A 16-year-old girl comes to the office due to recurrent, intermittent lower abdominal pain. The pain typically begins the day prior to the onset of menses and subsides on the second day of bleeding. She has associated nausea and diarrhea during this time but has no constipation or pain with defecation. These symptoms began 5 months ago and have progressively worsened, causing the patient to miss 2 days of school last month. Menarche was at age 13 and her menses were irregular until 6 months ago; now menses occur every 28 days with 4 to 5 days of moderate bleeding. The patient recently became sexually active and uses condoms for contraception. Her last menstrual period was 2 weeks ago. Vital signs are normal. On speculum examination, a small amount of physiologic discharge is noted throughout the vaginal vault, and the cervix is nonfriable. The uterus is small, mobile, and nontender. Pregnancy test is negative. Which of the following is the most likely cause of this patient's pain?

Question

A 16-year-old girl comes to the office due to recurrent, intermittent lower abdominal pain.  The pain typically begins the day prior to the onset of menses and subsides on the second day of bleeding.  She has associated nausea and diarrhea during this time but has no constipation or pain with defecation.  These symptoms began 5 months ago and have progressively worsened, causing the patient to miss 2 days of school last month.  Menarche was at age 13 and her menses were irregular until 6 months ago; now menses occur every 28 days with 4 to 5 days of moderate bleeding.  The patient recently became sexually active and uses condoms for contraception.  Her last menstrual period was 2 weeks ago.  Vital signs are normal.  On speculum examination, a small amount of physiologic discharge is noted throughout the vaginal vault, and the cervix is nonfriable.  The uterus is small, mobile, and nontender.  Pregnancy test is negative.  Which of the following is the most likely cause of this patient's pain?

Quizplus · Accepted Answer

Explanation: 11ec25c8_d9b6_b76b_bc81_cfc0350a2c3a_MD0003_00 This patient's regular, painful menses and normal pelvic examination are consistent with primary dysmenorrhea. This condition is common in adolescents after the establishment of ovulatory menstrual cycles. During menses, the endometrium produces and releases prostaglandins, which stimulates uterine contractions and promotes endometrial sloughing. In primary dysmenorrhea, patients have increased endometrial prostaglandin production, which causes uterine hypercontractility and hypertonicity and resultant ischemia. The cumulative effect of primary dysmenorrhea results in the classic manifestations of: cramping, midline lower abdominal pain that begins 1-2 days prior to menses and radiates to the lower back and thighs (uterine hypertonicity and ischemia). systemic symptoms such as nausea, vomiting, and diarrhea (prostaglandin-induced stimulation of the gastrointestinal tract). First-line treatment of primary dysmenorrhea is with nonsteroidal anti-inflammatory drugs, which inhibit prostaglandin synthesis. (Choice A) Adenomyosis can cause dysmenorrhea due to the endometrial stroma and glands within the uterine muscle; however, this intramuscular endometrial tissue causes a symmetrically enlarged, tender ("globular") uterus, which is not seen in this patient. In addition, it typically occurs in women age >40. (Choice B) Endometriosis, endometrial gland implants outside the uterus, causes dysmenorrhea. However, patients typically have pelvic pain throughout menses (rather than resolving within 1-2 days after onset) that may persist beyond menses (ie, chronic pelvic pain). (Choice D) Ovarian torsion, intermittent compression of the ovarian vessels, can cause intermittent pain; however, the pain is usually unilateral and unrelated to menses. Ovarian torsion (Choice E) Mittelschmerz pain, caused by peritoneal inflammation from ovarian follicle rupture, occurs during ovulation (approximately 2 weeks prior to menses rather than during menses). ovulation (Choice F) Endometritis, a polymicrobial infection within the endometrial cavity, can present with chronic pelvic pain; however, patients have abnormal uterine bleeding (eg, postcoital or intermenstrual bleeding) rather than dysmenorrhea. In addition, patients typically have cervical motion tenderness or uterine tenderness. Educational objective: Primary dysmenorrhea occurs due to increased endometrial prostaglandin production during menses that causes uterine hypercontractility and hypertonicity. This results in the classic findings of midline lower abdominal pain with associated systemic symptoms (eg, nausea, vomiting, diarrhea). First-line treatment is with nonsteroidal anti-inflammatory drugs. References: Primary dysmenorrhea in adolescents: prevalence, impact and recent knowledge. (http://www.ncbi.nlm.nih.gov/pubmed/26841639) ACOG committee opinion no. 760: dysmenorrhea and endometriosis in the adolescent. (http://www.ncbi.nlm.nih.gov/pubmed/30461694) Primary dysmenorrhea: advances in pathogenesis and management. (http://www.ncbi.nlm.nih.gov/pubmed/16880317)

A 16-Year-Old Girl Comes to the Office Due to Recurrent