A 32-year-old woman at 40 weeks gestation presents to the labor and delivery unit with complaints of fever, chills, and lower abdominal pain. Her vital signs are: temperature 101.8°F (38.8°C), pulse 110 bpm, respirations 22/min, and blood pressure 130/85 mmHg. The fetal heart rate shows baseline tachycardia at 170 bpm with minimal variability. Which assessment finding would be most indicative of chorioamnionitis?
1Decreased white blood cell count with lymphocytosis
2Foul-smelling, purulent amniotic fluid during vaginal examination✓ 정답
3Decreased fetal movement reported by the mother
4Presence of protein in the urine sample
해설
Foul-smelling, purulent amniotic fluid is the most characteristic sign of chorioamnionitis, indicating active infection. Other findings are less specific or not typical of chorioamnionitis.
The scenario describes a term pregnancy complicated by maternal fever, tachycardia, and fetal tachycardia with minimal variability. This clinical picture raises immediate concern for intrauterine infection. The condition historically termed chorioamnionitis is now more precisely referred to as Intrauterine Inflammation or Infection or both (Triple-I), a redefinition aimed at improving diagnostic accuracy and management strategies for both mother and neonate [2]. The maternal systemic response—fever and tachycardia—coupled with the fetal response of tachycardia, reflects the fetal inflammatory response syndrome (FIRS), which is a marker of severe disease and is associated with adverse neonatal outcomes .
Analyzing the Answer Choices
The question asks for the assessment finding most indicative of Triple-I/chorioamnionitis. The clinical diagnosis is primarily based on maternal fever and at least one other clinical sign, such as fetal tachycardia, maternal leukocytosis, or purulent cervical discharge. Direct visualization or detection of infected amniotic fluid provides strong, confirmatory evidence of the intra-amniotic infection process.
- Option 1: Decreased white blood cell count with lymphocytosis. This is incorrect. The expected hematologic response in chorioamnionitis is maternal leukocytosis (elevated white blood cell count), not a decrease. Lymphocytosis is not a typical feature of this acute bacterial infection.
- Option 2: Foul-smelling, purulent amniotic fluid during vaginal examination. This is the correct answer. Purulent, foul-smelling amniotic fluid is a direct clinical sign of intra-amniotic infection. It represents the presence of bacteria and inflammatory exudate within the amniotic cavity, which is the pathophysiological hallmark of chorioamnionitis. This finding is a highly specific indicator of the condition.
- Option 3: Decreased fetal movement reported by the mother. While a concerning symptom that requires immediate evaluation, decreased fetal movement is a nonspecific sign of fetal compromise. It can be caused by various conditions, including uteroplacental insufficiency, and is not a defining or specific diagnostic criterion for chorioamnionitis.
- Option 4: Presence of protein in the urine sample. Proteinuria is a key diagnostic feature of preeclampsia, not chorioamnionitis. Although a patient can have both conditions, proteinuria is not part of the diagnostic criteria for intrauterine infection and does not directly indicate its presence.
Connecting Clinical Signs to Pathophysiology and Outcomes
The clinical diagnosis of chorioamnionitis is a critical trigger for immediate intervention, including intravenous antibiotic administration, as prompt management is essential to mitigate maternal and neonatal risks . The presence of purulent fluid confirms the diagnosis at the bedside and explains the systemic and fetal responses observed. The maternal fever (101.8°F / 38.8°C) and tachycardia (110 bpm) are systemic manifestations of infection. The fetal tachycardia (170 bpm) with minimal variability is a direct consequence of the fetal inflammatory response to the infectious process. Research has identified that clinical chorioamnionitis at term is associated with a spectrum of histological severity, and the most severe forms are independently linked to a higher risk of NICU admission for the neonate . The Kaiser sepsis score is one tool used postnatally to evaluate newborns for early-onset sepsis, a known independent risk linked to chorioamnionitis [2]. Therefore, recognizing the most specific clinical sign, such as purulent amniotic fluid, allows for the earliest possible diagnosis and the rapid initiation of interprofessional care to improve outcomes .
References (research sources)
[2]
Association of Kaiser sepsis score with confirmed intrauterine infection and inflammation (Triple-I) in clinical chorioamnionitis: a retrospective cohort study.Research articleRafferty S, Heerema-McKenney A, Kasaris M, Smith A, Gordon-Ocejo G, Aly H, Das A. (2025) · DOI: 10.1186/s40748-025-00226-7
Clinical Guideline for Suspected Intra-amniotic Infection (Triple-I)
When a term patient presents with maternal fever (≥38.0°C/100.4°F) and signs such as fetal tachycardia, the primary assessment should focus on confirming intra-amniotic infection. A sterile speculum examination to visualize the cervix and assess for purulent or foul-smelling fluid is critical.
Key Diagnostic Steps
Maternal Assessment: Monitor vital signs for fever, tachycardia, and uterine tenderness. Obtain CBC for leukocytosis.
Fetal Surveillance: Continuous electronic fetal monitoring to evaluate baseline heart rate, variability, and decelerations. Fetal tachycardia with minimal variability suggests FIRS.
Amniotic Fluid Evaluation: Perform a sterile speculum exam if membranes are ruptured. Purulent or malodorous fluid is a confirmatory sign. Amniocentesis for culture and glucose may be considered if diagnosis is uncertain.
Immediate Management
Once Triple-I is diagnosed, prompt initiation of broad-spectrum intravenous antibiotics (e.g., ampicillin and gentamicin) and delivery planning are essential. Intrapartum antibiotics reduce maternal and neonatal morbidity. Cesarean delivery is reserved for standard obstetric indications, not solely for the infection.
Nursing Considerations
Notify the provider immediately upon identifying maternal fever and fetal tachycardia.
Prepare for potential neonatal resuscitation, as the infant is at risk for sepsis and respiratory distress.
Document the character of amniotic fluid (color, odor, consistency) accurately.
Administer prescribed antipyretics and antibiotics promptly, and monitor maternal-fetal response.
Triple-I — Intrauterine Inflammation or Infection or both; the updated terminology replacing chorioamnionitis to improve diagnostic accuracy.
Fetal Inflammatory Response Syndrome (FIRS) — A fetal systemic inflammatory response, often indicated by fetal tachycardia, associated with intrauterine infection and adverse neonatal outcomes.
Purulent amniotic fluid — Amniotic fluid containing pus, a direct and strong clinical sign of intra-amniotic infection.
Leukocytosis — An elevated white blood cell count, a common maternal systemic response to infection such as chorioamnionitis.
Minimal variability — An abnormal fetal heart rate pattern with little fluctuation, indicating possible fetal hypoxia or central nervous system depression, often seen in FIRS.