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Fetal exsanguination by chorionic villus sampling
THE LANCET
is limited from only hours to a m a x i m u m of a few weeks, t we believe that aggressive life-sustaining treatment should be regarded as artificial prolongation of death. T h u s , it is not the doctor's decision that limits the baby's life---as the m o t h e r in this case s u p p o s e d - - b u t the extreme congenital handicaps. T h e m o t h e r believed that only G o d decides about life a n d death, on the other h a n d , she believed in the use o f all technical facilities against a hopeless situation: are n o t these contradictory beliefs? One could argue that with these fatal inborn failures the death of the child was obviously allowed by God, who could have worked a miracle, as the m o t h e r believed he would, before intensive care or after the death of the anencephalic baby. Veatch's arguments (director at the K e n n e d y Institute o f Ethics, Georgetown University) are even more doubtful because he does not differentiate between "to make a baby dead" and to let h i m die without intensive care, which means with comfort care including hydration, sufficient nutrition, and temperature support. T h i s superficial view could easily be misused by supporters of euthanasia and lead to the other extreme. Christian congregations agree on the main point o f this discussion: one is in no way obliged to use disproportionate therapeutic means (earlier called " e x t r a o r d i n a r y " means) under all circumstances. 2,s We believe that this District Court judgment is more than questionable because, misusing the right of free exercise of religion, it puts nurses and doctors in a moral conflict: in every-day conditions babies with a chance o f survival who need intensive care m u s t often be transferred to other hospitals because of lack of beds; at the same time, should aggressive life-sustaining therapy for an anencephalic baby be an obligation?
Ludwlg-Christoph Ddczy, Rudolf Trawdger, Ahmet Gedik Department of Paediatrics, University of Innsbruck, A-6020 Innsbruek, Austria
1 Peabody JL, Emery JR, Ashwal S. Experience with anencephalic infants as prospective organ donors. N EnglJ Med 1989; 321: 344--50. 2 The General Synod of the Church of England, Board for Social Responsibility. Severely abnormal babies: morally legitimate "not to seek to preserve life". London: Church Information Office, 1982. 3 Flannery A. Vatican Council II, more post conciliar documents: declaration on euthanasia. New York: Costello Publishing, 1982; 2: 510-17.
Fetal exsanguinatlon by chorlonlc villus sampling SIR--It is known that transabdominal chorionic villus sampling ( T A C V S ) can cause feto-maternal transfusions ( F M T s ) that have, remarkably, not been associated with fetal death by exsanguination, x,2 We observed a case o f fetal death following T A C V S with immediate post-procedural persisting fetal bmdycardia (71 beats/rain), absent doppler-flow in the umbilical cord, a n d a raised maternal serum-alpha-fetoprotein ( M S A F P ) of 678 k U / L . Before sampling, there was a n o r m a l fetal heart-rate (179 beats/min), normal umbilical corddoppler-flow, and normal M S A F P (8 kU/L). T A C V S was done at 12 weeks because of advanced maternal age (36). 15 m g chorionic villi was obtained, and a normal 46,XY karyotype found. At this gestation the difference between a post-sampling and pre-sampling M S A F P of 670 k U / L represents an F M T o f 1' 1 m L being 35% to 40% offeto-placental blood-volume. One week after T A C V S fetal death was diagnosed. Fetal death by exsanguination due to a massive T A C V S related F M T has not been documented. Animal experiments, show that fetuses survive a haemorrhage up to 2 1 % of feto-placental blood-volume. 3 Since in h u m a n fetuses similar or even larger F M T - v o l u m e s have been established without apparent effect on pregnancy outcome, 1,z one may w o n d e r whether the F M T at the same time is compensated by a
Vo1342 • December 18/25, 1993
materno-fetal transfusion ( M F T ) . However, massive F M T s and M F T s should arouse suspicion of possible immunological sequelae, especially in multiparous women, who might have been sensitised in a previous pregnancy.
Froas J Los, Milena GJ Jahoda, Juriy W Wladimiroff, Christoph Brezinka Departments of Clinical Genetics and Obstetrics and Gynaecology, University Hospital Dijkzigt, Erasmus University, 3000 Rotterdam, Netherlands
Adriana M Hagenaars Department of Teratology, Endocrinology and Perinatal Screening, National Institute of Public HeaRh and £nvironmentat Protection, 8ilthoven, Netherlancts
1 Los FJ, Pijpers L, Jahoda M G J , et al. Transabdominal chorionic villus sampling in the second trimester of pregnancy: feto-matemal transfusions in relation to pregnancy outcome. Prenat Diagn 1989; 9:
521-26. 2 Smidt-Jensen S, Lundsteen C, Lind AM, Dinesen K, Philip J. Transabdominal chorionic villus sampling in the second and third trimester of pregnancy: chromosome quality, reporting time, and feto-maternal bleeding. Prenat Diagn 1993j 13: 957-69. 3 Brace RA. Fetal blood volume responses to acute fetal haemorrhage. Circ Res 1983; 52: 730--34.
Genetic techniques and surveillance of tuberculosis SIR--Genewein and colleagues (Oct 2, p 841) report the u s e o f genetic techniques in tuberculosis surveillance. A n understanding of infectious disease transmission may benefit from advances in molecular biology. As these workers s h o w convincingly and elegantly, such techniques m a y enable identification of different strains to ascertain their relation in a population. However, there is one worrying aspect to this enthusiastic adoption of genetic t e c h n i q u e s - - a tendency to assume either that social information about transmission dynamics is no longer relevant or that it can be read from genetic codes. Genewein and co-workers say that they u s e d D N A fingerprinting as a systematic tool for identifying interstrain relations and transmission within a d e f i n e d population. In their report and D r u c k e r ' s accompanying commentary (p 817), this tool is seen to be far more powerful than routine public health surveillance; for example, Drucker states, " . . . the details and dynamics of a community subepidemic of tuberculosis can be identified in ways completely beyond the ken o f routine surveillance a n d contact tracing". T o support these claims, it is i m p o r t a n t to consider further the molecular technology a n d the relation between sociological and microbiological data on transmission. T h e usefulness of D N A fingerprinting will d e p e n d on the reliability and reproducibility of the techniques a n d their ability to discriminate. F o r example, in any chain o f transmission, are all isolates identical at the molecular level? I f not, what degree o f difference is important? 1 T h e most effective way to address such questions is to combine microbiological with social research. T h e relevant social information will be crucial, for example, to definitions of concordance a n d discordance within a population, and of strain variation over time. A c o m b i n e d social a n d microbiological research p r o g r a m m e might also mitigate against the temptation to generalise from partial networks. I t should be appreciated that Genewein et al obtained detailed data only for the social networks of people whose isolates showed identical restriction fragment-length p o l y m o r p h i s m ( R F L P ) patterns. Clearly, these social data m a d e interpretation o f the genetic techniques possible e v e n t h o u g h neither G e n e w e i n n o r D r u c k e r emphasis this social research. F r o m a research perspective, it should be emphasised that the same information was not available o n those with 1559
is limited from only hours to a m a x i m u m of a few weeks, t we believe that aggressive life-sustaining treatment should be regarded as artificial prolongation of death. T h u s , it is not the doctor's decision that limits the baby's life---as the m o t h e r in this case s u p p o s e d - - b u t the extreme congenital handicaps. T h e m o t h e r believed that only G o d decides about life a n d death, on the other h a n d , she believed in the use o f all technical facilities against a hopeless situation: are n o t these contradictory beliefs? One could argue that with these fatal inborn failures the death of the child was obviously allowed by God, who could have worked a miracle, as the m o t h e r believed he would, before intensive care or after the death of the anencephalic baby. Veatch's arguments (director at the K e n n e d y Institute o f Ethics, Georgetown University) are even more doubtful because he does not differentiate between "to make a baby dead" and to let h i m die without intensive care, which means with comfort care including hydration, sufficient nutrition, and temperature support. T h i s superficial view could easily be misused by supporters of euthanasia and lead to the other extreme. Christian congregations agree on the main point o f this discussion: one is in no way obliged to use disproportionate therapeutic means (earlier called " e x t r a o r d i n a r y " means) under all circumstances. 2,s We believe that this District Court judgment is more than questionable because, misusing the right of free exercise of religion, it puts nurses and doctors in a moral conflict: in every-day conditions babies with a chance o f survival who need intensive care m u s t often be transferred to other hospitals because of lack of beds; at the same time, should aggressive life-sustaining therapy for an anencephalic baby be an obligation?
Ludwlg-Christoph Ddczy, Rudolf Trawdger, Ahmet Gedik Department of Paediatrics, University of Innsbruck, A-6020 Innsbruek, Austria
1 Peabody JL, Emery JR, Ashwal S. Experience with anencephalic infants as prospective organ donors. N EnglJ Med 1989; 321: 344--50. 2 The General Synod of the Church of England, Board for Social Responsibility. Severely abnormal babies: morally legitimate "not to seek to preserve life". London: Church Information Office, 1982. 3 Flannery A. Vatican Council II, more post conciliar documents: declaration on euthanasia. New York: Costello Publishing, 1982; 2: 510-17.
Fetal exsanguinatlon by chorlonlc villus sampling SIR--It is known that transabdominal chorionic villus sampling ( T A C V S ) can cause feto-maternal transfusions ( F M T s ) that have, remarkably, not been associated with fetal death by exsanguination, x,2 We observed a case o f fetal death following T A C V S with immediate post-procedural persisting fetal bmdycardia (71 beats/rain), absent doppler-flow in the umbilical cord, a n d a raised maternal serum-alpha-fetoprotein ( M S A F P ) of 678 k U / L . Before sampling, there was a n o r m a l fetal heart-rate (179 beats/min), normal umbilical corddoppler-flow, and normal M S A F P (8 kU/L). T A C V S was done at 12 weeks because of advanced maternal age (36). 15 m g chorionic villi was obtained, and a normal 46,XY karyotype found. At this gestation the difference between a post-sampling and pre-sampling M S A F P of 670 k U / L represents an F M T o f 1' 1 m L being 35% to 40% offeto-placental blood-volume. One week after T A C V S fetal death was diagnosed. Fetal death by exsanguination due to a massive T A C V S related F M T has not been documented. Animal experiments, show that fetuses survive a haemorrhage up to 2 1 % of feto-placental blood-volume. 3 Since in h u m a n fetuses similar or even larger F M T - v o l u m e s have been established without apparent effect on pregnancy outcome, 1,z one may w o n d e r whether the F M T at the same time is compensated by a
Vo1342 • December 18/25, 1993
materno-fetal transfusion ( M F T ) . However, massive F M T s and M F T s should arouse suspicion of possible immunological sequelae, especially in multiparous women, who might have been sensitised in a previous pregnancy.
Froas J Los, Milena GJ Jahoda, Juriy W Wladimiroff, Christoph Brezinka Departments of Clinical Genetics and Obstetrics and Gynaecology, University Hospital Dijkzigt, Erasmus University, 3000 Rotterdam, Netherlands
Adriana M Hagenaars Department of Teratology, Endocrinology and Perinatal Screening, National Institute of Public HeaRh and £nvironmentat Protection, 8ilthoven, Netherlancts
1 Los FJ, Pijpers L, Jahoda M G J , et al. Transabdominal chorionic villus sampling in the second trimester of pregnancy: feto-matemal transfusions in relation to pregnancy outcome. Prenat Diagn 1989; 9:
521-26. 2 Smidt-Jensen S, Lundsteen C, Lind AM, Dinesen K, Philip J. Transabdominal chorionic villus sampling in the second and third trimester of pregnancy: chromosome quality, reporting time, and feto-maternal bleeding. Prenat Diagn 1993j 13: 957-69. 3 Brace RA. Fetal blood volume responses to acute fetal haemorrhage. Circ Res 1983; 52: 730--34.
Genetic techniques and surveillance of tuberculosis SIR--Genewein and colleagues (Oct 2, p 841) report the u s e o f genetic techniques in tuberculosis surveillance. A n understanding of infectious disease transmission may benefit from advances in molecular biology. As these workers s h o w convincingly and elegantly, such techniques m a y enable identification of different strains to ascertain their relation in a population. However, there is one worrying aspect to this enthusiastic adoption of genetic t e c h n i q u e s - - a tendency to assume either that social information about transmission dynamics is no longer relevant or that it can be read from genetic codes. Genewein and co-workers say that they u s e d D N A fingerprinting as a systematic tool for identifying interstrain relations and transmission within a d e f i n e d population. In their report and D r u c k e r ' s accompanying commentary (p 817), this tool is seen to be far more powerful than routine public health surveillance; for example, Drucker states, " . . . the details and dynamics of a community subepidemic of tuberculosis can be identified in ways completely beyond the ken o f routine surveillance a n d contact tracing". T o support these claims, it is i m p o r t a n t to consider further the molecular technology a n d the relation between sociological and microbiological data on transmission. T h e usefulness of D N A fingerprinting will d e p e n d on the reliability and reproducibility of the techniques a n d their ability to discriminate. F o r example, in any chain o f transmission, are all isolates identical at the molecular level? I f not, what degree o f difference is important? 1 T h e most effective way to address such questions is to combine microbiological with social research. T h e relevant social information will be crucial, for example, to definitions of concordance a n d discordance within a population, and of strain variation over time. A c o m b i n e d social a n d microbiological research p r o g r a m m e might also mitigate against the temptation to generalise from partial networks. I t should be appreciated that Genewein et al obtained detailed data only for the social networks of people whose isolates showed identical restriction fragment-length p o l y m o r p h i s m ( R F L P ) patterns. Clearly, these social data m a d e interpretation o f the genetic techniques possible e v e n t h o u g h neither G e n e w e i n n o r D r u c k e r emphasis this social research. F r o m a research perspective, it should be emphasised that the same information was not available o n those with 1559