Case History:

A 16 yo female comes with complaint of left lower back pain for the past 4 days. The pain is worst when she urinates. She was diagnosed with Crohn’s Disease 2 years ago and is being treated by a gastroenterologist. She is not currently having an exacerbation of Crohn’s, and reports that she has never felt this pain before. She is not sexually active and at the time of the visit was having her menstrual period. On physical examination, the patient had LLQ tenderness, with no rebound or guarding. The left lower back pain was not reproducible on palpation.

Differential Diagnosis:

The differential diagnosis of LLQ tenderness in this patient is complicated due to her Crohn’s disease. It is possible that the back pain and LLQ tenderness is an atypical Crohn’s exacerbation for her. Patients with Crohn’s disease are also at risk for ureteral stones and fistulas. The fact that the pain is worse with urination suggests the presence of a stone. It is also possible that her back pain is due to menstrual cramping. In a typical female, the differential diagnosis of LLQ tenderness includes ectopic pregnancy, PID, and ovarian cyst. Since the patient is a virgin, ectopic pregnancy and PID is unlikely. The diagnosis of a cyst is supported by the onset of pain during menstruation. The patient was sent for an abdominal ultrasound that revealed a 3cm by 3cm cyst on her left ovary.

What does the literature say?:

Another study demonstrated that ovarian cysts can be confused with other conditions in adolescents, especially appendicitis. In this study (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15094575) 297 adolescent females that had either appendicitis or ovarian cysts were studied retrospectively. Of these females, 38% were given a preliminary diagnosis of appendicitis in the ER, 3 of whom were eventually discovered to have an ovarian cyst at surgery.

Why is this information important and what did I learn?:

This information is important because it might save a patient unnecessary and possibly invasive diagnostic procedures. When patients present with abdominal pain gastrointestinal causes are frequently thought of first. However, what the above studies suggest is that in adolescent females, one must also consider ovarian lesions. In this case a mis- or non-diagnosis would be costly, since complications of ovarian lesions range from infertility to death.