Critically appraise the diagnosis and management of early-onset pre-eclampsia with severe features

In one line

Early-onset pre-eclampsia with severe features (severe features before 34 weeks) is a maternal multi-organ disease whose only cure is delivery — the whole craft is buying fetal maturity by expectant management while controlling blood pressure, giving magnesium sulphate for seizure prophylaxis, and recognising the precise moment when maternal or fetal deterioration makes continuing the pregnancy more dangerous than prematurity.

This chapter assumes the diagnostic groundwork in pre-eclampsia & HELLP basics and hypertension in pregnancy; it spends its words on the appraisal and the judgement calls. Prevention is covered in Pre-eclampsia screening and aspirin prophylaxis and the drug-by-drug argument in Hypertension in pregnancy antihypertensives.

Why this matters in South Africa

Hypertensive disorders are consistently among the top causes of maternal death in the Saving Mothers reports, and the deaths cluster around two avoidable end-points: intracranial haemorrhage from uncontrolled severe hypertension, and pulmonary oedema from iatrogenic fluid overload. Both are failures of the early, cheap, protocol-driven steps — not of heroic tertiary care. Early-onset disease additionally collides with the SA reality that neonatal intensive care is scarce and unevenly distributed, so the "buy time" calculus that a high-income unit takes for granted is, in a district hospital, often a "stabilise and transfer" decision instead. Both the protocol that prevents the death and the system-level call about where the woman should be have to be right.

Pathophysiology — why early-onset disease behaves differently

Pre-eclampsia is best understood as a two-stage placental disease, and the early-onset phenotype is the one that maps most cleanly onto that model.

• Stage 1 — defective spiral-artery remodelling. In normal pregnancy, extravillous trophoblast invades and converts the maternal spiral arteries into wide, low-resistance, high-flow conduits. In pre-eclampsia this conversion is incomplete: the arteries stay narrow and muscular, giving a placenta that is chronically under-perfused and subject to ischaemia–reperfusion injury. Early-onset disease is the placental phenotype — poor placentation dominates, which is exactly why it travels with fetal growth restriction and abnormal umbilical-artery Dopplers. (Late-onset disease, by contrast, is more often a maternal-constitutional phenotype with a relatively normal placenta.)
• Stage 2 — the maternal syndrome. The ischaemic placenta releases anti-angiogenic factors into the maternal circulation: soluble fms-like tyrosine kinase-1 (sFlt-1), which scavenges circulating VEGF and placental growth factor (PlGF), and soluble endoglin (sEng). The result is widespread endothelial dysfunction — the unifying lesion that explains every organ manifestation: vasoconstriction (hypertension), increased vascular permeability (oedema, proteinuria, pulmonary oedema), a procoagulant endothelium (microangiopathy, HELLP), and impaired autoregulation in the cerebral circulation (eclampsia, posterior reversible encephalopathy). This is why the sFlt-1/PlGF ratio is biologically meaningful and not just a number — it indexes the driver of the maternal syndrome.

The practical corollaries follow from mechanism: the disease is multi-system (so investigate every organ, not just the BP), it is progressive and unpredictable (so a normal set of bloods now does not exclude HELLP in six hours), and it is only cured by removing the placenta (so every management plan ends, sooner or later, in delivery).

Assessment

The diagnosis is not the difficulty — defining the severe phenotype and tracking its trajectory is. Severe features (ACOG 2020) are: BP ≥160/110 on two occasions ≥4 h apart (or once if treatment is started sooner); platelets <100 × 10⁹/L; transaminases >2× upper limit of normal or severe RUQ/epigastric pain; creatinine >1.1 mg/dL (≈97 µmol/L) or doubling; pulmonary oedema; or new cerebral/visual symptoms. Proteinuria quantity is not a severity marker and is not needed to diagnose pre-eclampsia once organ involvement is present.

History — the symptoms that signal end-organ involvement, not just "feeling unwell":

• Headache unresponsive to simple analgesia — cerebral vasogenic oedema; the herald of eclampsia.
• Visual disturbance — scintillations, scotomata, blurring or transient cortical blindness (occipital oedema/PRES).
• Epigastric or right-upper-quadrant pain — stretching of the hepatic (Glisson's) capsule from periportal haemorrhage/oedema; the symptom of HELLP and a warning of subcapsular haematoma.
• Breathlessness or orthopnoea — pulmonary oedema, the second great killer.
• Reduced fetal movements — placental insufficiency.
• Anchor the gestation precisely: every subsequent decision pivots on it.

Examination — organ by organ:

• Cardiovascular — confirmed severe BP (correct cuff size, seated, arm at heart level), and signs of overload (raised JVP, gallop).
• Respiratory — respiratory rate (>24 is an early sign of pulmonary oedema), oxygen saturation, basal crepitations.
• Neurological — hyperreflexia and sustained clonus (>3 beats) signal cortical irritability and heighten eclampsia risk; assess conscious level.
• Abdominal — RUQ/epigastric tenderness; symphysis–fundal height against the growth chart.
• Fetal — CTG if viable, and a clinical estimate of liquor and presentation.

Investigations and what each is for:

• FBC + smear — thrombocytopenia (consumption), and a haemolytic film (schistocytes, fragments) for HELLP. A falling platelet trend matters more than a single value.
• U&E / creatinine — acute kidney injury from renal hypoperfusion/glomerular endotheliosis; oliguria.
• ALT/AST and LDH — transaminitis and haemolysis. The HELLP trajectory is rising LDH and transaminases with falling platelets; repeat 6–12-hourly, because a single normal set does not exclude evolving disease.
• Coagulation (PT/aPTT/fibrinogen) — only if platelets are very low, there is bleeding, or abruption/DIC is suspected; fibrinogen <2 g/L in this setting is ominous.
• Uric acid — rises with disease but is a weak, non-diagnostic marker; do not hang management on it.
• Fetus — dating (or EFW if undated), umbilical-artery Doppler, and serial growth. Early-onset disease is the placental phenotype, so FGR and absent or reversed end-diastolic flow are common and shift the delivery calculus; a ductus venosus assessment helps time delivery at the extremes of viability.

Think about the differential of microangiopathy, because the management diverges: HELLP (the common one), acute fatty liver of pregnancy (hypoglycaemia, marked coagulopathy, raised ammonia/bilirubin), and the thrombotic microangiopathies TTP and atypical HUS (more haemolysis and renal failure, less hepatic and BP derangement, and crucially do not resolve with delivery — they need plasma exchange or complement blockade). Getting this wrong delays the right treatment.