Differential Diagnosis for a 13-year-old Girl with Right Lower Abdominal Pain
Single Most Likely Diagnosis
- Mittelschmerz: This condition, also known as ovulatory pain, occurs in some individuals during ovulation, which can happen around the time of menstruation. The pain is typically mid-cycle but can vary, and it's often localized to one side of the lower abdomen. The absence of tenderness, fever, and other alarming signs supports this diagnosis.
Other Likely Diagnoses
- Dysmenorrhea: Although the pain is usually more central and crampy, some individuals may experience localized pain. The timing with the menstrual cycle and the lack of other symptoms make this a plausible option.
- Ovarian Cyst: Simple ovarian cysts can cause intermittent, often sharp pain, especially if they rupture or torsion occurs. However, the absence of significant tenderness and systemic symptoms makes this less likely but still a consideration.
Do Not Miss Diagnoses
- Appendicitis: Although the classic presentation of appendicitis includes tenderness, fever, and elevated white blood cell count, atypical presentations can occur, especially in young females. Appendicitis can be deadly if missed, particularly if it ruptures, so it must be considered even with a low probability.
- Ectopic Pregnancy: Though less likely in a 13-year-old, it's crucial to consider in any female of childbearing age presenting with lower abdominal pain. A pregnancy test should be performed to rule out this life-threatening condition.
- Ovarian Torsion: This is a surgical emergency that can present with sudden, severe pain, often without significant findings on exam initially. It's essential to maintain a high index of suspicion for ovarian torsion in any female with acute abdominal pain.
Rare Diagnoses
- Endometriosis: While endometriosis can cause cyclic pain, it's less common in young teenagers and usually presents with a longer history of symptoms.
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease or ulcerative colitis can cause chronic abdominal pain but typically include other symptoms like changes in bowel habits, weight loss, and systemic symptoms.