Differential Diagnosis for Sharp RLQ Abdominal Pain
- Single Most Likely Diagnosis
- Appendicitis: This is the most common cause of sharp right lower quadrant (RLQ) abdominal pain, especially if the pain is severe, constant, and accompanied by fever, nausea, vomiting, and loss of appetite. The pain often starts around the navel and then moves to the RLQ.
- Other Likely Diagnoses
- Ovarian cyst or torsion: In females, a ruptured ovarian cyst or ovarian torsion can cause severe, sharp pain in the RLQ. These conditions are often accompanied by nausea, vomiting, and sometimes fever.
- Kidney stone: A stone in the right ureter can cause severe, sharp pain in the RLQ, radiating to the groin. The pain is often colicky (comes and goes) and can be accompanied by nausea, vomiting, and blood in the urine.
- Diverticulitis: Inflammation of a diverticulum in the right colon can cause sharp pain in the RLQ, fever, nausea, and changes in bowel habits.
- Do Not Miss Diagnoses
- Ectopic pregnancy: Although less common, an ectopic pregnancy can present with sharp RLQ pain, especially in females of childbearing age. It's a life-threatening condition if not promptly diagnosed and treated.
- Ruptured abdominal aortic aneurysm: While less common in the RLQ, a ruptured abdominal aortic aneurysm can cause severe abdominal pain that may radiate to the back and is a medical emergency.
- Intussusception: A condition where a part of the intestine slides into an adjacent part, which can cause severe abdominal pain, vomiting, and bloody stools. It's more common in children but can occur in adults.
- Rare Diagnoses
- Mesenteric lymphadenitis: Inflammation of the lymph nodes in the mesentery can mimic appendicitis, causing sharp RLQ pain, fever, and nausea.
- Right-sided inguinal hernia: A hernia can cause sharp pain in the RLQ, especially if it becomes incarcerated or strangulated.
- Meckel's diverticulitis: Inflammation of a Meckel's diverticulum, a congenital anomaly of the small intestine, can cause sharp RLQ pain, fever, and nausea.