Lower Abdominal Pain Diagnostic Differential
The differential diagnosis for lower abdominal pain 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 for lower abdominal pain, especially if the pain is localized to the right lower quadrant. The justification for this being the most likely diagnosis lies in its relatively high frequency and the severity of complications if not promptly treated.
- Other Likely Diagnoses
- Ovarian cysts or torsion: These conditions are common in women and can cause severe lower abdominal pain. The pain can be sudden and may be accompanied by nausea and vomiting.
- Urinary tract infections (UTIs) or kidney stones: These conditions can cause lower abdominal pain, often accompanied by dysuria, frequency, or hematuria.
- Diverticulitis: Inflammation of the diverticula in the colon can cause lower abdominal pain, usually on the left side, and may be accompanied by changes in bowel habits or fever.
- Inflammatory bowel disease (IBD): Conditions like Crohn's disease or ulcerative colitis can cause chronic lower abdominal pain, diarrhea, weight loss, and sometimes blood in the stool.
- Do Not Miss Diagnoses
- Ectopic pregnancy: Although less common, an ectopic pregnancy is a life-threatening condition that must be considered, especially in women of childbearing age presenting with lower abdominal pain and a positive pregnancy test.
- Ruptured abdominal aortic aneurysm: This is a medical emergency that can present with severe lower abdominal or back pain and is more common in older adults with risk factors for vascular disease.
- Intestinal obstruction: This can cause severe abdominal pain, vomiting, and constipation, and requires prompt surgical intervention to prevent complications.
- Rare Diagnoses
- Endometriosis: While not rare in the general population, it is less likely to be the primary cause of acute lower abdominal pain but can cause chronic pain.
- Pudendal neuralgia: A rare condition causing chronic pain in the distribution of the pudendal nerve.
- Lower abdominal lymphoma: Although rare, lymphoma can cause abdominal pain, and a diagnosis would significantly impact treatment and prognosis.
Each of these diagnoses has distinct characteristics and risk factors that can help guide the diagnostic process. A thorough history, physical examination, and appropriate diagnostic tests are essential for making an accurate diagnosis.