HELLP Syndrome Diagnostic Criteria
Mississippi triple-class system for HELLP syndrome (Martin 1999): LDH ≥ 600 IU/L with platelet and transaminase thresholds. Class 1 is the most severe.
Score interpretation
Platelets, transaminases and LDH do not meet a Mississippi class. Values short of a class (e.g. platelets ≤ 100 ×10⁹/L with AST/ALT 40–69 IU/L) can be partial or evolving HELLP syndrome — it is not excluded.
→ If pre-eclampsia features present, manage per NICE NG133 and repeat bloods. Consider TTP, HUS, acute fatty liver of pregnancy if haemolysis present without hypertension.
Platelets ≤ 50 ×10⁹/L, AST or ALT ≥ 70 IU/L, LDH ≥ 600 IU/L.
→ IMMEDIATE delivery if ≥ 34 weeks or maternal/fetal compromise. Adults: MgSO₄ for seizure prophylaxis (4g IV bolus then 1g/h). Children: use a children's formulary. Antihypertensives: IV labetalol or hydralazine for SBP ≥ 160. Blood bank: crossmatch 4 units. Platelet transfusion if < 20 or < 50 pre-CS. ICU involvement. Neonatology present at delivery.
Platelets > 50 to ≤ 100 ×10⁹/L, AST or ALT ≥ 70 IU/L, LDH ≥ 600 IU/L.
→ IMMEDIATE delivery if ≥ 34 weeks or maternal/fetal compromise. Adults: MgSO₄ for seizure prophylaxis (4g IV bolus then 1g/h). Children: use a children's formulary. Antihypertensives: IV labetalol or hydralazine for SBP ≥ 160. Blood bank: crossmatch 4 units. Platelet transfusion if < 20 or < 50 pre-CS. ICU involvement. Neonatology present at delivery.
Platelets > 100 to ≤ 150 ×10⁹/L, AST or ALT ≥ 40 IU/L, LDH ≥ 600 IU/L.
→ Admit to obstetric HDU. IV access × 2. Bloods: FBC, LFTs, LDH, clotting, urate, U&E every 6–12h. Antihypertensives if BP ≥ 150/100. Corticosteroids for fetal lung maturity if < 34 weeks. Consider delivery plan.
Interpretation bands for the HELLP. Apply clinical judgement and local guidance.
References
- Martin JN Jr, Rinehart BK, May WL, et al. The spectrum of severe preeclampsia: comparative analysis by HELLP (hemolysis, elevated liver enzyme levels, and low platelet count) syndrome classification. Am J Obstet Gynecol. 1999;180(6):1373-1384.
- NICE NG133. Hypertension in pregnancy: diagnosis and management. 2019.
Related
Curated clinical cross-links plus same-class fallbacks.
- Labetalol (IV — Hypertensive Emergency) · Combined Alpha-1 and Beta-Adrenergic Blocker
- Labetalol (IV — Hypertensive Emergency) · Combined alpha and beta blocker
- Magnesium Sulphate (Obstetric — Eclampsia/Neuroprotection) · Anticonvulsant / Neuroprotectant
- Hydralazine · Direct-Acting Vasodilator — Hypertensive Emergency / Chronic Hypertension
- Sodium Nitroprusside · Direct Vasodilator (NO Donor) — Hypertensive Emergency / Aortic Dissection
- Tenecteplase · Cardiovascular Emergency
- Spinal Anaesthesia Hypotension Management · AAGBI; ASA
- Pre-Eclampsia / Eclampsia in ED · NICE NG133; RCOG Green-top 10A
- Suspected Ectopic Pregnancy · NICE NG126; RCOG Green-top 21
- Polycystic Ovary Syndrome (PCOS) · International PCOS Guideline 2023; NICE CKS
- Pre-eclampsia Management · NICE NG133 2019
- Ectopic Pregnancy · NICE CG154 / RCOG GTG 21
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.
