What is the most likely diagnosis for a 41-week gestation pregnant woman with severe headaches, bilateral lower-extremity pitting edema, clonus, hypertension (elevated blood pressure), thrombocytopenia (low platelet count), impaired liver function (elevated liver enzymes), and proteinuria (high total urine protein-creatinine ratio)?

HELLP Syndrome

This patient has HELLP syndrome, characterized by the classic triad of hemolysis (elevated LDH 722 units/L), elevated liver enzymes (ALT 88 units/L), and low platelets (52,000/mm³), occurring in the context of hypertension at 41 weeks gestation. 1

Diagnostic Reasoning

The clinical presentation definitively points to HELLP syndrome based on the following laboratory constellation:

• Hemolysis indicators: LDH elevated at 722 units/L (markedly elevated) and hemoglobin 9.6 mg/dL (anemia from hemolysis) 1
• Elevated liver enzymes: ALT 88 units/L (>2x normal upper limit) 1
• Low platelets: 52,000/mm³ (severe thrombocytopenia, well below 100,000/mm³ threshold) 1
• Hypertension: BP 160/105 mm Hg (severe range) 1
• Neurological features: Severe headaches and clonus indicating CNS involvement 1

Why Not the Other Diagnoses

Preeclampsia with severe features (Option D) is technically present, but the specific constellation of hemolysis, elevated liver enzymes, and severe thrombocytopenia defines HELLP syndrome as the more precise diagnosis. 1 HELLP syndrome is considered part of the preeclampsia spectrum but represents a more serious manifestation requiring immediate recognition. 1

Important caveat: The proteinuria is relatively modest (protein-creatinine ratio 0.25, which is below the typical 0.3 threshold for significant proteinuria). 1 However, proteinuria is not required for HELLP syndrome diagnosis—approximately 10-15% of HELLP cases present without significant proteinuria. 2 The diagnosis rests on the laboratory triad plus hypertension and symptoms. 1

Acute Fatty Liver of Pregnancy (Option A) would typically present with more profound liver dysfunction, hypoglycemia, coagulopathy beyond just thrombocytopenia, and often jaundice—features not present here. 1

COVID-19 (Option B) does not explain the specific laboratory pattern of hemolysis, elevated liver enzymes, and thrombocytopenia in this constellation. 1

SLE flare (Option E) could theoretically cause similar findings, but the acute onset at 41 weeks gestation in the context of hypertension and the specific HELLP triad makes this diagnosis far less likely without prior SLE history. 1

Immediate Management Required

This patient requires immediate treatment and delivery per international guidelines. 1

• Magnesium sulfate for seizure prophylaxis given severe features (neurological symptoms with clonus and severe headaches) 1, 2
• Antihypertensive therapy to maintain BP <160/110 mm Hg using labetalol, nifedipine, or methyldopa 1
• Expedited delivery at 41 weeks gestation with HELLP syndrome—this is non-negotiable 1
• Platelet transfusion may be needed if platelets <50,000/mm³ and delivery is imminent or for neuraxial anesthesia 1

Critical Pitfall to Avoid

Do not delay delivery waiting for proteinuria to worsen or other features to develop. 1 The combination of severe thrombocytopenia, hemolysis, elevated liver enzymes, hypertension, and neurological symptoms at term mandates immediate delivery after maternal stabilization. 1 Approximately 20% of HELLP cases occur postpartum, so close monitoring for 48-72 hours after delivery is essential. 2