Differential Diagnosis for Right Quadrant Pain
The differential diagnosis for right quadrant pain can be organized into the following categories:
- Single Most Likely Diagnosis
- Appendicitis: This is the most common cause of right lower quadrant pain, especially if it is accompanied by fever, nausea, vomiting, and rebound tenderness. The pain often starts near the navel and then moves to the right lower quadrant.
- Other Likely Diagnoses
- Cholecystitis: Inflammation of the gallbladder, usually due to gallstones, can cause right upper quadrant pain, fever, and leukocytosis.
- Pyelonephritis: A bacterial infection of the kidney can cause flank pain, which may radiate to the right quadrant, accompanied by fever, dysuria, and frequency.
- Hepatitis: Inflammation of the liver can cause right upper quadrant pain, jaundice, and elevated liver enzymes.
- Intestinal obstruction: A blockage in the intestine can cause severe abdominal pain, nausea, vomiting, and constipation.
- Do Not Miss Diagnoses
- Ruptured ectopic pregnancy: Although less common, a ruptured ectopic pregnancy can cause severe right lower quadrant pain, especially in women of childbearing age, and is a medical emergency.
- Ruptured abdominal aortic aneurysm: A tear in the aorta can cause severe abdominal pain, which may radiate to the back, and is often accompanied by hypotension and shock.
- Perforated viscus: A hole in the wall of the intestine can cause severe abdominal pain, fever, and peritonitis.
- Ovarian torsion: Twisting of the ovary can cause severe right lower quadrant pain, nausea, and vomiting, especially in women.
- Rare Diagnoses
- Carcinoid tumor: A rare tumor of the small intestine can cause abdominal pain, flushing, and diarrhea.
- Mesenteric ischemia: A decrease in blood flow to the intestine can cause severe abdominal pain, which may be out of proportion to the physical examination findings.
- Right-sided diverticulitis: Inflammation of a diverticulum in the right colon can cause right lower quadrant pain, fever, and changes in bowel habits.
- Porphyria: A group of rare genetic disorders can cause abdominal pain, neurological symptoms, and psychiatric disturbances.