Differential Diagnosis for Abdominal Pain in a Post-Hysterectomy Patient with Elevated CRP and Normal CT Scan

Given the patient's symptoms of abdominal pain primarily in the right lower quadrant, a history of hysterectomy, a normal CT scan of the abdominal pelvis, and an elevated CRP, the following differential diagnoses are considered:

• Single Most Likely Diagnosis
  • Musculoskeletal Pain: Given the normal CT scan and the history of hysterectomy, musculoskeletal pain is a plausible cause. The elevated CRP could be indicative of inflammation, which might not be visible on a CT scan, especially if it's related to muscle or soft tissue injury.
• Other Likely Diagnoses
  • Diverticulitis: Although the CT scan is normal, early or mild diverticulitis might not always be visible. The elevated CRP supports an inflammatory process, and diverticulitis can cause right lower quadrant pain if the affected diverticula are in the right colon.
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease or ulcerative colitis can cause abdominal pain and elevated CRP. The normal CT scan does not entirely rule out IBD, as early disease or certain types of IBD might not be evident on imaging.
  • Gastroenteritis: An infection of the stomach and intestines can cause abdominal pain and inflammation, leading to an elevated CRP. The symptoms could be localized to the right lower quadrant, depending on the area of the intestine affected.
• Do Not Miss Diagnoses
  • Appendicitis: Although the patient has had a hysterectomy and the CT scan is normal, appendicitis is a critical diagnosis that must not be missed. Atypical presentations can occur, especially in older adults or those with a history of abdominal surgery, which can alter anatomical landmarks.
  • Ovarian Remnant Syndrome: If ovarian tissue was inadvertently left behind during the hysterectomy, it could cause cyclic pain or inflammation, leading to elevated CRP. This condition is rare but important to consider in post-hysterectomy patients with abdominal pain.
• Rare Diagnoses
  • Epididymitis or Orchitis (in males, but considering rare anatomical variations): Extremely rare in females, but in cases of unusual anatomy or androgen insensitivity syndrome, these conditions could theoretically cause right lower quadrant pain.
  • Abdominal Wall Endometriosis: Although the patient has undergone a hysterectomy, if endometrial tissue was implanted in the abdominal wall during the surgery, it could cause cyclical pain and inflammation, potentially leading to an elevated CRP.

Each of these diagnoses requires careful consideration of the patient's history, physical examination findings, and potentially additional diagnostic tests to determine the cause of the abdominal pain and elevated CRP.