A 19-year-old woman, gravida 1 para 0, at 39 weeks gestation comes to the hospital due to increasing nausea and vomiting. The nausea began after dinner last night and has progressively worsened. Over the past few hours, she has had 2 episodes of vomiting and constant lower abdominal pain. The patient has had constant clear vaginal discharge over the past 2 days and intermittent vaginal spotting. She reports urinary frequency throughout the pregnancy, but no dysuria or hematuria. The patient was treated for a Chlamydia trachomatis infection in the first trimester; her third-trimester C trachomatis screen was negative. She has no chronic medical conditions and has had no surgeries. Temperature is 39.4 C (103 F), blood pressure is 120/68 mm Hg, and pulse is 100/min. The abdomen is nontender with no rebound or guarding; there is diffuse uterine tenderness. The cervix is 2 cm dilated, the fetal vertex is at -1 station, and nitrazine-positive clear fluid is pooled in the posterior fornix. Fetal heart monitoring shows a rate of 165/min, moderate variability, and no decelerations. Tocometry shows contractions every 10 minutes. Laboratory results are as follows:

Which of the following is the most likely diagnosis in this patient?

Question

A 19-year-old woman, gravida 1 para 0, at 39 weeks gestation comes to the hospital due to increasing nausea and vomiting.  The nausea began after dinner last night and has progressively worsened.  Over the past few hours, she has had 2 episodes of vomiting and constant lower abdominal pain.  The patient has had constant clear vaginal discharge over the past 2 days and intermittent vaginal spotting.  She reports urinary frequency throughout the pregnancy, but no dysuria or hematuria.  The patient was treated for a Chlamydia trachomatis infection in the first trimester; her third-trimester C trachomatis screen was negative.  She has no chronic medical conditions and has had no surgeries.  Temperature is 39.4 C (103 F), blood pressure is 120/68 mm Hg, and pulse is 100/min.  The abdomen is nontender with no rebound or guarding; there is diffuse uterine tenderness.  The cervix is 2 cm dilated, the fetal vertex is at -1 station, and nitrazine-positive clear fluid is pooled in the posterior fornix.  Fetal heart monitoring shows a rate of 165/min, moderate variability, and no decelerations.  Tocometry shows contractions every 10 minutes.  Laboratory results are as follows:
 
Which of the following is the most likely diagnosis in this patient?

Quizplus · Accepted Answer

This patient has an intra-amniotic infection (IAI), also known as chorioamnionitis. This complication is common in patients with premature rupture of the membranes, which occurs before the onset of regular contractions, and in those with prolonged membrane rupture (>18 hours). Patients with IAI typically have nausea, vomiting, and uterine fundal tenderness. The diagnosis is based on the presence of maternal fever plus at least 1 of the following: fetal tachycardia >160/min for at least 10 minutes, maternal leukocytosis, maternal tachycardia, or purulent amniotic fluid. Patients may have an abnormal contraction pattern due to the effect of IAI on uterine muscle contractility. (Choice A) Premature rupture of membranes increases the risk of abruptio placentae, which can present with uterine tenderness. However, patients commonly have heavy vaginal bleeding, nonreassuring fetal heart rate tracing (eg, minimal variability, decelerations), and uterine tachysystole (eg, >5 contractions in a 10 minute period). abruptio placentae nonreassuring fetal heart rate tracing (Choice B) Acute appendicitis typically presents with an acute onset of fever, nausea, anorexia, and right lower quadrant pain. However, during the third trimester patients typically have right upper quadrant pain due to the enlarged uterus causing a shift in the appendiceal location, which is not seen in this patient. (Choice C) Chlamydial cervicitis presents with purulent cervical discharge; there is no associated uterine tenderness. Although this patient was treated for chlamydia in the first trimester, she had a third-trimester negative screen, making this diagnosis unlikely. (Choice E) Pelvic inflammatory disease is an ascending infection uncommon during the third trimester of pregnancy, as thickened cervical mucus provides protection to the uterus from lower pelvic pathogens. Pelvic inflammatory disease is more likely in nonpregnant or first-trimester patients. (Choice F) Viral gastroenteritis presents commonly as an acute-onset diarrheal illness accompanied by other gastrointestinal symptoms such as fever, nausea, vomiting, and abdominal pain. However, patients with viral gastroenteritis do not typically have a fever >38.9 C (102 F) and have diffuse abdominal tenderness rather than uterine tenderness. Educational objective: Intra-amniotic infection (chorioamnionitis) typically presents in patients with premature or prolonged rupture of membranes as maternal fever, maternal and fetal tachycardia, uterine fundal tenderness, and maternal leukocytosis. References: Evaluation and management of women and newborns with a maternal diagnosis of chorioamnionitis: summary of a workshop. (http://www.ncbi.nlm.nih.gov/pubmed/26855098)

A 19-Year-Old Woman, Gravida 1 Para 0, at 39 Weeks