Differential Diagnosis for Left Lower Abdominal Pain in a 39-Year-Old Male
Single Most Likely Diagnosis
- Diverticulitis: This condition is a common cause of left lower abdominal pain in adults, especially in the 30-50 year age range. The pain is typically constant, severe, and may be accompanied by changes in bowel habits, fever, and nausea.
Other Likely Diagnoses
- Irritable Bowel Syndrome (IBS): IBS can cause chronic or recurrent abdominal pain, often localized to the left lower quadrant, accompanied by changes in bowel habits such as constipation or diarrhea.
- Constipation: Severe constipation can cause significant abdominal pain, often in the left lower quadrant, due to the accumulation of feces in the sigmoid colon.
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease or ulcerative colitis can cause chronic abdominal pain, diarrhea, weight loss, and other symptoms, with pain often localized to the left lower quadrant.
Do Not Miss Diagnoses
- Ectopic Pregnancy (in a female patient, but included for completeness): Although the patient is male, it's essential to remember this condition in female patients, as it is life-threatening and can present with abdominal pain.
- Appendicitis (if pain has shifted): While appendicitis typically presents with right lower quadrant pain, it can occasionally present with left lower quadrant pain if the appendix is retrocecal or if the pain has shifted.
- Intestinal Obstruction: This is a surgical emergency that can cause severe abdominal pain, vomiting, and constipation. It may not always present with typical symptoms, making it crucial not to miss.
- Mesenteric Ischemia: This condition involves insufficient blood flow to the intestines and can cause severe, sudden-onset abdominal pain, often out of proportion to physical examination findings.
Rare Diagnoses
- Ovarian Torsion (in a female patient): Similar to ectopic pregnancy, this is included for completeness and is relevant only in female patients. It's a gynecological emergency that can cause severe, sudden-onset abdominal pain.
- Lead Poisoning: Can cause severe abdominal pain, often accompanied by constipation, and is a rare but important consideration in patients with exposure history.
- Henoch-Schönlein Purpura (HSP): A form of vasculitis that can cause abdominal pain, gastrointestinal bleeding, and a characteristic rash. It's more common in children but can occur in adults.
- Intra-abdominal Testicular Torsion: An extremely rare condition where an intra-abdominal testicle undergoes torsion, causing severe abdominal pain.