A 26-year-old woman is brought to the emergency department due to lower abdominal pain for the past 2 days. She reports intractable nausea and vomiting over the last day, but has no fever, chills, sick contacts, or diarrhea. She recently had an hCG injection in preparation for an egg retrieval for infertility treatment. The patient has a history of polycystic ovarian syndrome and has had no surgeries. Family history is noncontributory. She takes a daily prenatal vitamin and does not use tobacco, alcohol, or illicit drugs. Blood pressure is 90/50 mm Hg and pulse is 110/min. BMI is 35 kg/m². Physical examination shows a distended abdomen with normal bowel sounds and diffuse lower abdominal tenderness to deep palpation. There is no rebound, guarding, or costovertebral angle tenderness. Urine pregnancy test is positive. Transvaginal ultrasound shows bilateral ovarian enlargement with multiple cysts measuring up to 8 x 8 cm and intraabdominal fluid consistent with ascites. Doppler shows preserved blood flow to both ovaries. Which of the following is the most likely cause of this patient's condition?

Question

Quizplus · Accepted Answer

Explanation: 11ec2b69_befd_fe80_8f63_afb260c4e615_MD0005_00 This patient is most likely experiencing ovarian hyperstimulation syndrome (OHSS), a rare but potentially devastating complication of ovulation induction. Ovulation induction agents (eg, hCG injections) are used to stimulate multiple follicle production in preparation for egg retrieval in patients undergoing in vitro fertilization (IVF) for infertility treatment. When the follicles undergo artificial maturation via the hCG injection, the ovaries overexpress vascular endothelial growth factor (VEGF), resulting in increased vascular permeability and capillary leakage. This increased permeability causes a fluid shift to the extravascular space (eg, third spacing). Patients with OHSS typically present 1-2 weeks after ovulation induction treatment with nausea, vomiting, abdominal pain, and bilaterally enlarged ovaries with multiple follicles. Other features include rapid weight gain, dyspnea, and oliguria/anuria. In these patients, the increased extravascular volume results in ascites, pleural and pericardial effusions, and electrolyte imbalances. The concomitant intravascular volume depletion causes hemoconcentration, hypercoagulability, and hypovolemic shock in severe cases. Complications of OHSS include renal failure, acute respiratory distress syndrome, disseminated intravascular coagulation/thromboembolism, and death. Initial workup includes complete blood count, serum electrolytes, coagulation studies, and β-hCG levels. Treatment includes correcting electrolyte imbalances, performing therapeutic paracentesis or thoracentesis, and monitoring fluid balances. (Choice A) Ruptured ectopic pregnancy may cause abdominal pain with a positive pregnancy test; however, ultrasound shows a unilateral, complex, adnexal mass rather than bilateral, enlarged ovaries. The hCG injection for IVF causes a positive urine pregnancy test; however, it is a false-positive result. (Choice B) A normal course of IVF may cause mild symptoms, including breast tenderness, bloating, abdominal cramping, and constipation. (Choice D) Ovarian torsion may occur in patients with OHSS due to ovarian enlargement. However, the typical presentation is a sudden onset of unilateral pelvic pain and absent Doppler flow to the ovary. This patient has preserved blood flow to the ovaries, making this diagnosis less likely. (Choice E) Patients with a ruptured ovarian cyst can have sudden onset of pelvic pain and free fluid on ultrasound; however, there is an associated acute abdomen (eg, rebound, guarding) from hemoperitoneum, and acute blood loss anemia (not hemoconcentration). Educational objective: Ovarian hyperstimulation syndrome is a complication of ovulation induction therapy for infertility. Patients have bilateral enlarged ovaries, ascites, hemoconcentration, hypercoagulability, and possible multiorgan failure. References: A review on ovarian hyperstimulation syndrome (OHSS) management strategies. (http://www.ncbi.nlm.nih.gov/pubmed/28322539) Volume expanders for the prevention of ovarian hyperstimulation syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/27577848)

A 26-Year-Old Woman Is Brought to the Emergency Department Due