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==Pathophysiology==
==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 vessel]]s. This leads to a [[microangiopathic hemolytic anemia]]: the mesh causes destruction of [[red blood cell]]s as if they were being forced through a strainer. Additionally, [[platelet]]s 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 [[hemorrhage|bleeding]], which can make emergency surgery a serious challenge.
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 vessel]]s. This leads to a [[microangiopathic hemolytic anemia]]: the mesh causes destruction of [[red blood cell]]s as if they were being forced through a strainer. Additionally, [[platelet]]s 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 [[hemorrhage|bleeding]], which can make emergency surgery a serious challenge.
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==Classification==
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The [[platelet]] count has been found to be moderately predictive of the severity of HELLP syndrome. This system is termed the Mississippi classification.
{{cite journal |author=Martin JN, Blake PG, Lowry SL, Perry KG, Files JC, Morrison JC |title=Pregnancy complicated by preeclampsia-eclampsia with the syndrome of hemolysis, elevated liver enzymes, and low platelet count: how rapid is postpartum recovery? |journal=Obstetrics and gynecology |volume=76 |issue=5 Pt 1 |pages=737-41 |year=1990 |pmid=2216215 |doi=}}
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===Class 1===
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Severe:
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===Class 2===
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Moderately severe: Between 50 and 100 K
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===Class 3===
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Mild: > 100 K
==Risk Factors==
==Risk Factors==
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==Differentiating HELLP from other Disorders==
==Differentiating HELLP from other Disorders==
Rarely, post caesarean patient with HELLP may present in shock mimicking either pulmonary embolism or hemorrhage.
Rarely, post caesarean patient with HELLP may present in shock mimicking either pulmonary embolism or hemorrhage.
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==Epidemiology==
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The incidence of HELPP is reported to be 0.2-0.6% of all pregnancies. Of women with (pre)eclampsia, 4-12% also develop signs of a "superimposed" HELLP syndrome. HELLP usually begins during the third trimester, and usually in Caucasian women over the age of 25. Rarely, cases have been reported as early as 23 weeks gestation.
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==Natural History, Complications, Prognosis==
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Mortality is 7-35% and perinatal mortality of the child may be up to 40%.
==Diagnosis==
==Diagnosis==
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*[[Complete blood count]]
*[[Complete blood count]]
−
*[[Liver enzyme]]s
,
[[
renal
function]] and [[electrolyte]]s
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.
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*[[Liver enzyme]]s
−
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*
[[
Renal
function]] and [[electrolyte]]s
−
A positive [[D-dimer]] test in the presence of preeclampsia has recently been reported to be predictive of patients who will develop HELLP syndrome.
{{cite journal |author=Padden MO |title=HELLP syndrome: recognition and perinatal management |journal=American family physician |volume=60 |issue=3 |pages=829–36, 839 |year=1999 |pmid=10498110 |doi=}}
D-dimer is a more sensitive indicator of subclinical coagulpathy and may be a positive before coagulation studies are abnormal.
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*
[[
Coagulation
]] studies.
−
+
*
Often, ''[[fibrin]] degradation products'' (FDPs) are determined, which can be elevated.
−
==Classification==
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*
[[Lactate dehydrogenase]] is a marker of hemolysis and is elevated (>600 U/liter).
−
+
*
[[Proteinuria]] is present but can be mild.
−
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.
{{cite journal |author=Martin JN, Blake PG, Lowry SL, Perry KG, Files JC, Morrison JC |title=Pregnancy complicated by preeclampsia-eclampsia with the syndrome of hemolysis, elevated liver enzymes, and low platelet count: how rapid is postpartum recovery? |journal=Obstetrics and gynecology |volume=76 |issue=5 Pt 1 |pages=737-41 |year=1990 |pmid=2216215 |doi=}}
+
*
A positive [[D-dimer]] test in the presence of preeclampsia has recently been reported to be predictive of patients who will develop HELLP syndrome.
{{cite journal |author=Padden MO |title=HELLP syndrome: recognition and perinatal management |journal=American family physician |volume=60 |issue=3 |pages=829–36, 839 |year=1999 |pmid=10498110 |doi=}}
D-dimer is a more sensitive indicator of subclinical coagulpathy and may be a positive before coagulation studies are abnormal.
==Treatment==
==Treatment==
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The only effective treatment is delivery of the baby. 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, [[corticosteroid]]s and [[antihypertensive]]s ([[labetalol]], [[hydralazine]], [[nifedipine]]) may be sufficient. Intravenous fluids are generally required.
The only effective treatment is delivery of the baby. 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, [[corticosteroid]]s and [[antihypertensive]]s ([[labetalol]], [[hydralazine]], [[nifedipine]]) may be sufficient. Intravenous fluids are generally required.
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−
==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%. HELLP usually begins during the third trimester, and usually in Caucasian women over the age of 25. (Padden, 1999.) Rarely, cases have been reported as early as 23 weeks gestation.
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==See also==
==See also==