Differential Diagnosis for Left Lower Quadrant Pain

The patient presents with left lower quadrant pain that worsens with walking, to the point of significant discomfort and altered gait. This symptomatology can be associated with various conditions, each with different levels of urgency and potential impact on the patient's health.

• Single Most Likely Diagnosis

  • Diverticulitis: This condition is characterized by inflammation of the diverticula in the colon, often presenting with left lower quadrant pain, fever, and changes in bowel habits. The pain's location and the fact that it worsens with movement (such as walking) make diverticulitis a plausible diagnosis, especially in a 39-year-old female, as the incidence of diverticulitis increases with age.

• Other Likely Diagnoses

  • Ovarian Cyst or Torsion: Given the patient's gender, ovarian pathology must be considered. An ovarian cyst can cause significant pain, especially if it ruptures or torsion occurs. The pain is typically sharp and can be exacerbated by movement.
  • Kidney Stone: A stone in the left ureter can cause severe, colicky pain that radiates to the groin and is worsened by movement. The pain can be so severe that it leads to a hunched-over posture.
  • Constipation: Severe constipation can cause significant abdominal pain, particularly if there is a large fecal impaction. The pain can be localized to the left lower quadrant if the impaction is in the sigmoid colon.

• Do Not Miss Diagnoses

  • Ectopic Pregnancy: Although less likely given the duration of symptoms, an ectopic pregnancy must be ruled out in any female of childbearing age presenting with abdominal pain. This condition is life-threatening and requires immediate intervention.
  • Appendicitis: While appendicitis typically presents with right lower quadrant pain, it can occasionally present atypically, especially if the appendix is retrocecal. Missing appendicitis can lead to perforation and severe consequences.
  • Intestinal Obstruction: An obstruction in the intestines can cause severe abdominal pain, vomiting, and constipation. It is a surgical emergency and must be identified promptly to prevent complications.

• Rare Diagnoses

  • Inflammatory Bowel Disease (IBD) Flare: Conditions like Crohn's disease or ulcerative colitis can cause left lower quadrant pain, especially if the disease is localized to the sigmoid colon. However, these conditions typically have a more chronic course with diarrhea, weight loss, and other systemic symptoms.
  • Endometriosis: Endometriosis can cause chronic pelvic pain, but it is less likely to cause acute, severe pain that worsens with walking unless there is a specific event like a ruptured endometrioma.
  • Neurological Causes: Rarely, abdominal pain can be referred from neurological sources, such as nerve root compression or neuropathies. These would be considered after other more common causes have been ruled out.