When a woman reaches 32 weeks into a first pregnancy, it’s possible that a peculiar syndrome may occur—possibly due to loss of a genetic imprinting in placental tissues (1)—that appears to originate from an implantation abnormality (1). The abnormality causes ischemia in placental blood vessels and could potentially cause a placental infarct, but usually triggers vasoconstrictors to activate fluid retention that causes hypertension (1).
The ischemic placenta also disrupts endothelia causing a predisposition to disseminated intravascular coagulation (1). This blocks microcirculation causing tissue hypoxia and reduced blood flow in the kidney causes albuminuria, which leads to systemic edema (1). The symptoms may be accompanied by headache and vision disruption (2). In addition, the woman may have memory and concentration problems, according to a study published in March (3).
Also, a March-published “revised view” in Placenta also reviews placental stress as leading to the syndrome (4). The study suggests a two-stage model claiming, “it is not only an endothelial disease, but a disorder of systemic inflammation” (4).
The syndrome was previously called toxemia, but wasn’t a good name since no toxins are involved (1). The syndrome is now called preeclampsia referring to late occurrence of convulsions and coma (1). But it could use another name more in line with its symptoms for early detection… Post-32-HyperPsychoProteinuria. And it could be separated into Stage 1 and 2.
Reference List
1. Yu L, Chen M, Zhao D et al. The H19 Gene Imprinting in Normal Pregnancy and Pre-eclampsia. Placenta 2009.
2. Nowak TJ, Handford AG. Pathophysiology: Concepts and Applications for Health Professionals. New York: McGraw-Hill, 2004.
3. Baecke M, Spaanderman ME, van der Werf SP. Cognitive function after pre-eclampsia: an explorative study. J Psychosom Obstet Gynaecol 2009;30:58-64.
4. Redman CW, Sargent IL. Placental stress and pre-eclampsia: a revised view. Placenta 2009;30 Suppl A:S38-S42.
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