We wish to raise serious ethical issues concerning the article Glomerular endotheliosis in normal pregnancy and pre-eclampsia by Strevens et al. published in the September issue.

The authors performed renal biopsies on 36 women with hypertension in pregnancy and 12 healthy pregnant volunteers. The study was approved by the University of Lund Ethics committee. ‘All participants were informed of the risk of complications such as renal haematoma or haematuria and agreed to receive blood transfusion if this should prove necessary’. There is no evidence that participants were told that their kidney might need embolisation for persistent bleeding (1:500). One patient required blood transfusion for a significant biopsy-related haematoma that took two months to resolve. Published data suggest a risk of bleeding to be of the order of 9%, to be higher in those with a lower haematocrit (as would be expected in the pregnant group) and for a 1-g haemoglobin decrease in many patients1. Other serious risks include mortality2, arteriovenous fistulas2 and surgery including nephrectomy (1:1000). Automated biopsy devices reduced complication rates when strict protocols were adhered to, namely, exclusion of all patients with BP > 140/90 mmHg or platelets lower than normal3. These latter conditions were not met in the 36 index patients.

Even if the participants understood these risks, we do not accept that it was ethical to ask them to participate. The authors justify renal biopsy in controls to establish whether glomerular endotheliosis is pathognomonic for pre-eclampsia and state that if not, it would be unethical to use renal biopsy for diagnostic purposes. But renal biopsy is never used for the diagnosis of pre-eclampsia in modern clinical practice because the information derived from biopsy will not alter management sufficiently to justify the risk. The only indications for renal biopsy in pregnancy are for the diagnosis of intrinsic renal disease such as renal failure, nephrotic syndrome and transplant rejection, and then only if remote from term.

The chairman of our local Research Ethics Committee felt such studies should not be approved. If renal biopsies are not usually done to diagnose pre-eclampsia, it is not ethical to do so for research purposes. The scientific need for controls does not make it ethical to biopsy healthy pregnant women, the risks of biopsy being too great. Indeed, in the relatively rare situations where normal renal tissue is needed for research, it is almost always taken from healthy regions of nephrectomy specimens.

Renal biopsy is very rarely performed in pregnancy and most obstetricians have little experience of the procedure or its risks. Therefore, what efforts did the editors make to obtain appropriate opinions concerning the ethics and risks of these studies before manuscript acceptance? In publishing this, the Journal appears to condone renal biopsy for research purposes. We contend that this study is clearly unethical. If the editors thought publication justifiable for special reasons, they should have insisted on the authors discussing these reasons.


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  2. References
  • 1
    Marwah DS, Korbet SM. Timing of complications in percutaneous renal biopsy: what is the optimal period of observation? Am J Kidney Dis 1996;111: 4752.
  • 2
    Preda A, Van Dijk LC, Van Oostaijen JA, et al. Complication rate and diagnostic yield of 515 consecutive ultrasound-guided biopsies of renal allografts and native kidneys using a 14-guage Biopty gun. Eur Radiol 2003;13527530.
  • 3
    Hergesell O, Felten H, Andrassy K, et al. Safety of USS guided percutaneous renal biopsy—retrospective analysis of 1090 consecutive cases. Nephrol Dial Transplant 1998;13: 975977.