Preeclampsia with Severe Features
Obstetrics & Gynecology
Illness script · Obstetrics & Gynecology
Preeclampsia with Severe Features
Hypertensive disorder of pregnancy ≥20 weeks with end-organ damage (BP ≥160/110, proteinuria ± severe features).
This illness script for Preeclampsia with Severe Features covers predisposing factors, classic presentation, mechanism, workup, management, and the clinical pivots that separate it from look-alikes—written for USMLE Step 1 and clerkship reasoning.
01
Predisposing factors
- Nulliparity is the strongest risk factor
- Chronic hypertension, diabetes, renal disease, obesity
- Prior preeclampsia (recurrence risk ~15–20%)
- Multiple gestation, molar pregnancy
- Age <18 or >35; African American race; autoimmune disease (SLE, antiphospholipid syndrome)
02
Presentation
- BP ≥160/110 on two readings ≥4 hours apart after 20 weeks
- Severe headache (frontal), visual changes (scotomata, blurring), RUQ/epigastric pain
- Pulmonary edema, new-onset seizure (eclampsia), altered mental status
- Thrombocytopenia (<100k), elevated LFTs (≥2× normal), rising creatinine (>1.1)
- Fetal growth restriction on exam; hyperreflexia with clonus on neuro exam
- Onset can be remote from term (early-onset <34 wks = more severe disease)
03
Pathophysiology
- Abnormal placentation → shallow trophoblast invasion → inadequate spiral artery remodeling
- Uteroplacental ischemia → systemic endothelial dysfunction and vasospasm
- Vasoconstriction → hypertension, proteinuria (glomerular endotheliosis), end-organ ischemia
- Imbalance: ↑ antiangiogenic sFlt-1, ↓ proangiogenic VEGF/PlGF
04
Diagnostics
- BP ≥160/110 (severe threshold) + any severe feature = diagnosis
- Proteinuria ≥300 mg/24h or PCr ≥0.3 (not required if severe features present)
- CBC: thrombocytopenia; CMP: elevated creatinine, LFTs; LDH elevated
- HELLP syndrome: Hemolysis + Elevated LFTs + Low Platelets — a severe feature variant
- Fetal monitoring: NST, BPP, Doppler; no single biomarker is gold standard clinically
05
Management
- Definitive treatment: delivery (only cure); timing depends on gestational age
- ≥37 weeks (or ≥34 weeks with severe features): deliver promptly
- <34 weeks: consider corticosteroids for fetal lung maturity then deliver
- Acute BP control: IV labetalol or IV hydralazine or oral nifedipine (target <160/110 urgently)
- Seizure prophylaxis: IV/IM magnesium sulfate (also first-line treatment for eclampsia)
- Magnesium toxicity antidote: calcium gluconate; avoid MgSO4 in myasthenia gravis
06
Clinical pivots
How to separate this script from the look-alikes that show up on exams and on the wards.
Chronic Hypertension with Superimposed Preeclampsia
Pre-existing HTN before 20 weeks; superimposed = acute end-organ damage added on top
Gestational Hypertension
BP ≥140/90 after 20 weeks but NO proteinuria and NO severe features
HELLP Syndrome
Hemolysis + elevated LFTs + low platelets; may present without severe hypertension or headache
Eclampsia
New-onset grand mal seizure in preeclampsia patient; treat with MgSO4 not antiepileptics
Keep reading
Full library- Placental AbruptionPremature separation of a normally implanted placenta from the uterine wall before delivery, causing hemorrhage and fetal compromise.
- Pulmonary EmbolismAcute obstruction of pulmonary arterial circulation, most often by thrombus from deep veins, causing hypoxia and right heart strain.
Educational use only. This illness script is a study framework, not medical advice. Confirm decisions with current guidelines and your clinical supervisors.