HELLP syndrome is a life-threatening complication of pre-eclampsia. Both conditions occur during the latter stages of pregnancy, or sometimes after childbirth.
HELLP is an abbreviation of the main findings:
Signs and symptoms
Often, a patient who develops HELLP syndrome has already been followed up for
pregnancy-induced hypertension (
gestational hypertension), or is suspected to develop
pre-eclampsia (high blood pressure and
proteinuria). Up to 8% of all cases present
after delivery.
There is gradual but marked onset of headaches (30%), blurred vision, malaise (90%), nausea/vomiting (30%), "band pain" around the upper abdomen (65%) and tingling in the extremities. Oedema may occur but its absence does not exclude HELLP syndrome. Arterial hypertension is a diagnostic requirement, but may be mild. Rupture of the liver capsule and a resultant hematoma may occur. If the patient gets a seizure or coma, the condition has progressed into full-blown eclampsia.
Diagnosis
In a patient with possible HELLP syndrome, a batch of
blood tests is performed: a
full blood count,
liver enzymes,
renal function and
electrolytes and
coagulation studies. Often,
fibrin degradation products (FDPs) are determined, which can be elevated.
Lactate dehydrogenase is a marker of hemolysis and is elevated (>600 U/liter).
Proteinuria is present but can be mild.
Classification
The
platelet count has been found to be moderately predictive of severity: under 50 million/L is class I (severe), between 50 and 100 is class II (moderately severe) and >100 is class III (mild). This system is termed the Mississippi classification (Martin
et al 1990).
Pathophysiology
The exact cause of HELLP is unknown, but general activation of the coagulation cascade is considered the main underlying problem. Fibrin forms crosslinked networks in the small
blood vessels. This leads to a
microangiopathic hemolytic anemia: the mesh causes destruction of
red blood cells as if they were being forced through a strainer. Additionally,
platelets are consumed. As the
liver appears to be the main site of this process, downstream liver cells suffer
ischemia, leading to periportal necrosis. Other organs can be similarly affected. HELLP syndrome leads to a variant form of
disseminated intravascular coagulation (DIC), leading to paradoxical
bleeding, which can make emergency surgery a serious challenge.
Treatment
The only effective treatment is delivery of the baby, preferably by
cesarean section. Several medications have been investigated for the treatment of HELLP syndrome, but evidence is conflicting as to whether
magnesium sulfate decreases the risk of seizures and progress to eclampsia. The DIC is treated with
fresh frozen plasma to replenish the coagulation proteins, and the
anemia may require
blood transfusion. In mild cases,
corticosteroids and
antihypertensives (
labetalol,
hydralazine,
nifedipine) may be sufficient. Intravenous fluids are generally required.
Epidemiology
Its incidence is reported as 0.2-0.6% of all pregnancies. Of women with (pre)eclampsia, 4-12% also develop signs of a "superimposed" HELLP syndrome. Mortality is 7-35% and perinatal mortality of the child may be up to 40%.
History
HELLP syndrome was identified as a distinct clinical entity (as opposed to severe preeclampsia) by Dr Louis Weinstein in 1982.
References
- Martin JN Jr, Blake PG, Lowry SL, Perry KG Jr, Files JC, Morrison JC. Pregnancy complicated by preeclampsia-eclampsia with the syndrome of hemolysis, elevated liver enzymes, and low platelet count: how rapid is postpartum recovery? Obstet Gynecol 1990;76:737-41. PMID 2216215.
- Weinstein L. Syndrome of hemolysis, elevated liver enzymes, and low platelet count: a severe consequence of hypertension in pregnancy. Am J Obstet Gynecol 1982;142:159-67. PMID 7055180.
Obstetrics | Medical emergencies | Syndromes
HELLP-Syndrom | HELLP syndrome | HELLP症候群 | HELLP-syndroom