Differential Diagnosis
- Single most likely diagnosis
- Preterm labor with possible chorioamnionitis: This diagnosis is likely due to the patient's symptoms of increasing nausea and vomiting, lower abdominal pain, constant clear vaginal discharge, and intermittent vaginal spotting. The presence of a fever (39.4 C), uterine tenderness, and an elevated leukocyte count (18,500/mm3) also support this diagnosis. The nitrazine-positive clear fluid in the posterior fornix suggests ruptured membranes, which increases the risk of chorioamnionitis.
- Other Likely diagnoses
- Urinary tract infection: Although the patient reports urinary frequency throughout the pregnancy, the absence of dysuria or hematuria makes this diagnosis less likely. However, the elevated leukocyte count and the presence of a fever could still be indicative of a urinary tract infection.
- Placental abruption: The patient's lower abdominal pain and vaginal spotting could be indicative of placental abruption. However, the absence of severe abdominal pain, rebound tenderness, and fetal distress makes this diagnosis less likely.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Uterine rupture: Although the patient is not reporting severe abdominal pain, uterine rupture is a life-threatening condition that must be considered, especially in the presence of uterine tenderness and a fever.
- Amniotic fluid embolism: This rare but deadly condition can present with sudden onset of symptoms such as nausea, vomiting, and abdominal pain. The presence of a fever and uterine tenderness could be indicative of an amniotic fluid embolism.
- Rare diagnoses
- Listerial infection: Although the patient was treated for a Chlamydia trachomatis infection in the first trimester, a listerial infection could still be present, especially in the presence of a fever and uterine tenderness.
- Intra-amniotic infection: This rare condition can present with symptoms such as fever, uterine tenderness, and fetal tachycardia. The presence of a fever and an elevated leukocyte count could be indicative of an intra-amniotic infection.