Differential Diagnosis for Peritoneal Inflammation

The differential diagnosis for peritoneal inflammation is broad and can be categorized based on the likelihood and potential impact of missing a diagnosis.

• Single Most Likely Diagnosis
  • Appendicitis: This is often the first consideration in cases of acute peritoneal inflammation, especially if the pain is localized to the right lower quadrant. The justification for this being the most likely diagnosis stems from its common occurrence and the severity of complications if not promptly treated.
• Other Likely Diagnoses
  • Diverticulitis: Inflammation of a diverticulum in the digestive tract, commonly the colon, can cause peritoneal irritation, especially if the diverticulum ruptures.
  • Perforated Peptic Ulcer: A hole in the stomach or duodenum can leak digestive enzymes into the peritoneal cavity, causing severe inflammation.
  • Ovarian Torsion or Rupture: In females, these conditions can lead to sudden, severe abdominal pain and peritoneal irritation.
  • Intestinal Obstruction: Blockage of the intestine can lead to ischemia and subsequent perforation, causing peritoneal inflammation.
• Do Not Miss Diagnoses
  • Ectopic Pregnancy: Although less common, this condition is critical to identify early due to its high mortality rate if not promptly treated.
  • Ruptured Aortic Aneurysm: While not directly causing peritoneal inflammation, the rupture can lead to retroperitoneal hemorrhage, which may irritate the peritoneum and is a medical emergency.
  • Mesenteric Ischemia: Reduced blood flow to the intestines can lead to ischemia and necrosis, causing peritoneal inflammation and is often underdiagnosed.
• Rare Diagnoses
  • Primary Peritoneal Carcinoma: A rare cancer that arises from the peritoneum itself, which can cause chronic inflammation.
  • Tuberculous Peritonitis: In areas where tuberculosis is common, this can be a rare cause of peritoneal inflammation.
  • Familial Mediterranean Fever: A genetic disorder that can cause recurrent episodes of peritoneal inflammation among other symptoms.
  • Sclerosing Encapsulating Peritonitis: A rare condition characterized by a thick, fibrotic membrane encasing the intestines, leading to bowel obstruction and peritoneal inflammation.

Each of these diagnoses has distinct clinical presentations, and a thorough history, physical examination, and diagnostic workup are essential for accurate diagnosis and management.