Approach Considerations
Perform a urine pregnancy test. If the pregnancy test is positive, make sure to rule out an ectopic pregnancy. Evaluate for ovarian torsion before discharge. If a diagnosis of bleeding ruptured ovarian cyst is considered, make sure the hemoglobin level is stable before discharging the patient. It is appropriate to admit the patient for observation and pain control.
Perform a diagnostic laparoscopy and/or laparotomy if the patient is hemodynamically unstable or if a specific diagnosis is unclear, yet a definitive diagnosis is necessary.
A study by Shiota et al indicated that C-reactive protein (CRP) levels can be used preoperatively to differentiate a ruptured ovarian cyst from ovarian torsion. In a retrospective evaluation of 98 patients diagnosed with a benign ovarian cyst, it was found that 21 patients with a ruptured cyst and 77 patients with ovarian torsion had mean preoperative CRP levels of 6.6 and 0.9 mg/dL, respectively; the mean size of the ovarian cysts also differed significantly between the two groups (6.7 cm and 9.7 cm, respectively). The investigators mentioned another study, however, that indicated that patients with ovarian torsion who present over 10 hours after the onset of acute abdomen with elevated CRP levels are at risk of necrosis. They suggested, therefore, that by taking into account imaging findings, CRP levels, and time of acute abdomen onset, clinicians can preoperatively differentiate ovarian cyst rupture from ovarian torsion. [11]
Tanaka et al suggest that plasma D-dimer levels may be markers for endometriotic ovarian cyst rupture. [12] In their study of 6 patients with emergent endometriotic cyst rupture and 16 control patients with unruptured endometriotic cysts, significantly elevated plasma D-dimer levels were seen in the group with the ruptured cysts. The investigators also noted that differences in white blood cell count and serum CRP levels between the two groups were statistically significant. [12]
Laboratory Studies
Serum or urine pregnancy testing should be performed. In the case of a positive result, the patient should be evaluated for ectopic pregnancy. If concerned regarding possible hemorrhage, monitor the hematocrit (serially, if necessary) to ensure there is no continued bleeding.
If the diagnosis is unclear, urinalysis should be performed to identify a possible urinary tract infection or renal or bladder stones. Blood, urine, and cervical cultures may also be indicated rule out pelvic inflammatory disease or urinary tract infections.
Blood type and cross-match are indicated in patients with significant peritoneal signs or hemodynamic instability, because such patients may require surgical intervention or blood transfusion.
A case study of 34-year-old woman who presented with severe bilateral lower quadrant abdominal pain after sexual intercourse found that even though no evidence of cysts were observed on CT or intraoperatively, histopathological examination revealed a hemorrhagic corpus luteal cyst. [13]
Imaging Studies
Ultrasonography is the preferred imaging modality for assessing gynecologic structures, given its low cost, availability, and sensitivity in recognizing adnexal cysts and hemoperitoneum. [14, 15, 16] Despite this, there remain instances in which the ultrasound findings are nonspecific, particularly after rupture and decompression of a cyst in the setting of apparent physiologic levels of fluid in the pelvis.
If ultrasound yields ambiguous results in a patient with significant pain, computed tomography (CT) of the pelvis with contrast should be performed. CT features of corpus luteum cysts have been previously described. [17, 18, 19]
Although commonly performed in the past, culdocentesis has been largely abandoned in favor of ultrasonography and CT scanning, as both can readily identify fluid collections in the cul-de-sac. Culdocentesis is still acceptable, however, in locations where imaging is not available.