Laboratory and radiological tests can be obtained to collect additional information about the pelvic pain. Physicians ideally choose from the large battery of available potential tests based on the initial history and physical examination as well as the ability of the test result to make a change in the patient's management plan.
Infectious causes for pain are more common in some populations than others but even women at low risk occasionally develop these infections, the infections are usually treatable if identified, and the tests are relatively inexpensive. Therefore, it is usually considered prudent to collect pelvic, urinary and/or blood samples for common infections.
Urine testing can be performed when there is a suspicion of involvement of the genitourinary system. A simple urinalysis can rule out hematuria (blood in the urine, even microscopic amounts), which if present can suggest kidney stones, an infection in the bladder or even (rarely) bladder carcinoma.
Stool testing is advisable if there is coexisting diarrhea with pelvic pain. A stool sample for ova and parasites can assess infections involving Giardia or parasites, microscopic examination of stool samples and stool culture can assess infectious enterocolitis, stool for Clostridium Difficile toxins can assess pseudomembranous colitis, and stool guiaic testing checks for blood in the stool.
Blood tests are often informative and relatively inexpensive. A complete blood count and sedimentation rate can suggest an infectious cause. All women of reproductive age with pelvic pain should have sensitive hormone studies to rule out pregnancy. Electrolytes, renal function tests, and liver function tests are also readily available.
Ultrasound evaluation of the pelvis is commonly performed when there is a suspicion of gynecological pathology. The uterine contour is evaluated and the presence, specific location, and number of fibroids (noting degeneration or calcification) as well as the thickness of the endometrial lining should be noted. The adnexae are carefully assessed and the characteristics of ovarian cysts are described (size, hemorrhagic nature, complex features such as internal echogenicity, nodules or septations) and free fluid in the pelvis is measured.
A hysterosalpingogram is considered if there is a suspicion of a uterine anomaly (not uncommon in young adolescent women with severe menstrual or chronic pelvic pain) and sometimes to assess the uterine cavity and patency of the fallopian tubes prior to laparoscopy (to suggest the importance of a concurrent hysteroscopy or to identify a problem with the fallopian tubes that would ideally be discussed preoperatively with the patient).
Magnetic resonance imaging (MRI) is sometimes considered since it provides superb images of soft tissues and can usually identify adenomyosis, clearly outline the location and impact of fibroids on surrounding structures, assess ovarian cysts including suggesting the likelihood of endometriomas or hemorrhagic cysts, determine the presence of uterine anomalies (such as a septate or a bicornuate uterus), and look for urological or orthopedic abnormalities.
Computerized tomography (CT scan) is particularly helpful in assessing the ureters and can track their location preoperatively (which may be important if extensive pelvic adhesions are suspected) or assess the presence of stones (CT is thought to be as sensitive as the usual test, intravenous pyelography or IVP, and provide much more information about the surrounding structures).
A referral for consultation with a Gastrointestinal (GI) physician (who might suggest colonoscopy, barium enema, or GI function testing), a Urologist (who might suggest cystoscopy, IVP, CT scan, or urodynamic testing), or an Orthopedic surgeon (who might suggest X Rays, bone scans, or nerve conduction tests) may be considered based on the findings of the history, physical examination and initial laboratory tests. If the chronic pain syndrome is also suspected, referral for psychological evaluation should be considered.