Beschreibung:
Technological advances continue to expand the number of genetic disorders that can be diagnosed in utero. Utilization of this new technology has de manded special expertise available in relatively few academic centers. As these new applications have become more widespread so have the realities of the medicolegal implications. Notwithstanding the laboratory challenges, most legal action, at least in the United States, has arisen from the physician's failure to inform a patient about the risks of a genetic disorder or the oppor tunities presented by prenatal diagnosis. Hence an extensive thorough reex amination of the subject seems appropriate and timely. The steady escalation in the number of prenatal genetic studies now being done in the western world makes it imperative for the physician to have a thorough comprehension of the subject in its entirety. I am, therefore, fortu nate in having colleagues who as acknowledged experts have shared their knowledge and experience in order to make this volume a major critical repository of facts and guidance about prenatal genetic diagnosis. The subject matter ranges from a consideration of required genetic counseling through the intricacies of establishing prenatal diagnoses. Special attention is focused on new advances using ultrasound, a-fetoprotein, fetoscopy, and first trimester diagnosis. Both ethical and legal implications are discussed in detail, as is the development of public policy.
1 Genetic Counseling: Prelude to Prenatal Diagnosis.- 1. Introduction.- 2. Guiding Principles in Genetic Counseling.- 2.1. Accurate Diagnosis.- 2.2. Nondirective Counseling.- 2.3. Concern for the Individual.- 2.4. Truth in Counseling.- 2.5. Confidentiality and Trust.- 2.6. Timing of Genetic Counseling.- 2.7. Parental Counseling.- 3. Prerequisites for Genetic Counseling.- 3.1. Knowledge of the Disease.- 3.2. Physician as Counselor.- 3.3. Ability to Communicate.- 3.4. Knowledge of Ancillary Needs.- 3.5. Humanity.- 3.6. Efficacy of Genetic Counseling.- 4. Principles in Practice: Considerations Prior to Amniocentesis and Prenatal Genetic Studies.- 5. Addendum.- 6. References.- 2 Amniocentesis.- 1. Introduction.- 2. Counseling and Consent.- 3. Ultrasound Prior to Amniocentesis.- 4. Amniocentesis Technique.- 5. Timing.- 6. Amniotic Fluid Volume Required.- 7. Risks of Second Trimester Amniocentesis.- 7.1. Fetal Risks.- 7.2. Maternal Risks.- 8. The Newborn Infant and the Child at 1 Year of Age following Amniocentesis.- 9. Addendum.- 10. References.- 3 Amniotic Fluid.- 1. Introduction.- 2. Amniotic Fluid Dynamics.- 2.1. Formation and Circulation.- 2.2. Volume.- 2.3. Origin.- 3. Biochemical and Other Characteristics of Amniotic Fluid.- 3.1. Proteins.- 3.2. Lipids.- 3.3. Enzymes.- 3.4. Disaccharidases.- 3.5. Amino Acids.- 4. Miscellaneous Biochemical Constituents and Other Characteristics of Amniotic Fluid.- 4.1. Creatinine.- 4.2. Blood Group Substances.- 4.3. Antibacterial Activity of Amniotic Fluid.- 5. Addendum.- 6. References.- 4 Amniotic Fluid Cell Culture.- 1. Cell Types.- 2. Cell Viability.- 3. Culture Techniques.- 3.1. Culture Media.- 3.2. Stimulating Cell Growth.- 4. Culture Results.- 5. Problems and Pitfalls.- 5.1. Bloody Samples.- 5.2. Mycoplasma Contamination.- 5.3. Syringe Toxicity.- 5.4. Bacterial or Fungal Contamination.- 5.5. Transport and Storage of Amniotic Fluid Cells.- 6. Karyotyping of Amniotic Fluid Cells without Culturing.- 7. Some Notes on the Establishment of a Prenatal Diagnostic Laboratory.- 8. References.- 5 Prenatal Diagnosis of Chromosomal Disorders.- 1. Introduction.- 2. Frequency of Chromosomal Disorders.- 3. Frequency of Chromosomal Disorders in Fetuses and Live Births.- 4. Worldwide Survey of Prenatal Diagnosis Experience.- 5. Indications for Prenatal Diagnosis of Chromosomal Disorders.- 5.1. Maternal Age.- 5.2. Translocation Carriers.- 5.3. Previous Child with Down Syndrome (Trisomy 21).- 5.4. Advanced Paternal Age.- 5.5. Miscellaneous Indications.- 6. Problems and Pitfalls.- 6.1. Mycoplasma Contamination.- 6.2. Chromosomal Mosaicism.- 6.3. Twins.- 6.4. Polyploidy.- 6.5. Maternal Cell Admixture.- 6.6. Unexpected Abnormal Fetal Karyotype.- 6.7. Chromosomal Polymorphisms.- 6.8. Noncytogenetic Indications for Prenatal Studies.- 6.9. "Unnecessary" Prenatal Studies: Drugs, Chemicals, and Irradiation.- 7. Errors in Prenatal Diagnosis.- 8. Automated Chromosomal Analysis.- 9. Addendum.- 10. References.- 6 Sex Chromosome and X-Linked Disorders.- 1. Introduction.- 2. Prenatal Diagnosis of Sex Chromosome Disorders.- 2.1. Sex Chromosome Disorders in Phenotypic Males.- 2.2. Sex Chromosome Disorders in Phenotypic Females.- 3. Translocations Involving Sex Chromosomes and Autosomes.- 4. Prenatal Diagnosis of X-Linked Disorders.- 5. Fetal Sex Determination.- 5.1. Sex Chromatin Mass (Barr Body).- 5.2. Y-Chromosome Flourescence.- 5.3. Complete Chromosomal Analysis.- 5.4. Amniotic Fluid Testosterone.- 6. Preconception Sex Selection.- 7. Prenatal Diagnosis of Specific X-Linked Disorders.- 7.1. Lesch-Nyhan Syndrome.- 7.2. Fabry Disease.- 7.3. Hunter Syndrome.- 7.4. Glucose-6-phosphate Dehydrogenase Deficiency.- 7.5. Menkes Kinky Hair Disease.- 7.6. X-Linked Ichthyosis.- 8. X-Linked Disorders Potentially Diagnosable in Utero.- 8.1. Adrenoleukodystrophy.- 8.2. The Androgen Resistance Syndromes.- 8.3. Chronic Granulomatous Disease.- 8.4. Combined Immunodeficiency Disease.- 8.5. Duchenne Muscular Dystrophy.- 9. Coagulation D
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