Concomitant Peripartum Hemolysis, Elevated Liver Enzymes, and Low Platelets (HELLP) Syndrome and Pregnancy-Associated Atypical Hemolytic Uremic Syndrome (PA-aHUS): Solving This Diagnostic Dilemma with a Unique Case and Literature Review

Introduction: All peripartum cases of HELLP & PA-aHUS contain the same triad of hemolysis, elevated transaminases & low platelet count. We present a unique case & summary table of the literature to differentiate these conditions. Case Description: A 39y/o G2P0 W with dichorionic twins developed severe preeclampsia with HELLP at 32 weeks gestation. She had hemolytic anemia, Hb 7 gm/dL, haptoglobin <10 mg/dL, plt 51,000, LDH 3543 U/L, AST 830 U/L, schistocytes, & TP/Cr 3.45 g/g. 1 day after delivery she was oliguric, creatinine (sCr) 3.1 mg/dL & potassium 7.2 meq/L, requiring hemodialysis (HD). At day 4 with continued hemolysis & oliguria, plt was 50,000, she had a low C4 9 mg/dL, normal C3 & ADAMTS-13 activity, negative ANA & APL antibodies, & HD continued. After genetic complement tests were sent, Eculizumab (ECU) 900 mg weekly for 4 weeks was started. 3 days after the 1st ECU dose hemolysis resolved, urine protein decreased & HD was stopped. Genetic studies were negative. ECU was continued, 1200 mg every 2 weeks for 5 months (mos), then weaned & stopped at 10 mos, sCr was 0.84 mg/dL with no proteinuria. Table 1 contains the data differentiating HELLP & PA-aHUS. Discussion: We identified PA-aHUS with simultaneous HELLP by the severely elevated LDH > 1832 U/L, sCr > 1.9 mg/dL, persistent hemolysis, low platelet count, & continued AKI 4 d after delivery. In HELLP rapid recovery is noted by day 4 post-partum. Early diagnosis of PA-aHUS in this patient lead to a quick start of ECU & continued for 10 mos despite negative complement mutations. This allowed full renal & hematologic recovery & prevention of renal cortical necrosis, a dire outcome in PA-aHUS. Patients with HELLP persisting for > 4 d should receive ECU. Table 1 - Parameter NORMAL PREGNANCY PREECLAMPSIA HELLP PA-aHUS Hemolysis No No 100% 100% Platelet Count 10^3/μL >150 100-149 <150 <100 *LDH IU/L NL Mild increase 600-1832 >1832 *Serum Creatinine mg/dL <0.8 0.8-1.5 <1.9 >1.9 C3 High High Normal Low (30-60%) C4 High High Low (90%) NL Complement Mutations No Rare 6-45% 55-81% Stage 3 AKI No 4% 11% 90% Recovery N/A After Delivery Within 4 days postpartum Persistent postpartum *Burwick et al, Hypertension. 2021;78(3):760-768