Differential Diagnosis for Lower Quadrant Abdominal Mass
Single Most Likely Diagnosis
- Diverticulitis: This condition is a common cause of lower quadrant abdominal pain and mass, especially in older adults. The presence of a palpable mass in the lower abdomen, combined with symptoms like pain, fever, and changes in bowel habits, makes diverticulitis a leading consideration.
Other Likely Diagnoses
- Appendicitis: Although appendicitis typically presents with pain that migrates to the right lower quadrant, it can sometimes present atypically, especially if the appendix is retrocecal. A mass might be palpable if an appendiceal abscess has formed.
- Ovarian Cyst or Tumor: In females, ovarian pathology is a common cause of lower quadrant abdominal masses. These can range from benign cysts to malignant tumors, and the presentation can vary widely.
- Intestinal Obstruction: While not always causing a distinct mass, intestinal obstruction can lead to distension and potentially a palpable mass in the lower abdomen, depending on the location and cause of the obstruction.
Do Not Miss Diagnoses
- Ectopic Pregnancy: In women of childbearing age, an ectopic pregnancy can present with abdominal pain and a mass, although the mass might not always be palpable. This condition is life-threatening and requires immediate diagnosis and treatment.
- Ruptured Abdominal Aortic Aneurysm: Although this typically presents with a midline or back mass, a ruptured abdominal aortic aneurysm can occasionally cause a lower quadrant mass due to retroperitoneal hemorrhage. It is a medical emergency.
- Incarcerated or Strangulated Hernia: Hernias in the lower abdomen can become incarcerated or strangulated, leading to severe pain, a palpable mass, and potentially life-threatening complications if not promptly treated.
Rare Diagnoses
- Lymphoma: Abdominal lymphoma can cause masses in various locations, including the lower quadrants, although this is less common.
- Retroperitoneal Sarcoma: These are rare tumors that arise in the retroperitoneal space and can present as a lower quadrant abdominal mass.
- Psoas Abscess: An abscess in the psoas muscle can cause a lower quadrant mass and is often associated with back pain and fever. It is more common in patients with underlying conditions like spinal infection or Crohn's disease.