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
paresthesia (tingling in the extremities).
Edema 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.
Disseminated intravascular coagulation is also seen in about 20% of all women with HELLP syndrome,
[2] and in 84% when HELLP is complicated by
acute renal failure.
[3]
Patients who present symptoms of HELLP can be misdiagnosed in the early stages, increasing the risk of liver failure and morbidity.
[4] Rarely, post caesarean patient may present in shock condition mimicking either pulmonary embolism or reactionary haemorrhage.
[edit] 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.
A positive
D-dimer test in the presence of preeclampsia has recently been reported to be predictive of patients who will develop HELLP syndrome.
[5] D-dimer is a more sensitive indicator of subclinical coagulopathy and may be positive before coagulation studies are abnormal.[
citation needed]
[edit] Classification
The
platelet count has been found to be moderately predictive of severity: under 50,000/mm3 is class I (severe), between 50,000 and 100,000 is class II (moderately severe) and >100,000 is class III (mild). This system is termed the Mississippi classification.
[6]
[edit] 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.