The Renal Lesions of Toxaemia and Abruptio Placentae Studied by Light and Electron Microscopy

Abstract

Summary Renal biopsy in the early puerperium was carried out on 20 patients with toxaemia and 13 abruptio placentae without preceding toxaemia. The tissue obtained was studied by light and electron microscopy. All patients had a very similar glomerular lesion with (1) swelling and slight proliferation of the endotheliat cells, (2) increase in the number of mesangial cells and the amount of the mesangial matrix, and (3) granular deposits derived from fibrinogen within the endothelial cells and the mesangial matrix. It is suggested that in both toxaemia and abruptio placentae there is release of thromboplastin from the placental site into the circulation which causes disseminated intravascular coagulation; this process is complicated by the fact than in pregnancy the fibrinolytic mechanism is in any case impaired. The glomerular lesion in both groups is the result of the response of the endothelial cells and mesangium to deposited fibrin or its derivatives.

A Renal Biopsy Study in Toxaemia of Pregnancy

“…Thomson et al (1972) found similar lesions in both toxaemia and abruptio placentae and suggested that the glomerular lesion in these two groups of patients was the result of the response of the endothelial cells and mesangium to deposited fibrin or its derivatives. This hypothesis was supported by early workers using immunofluorescent techniques, which detected fibrin within endothelial and mesangial cells and along the capillary walls (Vassalli et al, 1963;Morris et al, 1964).…”

“…Especial attention was paid to the deposition of fibrin since earlier authors (Vassalli et al, 1963;Thomson et al, 1972) had reported large amounts of fibrin or fibrinogen derivatives in the glomeruli of pre-eclamptic patients. In marked contrast to the findings of these workers, only small amounts of fibrin were detected in 7 of our 11 biopsy specimens.…”

Intrarenal Vascular Lesions Associated with Pre-Eclampsia

“…Electron-microscopic examination of cor tical tissue reveals vacuolation, droplet for mation, cytoplasmic strands and an increase in particulate structure in the endothelial and mesangial cells of the glomerular tuft [9][10][11][12], Vacuolation of the cytoplasm, trabeculae and foot processes of the epithelial cells is also a common finding [5,18] and although limited fusion of foot processes can be observed, this is rarely extensive so that in general the capillary basement membrane is not thickened. Oc casional patchy thickening of the basement membrane has however been reported in severe cases of pre-eclampsia [5], Electrondense material almost certainly fibrin or one of its derivatives is frequently observed on the endothelial surface of the basement membrane and fibrin has also been noted both between and within the endothelial cells [8][9][10][11][12]21].…”

Transport Kinetics of Alpha-Aminoisobutyric Acid and Water in Pre-Eclamptic Pregnancies: An in vitro Study

“…In the present investigation, fetal and maternal flow rates were maintained in the physiological range, but this ideal situation may not be present in pregnancies complicated by PEES. Several investigators have reported placental and villous abnormalities in preeclamptic pregnancies (such as thickened basement membrane and fibrin deposits) [20,22]. Abnormalities such as increased vascular resistance [25,26], augmented vascular reactivity to angiotensin II and noradrenaline [27,28] and decreased plasma volume [29] have also been reported.…”

“…The lower AIB transport observed in pre-eclamptic pregnancies may be attributed to the thickened basal membrane and other vascular and villous abnormalities reported in this condition [20][21][22]. Interestingly, a study conducted by our research group has demonstrated alteration of the Na + -H + exchanger mechanism in pre-eclamptic placentae [23], and the present results of altered AIB transport kinetics seem to imply that the Na + -H + exchanger plays an impor- Nandakumaran/Omu/Diejomaoh Al-Yatama/Harouny/Sugathan tant role in the transport of A-type amino acids.…”