Symptoms

 

 

 

 

Pathogenesis

Some theorize that, because HELLP is a severe form of preeclampsia, which, in turn, is defined as gestational hypertension accompanied by proteinuria after the 20th week of gestation.

 

Risk Factors

  • Maternal age older than 34 years
  • Multiparity
  • White race or European descent
  • History of poor pregnancy outcome [115]

 

 

 

 

HELLP is a syndrome characterized by thrombocytopenia, hemolytic anemia, and liver dysfunction believed to result from microvascular endothelial activation and cell injury.

Content 9

 

 

 

There is no known preventive management.

Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.

 

HELLP syndrome is a life-threatening condition that can potentially complicate pregnancy.

Content 13

Content 11

 

HELLP was once known as edema-proteinuria-hypertension gestosis type B in the early 20th century and was later renamed in 1982 by Louis Weinstein.

 

In preeclampsia, defective placental vascular remodeling during weeks 16-22 of pregnancy with the second wave of trophoblastic invasion into the decidua results in inadequate placental perfusion. The hypoxic placenta then releases various placental factors such as soluble vascular endothelial growth factor receptor-1 (sVEGFR-1), which then binds vascular endothelial growth factor (VEGF) and placental growth factor (PGF), causing endothelial cell and placental dysfunction by preventing them from binding endothelial cell receptors. The result is hypertension, proteinuria, and increased platelet activation and aggregation.

Furthermore, activation of the coagulation cascade causes consumption of platelets due to adhesion onto a damaged and activated endothelium, in addition to microangiopathic hemolysis caused by shearing of erythrocytes as they traverse through capillaries laden with platelet-fibrin deposits. Multiorgan microvascular injury and hepatic necrosis causing liver dysfunction contribute to the development of HELLP. [41556789]

Another hypothesis proposes acute maternal immune rejection due to immunocompetent maternal cells coming into contact with a genetically distinct fetus, altering the maternal-fetal immune balance and causing endothelial dysfunction, platelet activation and aggregation, and arterial hypertension. [10]

Other theories include inborn errors of fatty acid oxidative metabolism secondary to long- and medium-chain fatty acid mutations, which cause liver damage secondary to insufficient mitochondrial oxidation of fatty acids required for ketogenesis. [1112]

Yet another theory suggests a placental-instigated acute inflammatory condition targeting the liver. [13]

In addition, dysfunction in the complement system via excessive activation or defective regulation for a given amount of endothelial injury has been proposed to cause damage to hepatic vessels in HELLP. [14]

Many hypotheses attempt to define the pathogenesis of HELLP syndrome, but the true pathology remains a mystery.

USMLE Reviewer (Subscription Required)