Differential Diagnosis for 30-year-old Female with Right Lower Quadrant Abdominal Pain
- Single Most Likely Diagnosis
- Pelvic Inflammatory Disease (PID): The combination of right lower quadrant abdominal pain, prominent pelvic lymph nodes, possible pelvic congestion, and a dirty urinalysis (U/A) suggests an infectious process. PID is a common cause of lower abdominal pain in women, especially with the presence of a dirty U/A indicating a possible urinary tract infection or cervicitis, which can be associated with PID.
- Other Likely Diagnoses
- Ovarian Cyst-Related Pain: The incidental finding of a left ovarian cyst and a dominant left ovarian follicle could be contributing to her pain, especially if there is any associated ovarian cyst rupture or hemorrhage, even though torsion is ruled out.
- Urinary Tract Infection (UTI): The dirty U/A suggests a UTI, which could cause lower abdominal pain. The presence of UTI does not exclude other diagnoses but could be a contributing factor.
- Do Not Miss Diagnoses
- Ectopic Pregnancy: Although not directly suggested by the findings, any female of childbearing age with abdominal pain should be considered for ectopic pregnancy, especially if there's any chance of pregnancy. It's a life-threatening condition that requires immediate attention.
- Ovarian Torsion: Despite the ultrasound showing no evidence of torsion, this is a critical diagnosis not to miss due to its emergency nature. Clinical suspicion should remain high if the pain pattern changes or worsens.
- Appendicitis with Atypical Presentation: Although the CT shows a normal appendix, atypical presentations can occur, especially in females where the appendix can be retrocecal or in other unusual locations, potentially not visualized properly on CT.
- Rare Diagnoses
- Endometriosis: Could be a cause of chronic pelvic pain and might be considered if other diagnoses are ruled out, especially with the presence of ovarian cysts and pelvic congestion.
- Diverticulitis: Less common in this age group but could present with right lower quadrant pain if the diverticula are in the sigmoid colon, which can sometimes present more laterally or even on the right side in rare cases.