HELLP syndrome

HELLP syndrome is considered by many to be a severe form of preeclampsia (sometimes called "atypical preeclampsia"). However, it has a different definition characterized by hemolysis (H), also expressed as microangiopathic hemolytic anemia, elevated liver enzymes (EL), and low platelets (LP).

Usually occurs antepartum, between 27 and 37 weeks' gestation. In 15% to 30% of cases, HELLP syndrome is either initially expressed or progresses postpartum.

HELLP syndrome poses significant diagnostic and therapeutic challenges because only 80% to 85% of affected people present typically with hypertension and proteinuria.

It should therefore be considered in any pregnant woman presenting in the second half of pregnancy or immediately postpartum with significant new-onset epigastric/upper abdominal pain until proven otherwise.

Early detection and aggressive management with a combination of intravenous magnesium sulfate, control of blood pressure to prevent or minimize severe systolic hypertension, replacement of blood products, as needed, and timely delivery of the fetus and placenta seem to be the best and safest ways to arrest disease progression and reduce adverse outcomes. Maternal outcomes are improved considerably with this management approach; perinatal outcome depends predominantly on the gestational age at which delivery occurs.

Although delivery is the only treatment that starts recovery, serious manifestations continue into the immediate postpartum period.

Although HELLP syndrome is considered by many to be a severe form of preeclampsia, it has a different definition, characterized by hemolysis (H), elevated liver enzymes (EL), and low platelets (LP) in a pregnant or puerperal woman (usually within 7 days of delivery). The diagnosis and management of preeclampsia is not discussed in detail in this topic. See Preeclampsia.

A woman with HELLP syndrome often displays hypertension (defined as blood pressure ≥140/90 mmHg) and proteinuria (80% to 85%), epigastric/right upper quadrant (RUQ) pain (40% to 90%), nausea and/or vomiting (29% to 84%), headache (33% to 61%), and generalized malaise (90%).[1]Sibai BM, Ramadan MK, Usta I, et al. Maternal morbidity and mortality in 442 pregnancies with hemolysis, elevated liver enzymes and low platelets (HELLP syndrome). Am J Obstet Gynecol. 1993 Oct;169(4):1000-6. http://www.ncbi.nlm.nih.gov/pubmed/8238109?tool=bestpractice.com [2]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 Jun;180(6 Pt 1):1373-84. http://www.ncbi.nlm.nih.gov/pubmed/10368474?tool=bestpractice.com [3]Weinstein L. Syndrome of hemolysis, elevated liver enzymes and low platelet count: a severe consequence of hypertension in pregnancy. Am J Obstet Gynecol. 1982 Jan 15;142(2):159-67. http://www.ncbi.nlm.nih.gov/pubmed/7055180?tool=bestpractice.com [4]Tomsen TR. HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets) presenting as generalized malaise. Am J Obstet Gynecol. 1995 Jun;172(6):1876-8; discussion 1878-80. http://www.ncbi.nlm.nih.gov/pubmed/7778647?tool=bestpractice.com ​​ Some women may present without these signs/symptoms when first evaluated for unexplained thrombocytopenia. The diagnosis of HELLP syndrome should be considered in any pregnant woman presenting in the second half of pregnancy or immediately postpartum with significant new-onset epigastric/RUQ pain until proven otherwise.

Although different classifications have been proposed for HELLP syndrome, the following diagnostic criteria are used: microvascular hemolysis, including characteristic findings (schistocytes, burr cells and polychromasia) on a peripheral blood smear, hematuria, worsening anemia (<8-10 g/dL, depending on the stage of pregnancy and unrelated to blood loss) and/or low serum haptoglobin levels (<25 mg/dL), elevated lactate dehydrogenase (LDH) levels (>600 IU/L), and elevated total serum bilirubin levels (>1.2 mg/dL); elevated liver transaminase levels, including aspartate aminotransferase (AST), and/or alanine aminotransferase (ALT) levels (>70 IU/L or twice the upper limit of normal, not accounted for by alternative diagnoses); and a decreased platelet count (<100x 10⁹/L).[5]American College of Obstetricians and Gynecologists. ACOG practice bulletin no. 222: gestational hypertension and preeclampsia. Jun 2020 [internet publication]. https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2020/06/gestational-hypertension-and-preeclampsia [6]Sibai BM. The HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets): much ado about nothing? Am J Obstet Gynecol. 1990 Feb;162(2):311-6. http://www.ncbi.nlm.nih.gov/pubmed/2309811?tool=bestpractice.com [7]Sibai BM. Diagnosis, controversies, and management of the syndrome of hemolysis, elevated liver enzymes, and low platelet count. Obstet Gynecol. 2004 May;103(5 Pt 1):981-91. http://www.ncbi.nlm.nih.gov/pubmed/15121574?tool=bestpractice.com ​