Social implications of algorithmic management in cases of cystic hygroma.

Cystic hygroma is a congenital abnormality linked to lymphatic malformations. Should lymphatic vessels fail to connect and drain, they may result in a large, multilocal cyst. Cystic hygromas are most commonly found on the neck, but can also be found in other areas. With advanced diagnostic technologies, clinicians are better able to diagnose cystic hygroma. (1)

In this issue of the Journal, Forrester and Merz (2) present a descriptive epidemiology of cystic hygroma. They call attention to factors associated with the occurrence of cystic hygroma. They also note that prenatal detection of a cystic hygroma and the detection of chromosomal abnormalities significantly increase the likelihood that a pregnancy will be voluntarily terminated.

Prospective parents may be concerned about whether their children are likely to have birth defects. Prenatal diagnosis can lessen this uncertainty. Test results, however, raise additional concerns about what to do when a fetus is found to have a congenital or chromosomal abnormality.

Since there are apparent linkages between cystic hygroma and special challenges in birth outcomes, many physicians recommend the termination of these pregnancies. In their comprehensive review, Deschamps et al (1) constructed an algorithm for the management of prenatally diagnosed cystic hygroma. Whenever cystic hygroma is diagnosed in conjunction with a morphologic or chromosomal variant, their algorithm concludes in a terminated pregnancy. If, however, there is a persistent hygroma without one of these variants, they recommend consultation with the parents about continuation.

This algorithmic reasoning is not unusual. "Abnormal" karyotypes are associated with much higher rates of induced abortion than are "normal" karyotypes. (3) Moreover, the late detection of "abnormal" karyotypes is the most common reason for third-trimester termination of a pregnancy. (4) The current study's findings reflect this trend. Although this algorithm is presented as a descriptive model, it has become prescriptive. That is, the model reflects a directive form of genetic counseling wherein fetuses with chromosomal abnormalities should not be continued. Such algorithms reduce the agency of both physician and prospective parent.

Because the algorithm is prescriptive, physicians need not consider the possibility for differential expression of genotypes when providing genetic counseling. In cases of cystic hygroma, reliance on the simple existence of chromosomal variants to control the decision--rather than consultation between parent and physician--is particularly significant. For fetuses with a cystic hygroma, both "abnormal" and "normal" chromosomal patterns are associated with physical and mental developmental challenges within the prescriptive algorithm. (5) A genotype in itself, however, determines neither the severity nor the course of a genetically-linked condition. Environmental and chance variables have a substantial influence.

For their part, prospective parents need not consider that induced abortion is a choice, as the option of raising a child who has potentially significant challenges is foreclosed altogether in the prescriptive model. On the other hand, when the algorithm is not followed, ie, when there is nondirective genetic counseling, there is a much lower rate of pregnancy termination for fetuses with chromosomal variants. (6) Although raising a child with potentially severe challenges is not appropriate for all parents, a directive algorithm demanding abortion is equally inappropriate. Nondirective genetic counseling would restore agency to both physician and prospective parent by allowing case-by-case consultation, and giving actual choice to the prospective parent.

An additional concern stemming from algorithmic management of cystic hygroma is its authorization of negative eugenics. Classical eugenics is based on breeding for desired characteristics. By contrast, negative eugenics eliminates "unfit" offspring. When a fetus is aborted because it has an "abnormal" karyotype, the termination of pregnancy contributes to the practice of negative eugenics. (7) In addition to this practice, algorithms that rely on karyotyping normalize negative eugenics by removing the possibility of questioning the algorithm's outcome. Given that the public has a substantial concern that genetic technology will lead to eugenics and genocide, (8,9) physicians should avoid medical praxis that confirms these fears. For this reason, physicians may want to avoid algorithms and, again, provide nondirective genetic counseling.

Physicians and prospective parents in consultation may decide that induced abortion is the best option. Other consultations may result in a continued pregnancy. Both outcomes are justifiable. Cystic hygroma, in itself, can complicate a pregnancy. Physical, mental, and developmental disabilities associated with cystic hygromas can add additional parenting burdens. If, however, the challenges of cystic hygroma and associated chromosomal and morphologic variants are used to reduce the agency of medical interlocutors and to promote the practice of negative eugenics, physicians and patients both must consider the long-term social effects of algorithmic case management alongside the immediate medical advantages.

Anyone who stops learning is old, whether at twenty or eighty. Anyone
who keeps learning stays young. The greatest thing in life is to keep
your mind young.
--Henry Ford

Accepted December 16, 2003.

Copyright [c] 2004 by The Southern Medical Association

0038-4348/04/9707-0622

Please see "Descriptive Epidemiology of Cystic Hygroma: Hawaii, 1986 to 1999" on page 631 of this issue.

References

1. Deschamps P, Jourdain O, Paillett C, et al. Etiology, prognosis and management of nuchal cystic hygroma: 25 new cases and literature review. Eur J Obstet Gynecol Reprod Biol 1996;71:3-10.

2. Forrester MB and Merz RD. Descriptive epidemiology of cystic hygroma, Hawaii, 1986-1999. South Med J 2004;97:631-636.

3. Baena N, Guitart M, Ferreres JC, et al. Fetal and placental chromosome constitution in 237 pregnancy losses. Ann Genet 2001;44:83-88.

4. Dommergues M, Benachi A, Benifla JL, et al. The reasons for termination of pregnancy in the third trimester. Br J Obstet Gynaecol 1999;106:297-303.

5. Baumann C, Delagarde R, Vuillard E, et al. Etude de l'issue des grossesses et du devenir des enfants nes apres un diagnostic de pathologie de la nuque a l'echographie du 1er ou 2e trimester. J Gynecol Obstet Biol Reprod (Paris) 2001;30:S68-S74.

6. Merschede D, Louwen F, Nippert I, et al. Lower rates of pregnancy termination for prenatlly diagnosed Klinefelter syndrome and other sex chromosome polysomies. Am J Med Genet 1998;80:330-334.

7. Sheldon S, Wilkinson S. Termination of pregnancy for reason of foetal disability: are there grounds for a special exception in law? Med Law Rev 2001;9:85-109.

8. Condit CM, Templeton A, Bates BR, et al. An exploration of attitudinal barriers to delivery of race-targeted pharmacogenomics among informed lay persons. Genet Med 2003;5:385-392.

9. Bates BR, Poirot K, Harris TM, et al. Evaluating direct-to-consumer marketing of race-based pharmacogenomics: A focus group study of public understandings of applied genomic medication. J Health Communication 2004; in press.

From the School of Communication Studies, Ohio University, Athens, OH.

Reprint requests to Benjamin R. Bates, School of Communication Studies, Ohio University, Lasher Hall, Athens, Ohio 45701. Email: [e-mail]