being taken

General Sample Questions to Ask the Doctor

• "Which of the possible causes of my symptoms is most suspected?"
• "What tests do I need now (blood tests, imaging, urine tests, etc.), and is this an emergency?"
• "What are the main side effects of the medication you plan to prescribe, and what precautions should I take when taking it?"
• "What symptoms should be considered an emergency? When should I go to the emergency room?"
• "What is the prognosis, and what lifestyle changes can I make to reduce the risk of recurrence?"

Examples of Disease-Specific Questions

• If pancreatic or biliary disease is suspected: "Do the symptoms worsen after eating, especially fatty foods? Have you ever been diagnosed with gallstones or pancreatitis?"
• For right lower abdominal pain (when appendicitis or a gynecological disease is suspected): "Did the pain start around the navel and then move to the lower right abdomen? What is the status of your menstrual cycle, and is pregnancy possible?"

(Note: Diagnosis and treatment vary depending on the medical history, physical examination, and test results. If emergency findings are suspected, you are advised to visit the emergency room without delay.)