The primary purpose of neonatal screening for hemoglobinopathies is to identify infants with sickle cell disease, for whom early diagnosis, parental education, prophylactic penicillin, and comprehensive medical care markedly reduce morbidity and mortality.
In 1987, an NIH consensus development panel concluded that "the benefits of screening (for sickle cell disease) are so compelling that universal screening should be provided. State law should mandate the availability of these services while permitting parental refusal." During the subsequent 10 years, the number of states that conduct newborn screening for hemoglobinopathies has increased dramatically. Currently, 43 states and the District of Columbia screen newborns for sickle cell disease. In the Mountain States Region, 4 of 6 states (Arizona, Colorado, New Mexico, and Wyoming) screen all newborns for sickle cell disease.
Each of the laboratory methods currently used to screen newborns for sickle cell disease (hemoglobin electrophoresis, isoelectric focusing, and high performance liquid chromatography) also detects infants who are heterozygous carriers for a wide variety of hemoglobin variants, including hemoglobins S (sickle cell trait), C, and E. In most instances, identification of a hemoglobinopathy carrier has no implications whatsoever for the health or medical care of the infant. Geneticists and ethicists generally agree that population screening for genetic disorders should be voluntary, preceded by informed consent, and strictly confidential.
While newborn screening programs strive to protect the confidentiality of results, few are voluntary (many are mandated by state law), and meaningful informed consent is rarely obtained. Thus, the detection of hemoglobinopathy carriers by neonatal screening, an unavoidable byproduct of screening for sickle cell disease, presents newborn screening programs with a significant dilemma. How and under what circumstances should the information be conveyed to the infant's parents, many of whom were not aware that newborn screening might yield such genetic information, and at least some of whom might not have consented to such testing had it been voluntary?
There are a number of potential benefits to providing families with information, education, and counseling regarding the identification of an infant who is a hemoglobinopathy carrier. These include the education of families so that they will be more knowledgeable about hemoglobin variants (and not confuse benign carrier states with disease), the avoidance of redundant testing in the future, and the opportunity to offer testing of parents and other family members (and thus identify and counsel couples with sickle cell trait who are at risk for having future children with sickle cell disease).
Many feel that a decision not to provide test results and offer education and counseling to such parents would be unethical and/or would place screening programs in legal jeopardy. In at least one instance, legal action (for wrongful birth) was pursued (and an out-of-court settlement achieved) by parents who were not notified that their child had sickle cell trait and who subsequently conceived a child with sickle cell disease.
The potential harm of identifying hemoglobinopathy carriers has also been articulated. Risks include the exposure of mistaken paternity and confusion between sickle cell trait and disease with consequent stigmatization, anxiety, and inappropriate parenting. Documentation that such harm may occur was provided over 20 years ago by a sickle cell screening program for older children in Seattle. Families were informed about the test results by a clinic pediatrician, yet 72% of parents erroneously anticipated significant symptoms in their child with sickle cell trait, and 49% inappropriately imposed some restriction of physical activity.
The potential for similar problems is a real concern for those responsible for newborn screening programs. Discrimination by employers and/or health insurance organizations against carriers of serious genetic disorders is another potential risk of identifying hemoglobinopathy carriers.
Logistically, the provision of appropriate education and counseling services to families of hemoglobinopathy carriers identified by newborn screening is a formidable and potentially costly task. Approximately 50 infants who are carriers for hemoglobin variants are identified for each individual with sickle cell disease. Thus, thousands of carrier infants are identified each year by neonatal screening programs in the United States.
In many states, the large number of such cases far exceeds the capacity of clinical genetics programs and genetic counselors. Many states have long-standing contracts with community-based sickle cell organizations or with academic sickle cell centers to provide follow-up services. Frequently, but not always, education and counseling are provided by health care professionals (nurses, social workers, etc.) who have extensive knowledge of and experience with hemoglobinopathies. To help ensure the highest quality for the services, many have advocated that a national program be established to set minimum standards of education and training for hemoglobinopathy educators/counselors and to provide for a certification process.
A compromise between not reporting any carrier test results and attempting to notify, educate, and counsel all families with a carrier infant was briefly entertained in Oregon. The idea was to routinely report and follow up only results indicative of clinically significant disease. An attempt would be made to inform parents of all infants that the newborn screening test might have revealed information about a genetic carrier state. Interested parents could then request the results and receive education and counseling. Parents who did not request results would not be informed of a child's carrier status. This plan for "informed request" was never implemented for a number of practical, legal, ethical, and political reasons.
In September 1995, a national symposium was held to address the legal, ethical, technical and logistical issues concerning the follow-up of hemoglobinopathy carriers identified through neonatal screening. Participants included representatives from newborn screening programs and sickle cell organizations, geneticists, ethicists, hematologists, and consumers. There was a clear consensus that families of hemoglobinopathy carriers should be notified of the results and that appropriate education and counseling should be available. As a direct outgrowth of that conference, the CORN Sickle Cell, Thalassemia and Other Hemoglobin Variants Committee (with advice and support from the CORN Newborn Screening Committee) developed guidelines for the follow up of hemoglobinopathy carriers detected by newborn screening.
These guidelines (available through the Mountain States Regional Genetic Services Network coordinator) were recently endorsed by the Steering Committee of CORN and are summarized below:
Ideally, education about newborn screening, which usually includes testing for sickle cell disease, should be provided to families during prenatal care - well in advance of the time of delivery.A mechanism should be in place in State Newborn Screening Programs so that all results of sickle cell newborn screening can be made available to parents of all infants who are tested.
Parents of all infants who are detected to be carriers of hemoglobin variants should be offered appropriate education, counseling and testing. Individuals who counsel should have appropriate training and credentialing in order to insure the highest quality of services for families of carriers detected by newborn screening.
Newborn screening programs should have a mechanism for monitoring and assessing the approaches to, responses to, and costs of providing carrier education and counseling services.
Meanwhile, the Sickle Cell Disease Association of America has initiated the lengthy process of developing a national certification program for hemoglobinopathy counselors.
