The History of Pediatric and Adult Hearing Screening.

OBJECTIVES/HYPOTHESIS: To document the history of hearing seeing in children and adults. STUDY DESIGN: A literature search in all languages was carried out with the terms of hearing screening from the following sources: Pub Med, Science Direct, World Catalog, Index Medicus, Google scholar, Google Books, National Library of Medicine, Welcome historical library and The Library of Congress. METHODS: The primary sources consisting of books, scientific reports, public documents, governmental reports, and other written material were analyzed to document the history of hearing screening. RESULTS: The concept of screening for medical conditions that, when found, could influence some form of the outcome of the malady came about during the end of 19th century. The first applications of screening were to circumscribe populations, schoolchildren, military personnel, and railroad employees. During the first half of the 20th century, screening programs were extended to similar populations and were able to be expanded on the basis of the improved technology of hearing testing. The concept of universal screening was first applied to the inborn errors of metabolism of newborn infants and particularly the assessment of phenylketonuria in 1963 by Guthrie and Susi. A limited use of this technique has been the detection of genes resulting in hearing loss. The use of a form of hearing testing either observational or physiological as a screen for all newborns was first articulated by Larry Fisch in 1957 and by the end of the 20th century newborn infant screening for hearing loss became the standard almost every nation worldwide. CONCLUSIONS: Hearing screening for newborn infants is utilized worldwide, schoolchildren less so and for adults many industrial workers and military service undergo hearing screening, but this is not a general practice for screening the elderly. LEVEL OF EVIDENCE: NA Laryngoscope, 131:S1-S25, 2021.

Protein Substitutes in PKU; Their Historical Evolution.

Protein substitutes developed for phenylketonuria (PKU) are a synthetic source of protein commonly based on L-amino acids. They are essential in the treatment of phenylketonuria (PKU) and other amino acid disorders, allowing the antagonistic amino acid to be removed but with the safe provision of all other amino acids necessary for maintaining normal physiological function. They were first formulated by a chemist and used experimentally on a 2-year-old girl with PKU and their nutritional formulations and design have improved over time. Since 2008, a bioactive macropeptide has been used as a base for protein substitutes in PKU, with potential benefits of improved bone and gut health, nitrogen retention, and blood phenylalanine control. In 2018, animal studies showed that physiomimic technology coating the amino acids with a polymer allows a slow release of amino acids with an improved physiological profile. History has shown that in PKU, the protein substitute's efficacy is determined by its nutritional profile, amino acid composition, dose, timing, distribution, and an adequate energy intake. Protein substitutes are often given little importance, yet their pharmacological actions and clinical benefit are pivotal when managing PKU.

Screening Out Controversy: Human Genetics, Emerging Techniques of Diagnosis, and the Origins of the Social Issues Committee of the American Society of Human Genetics, 1964-1973.

In the years following World War II, and increasingly during the 1960s and 1970s, professional scientific societies developed internal sub-committees to address the social implications of their scientific expertise (Moore, Disrupting Science: Social Movements, American Scientists, and the Politics of the Military, 1945-1975. Princeton: Princeton University Press, 2008). This article explores the early years of one such committee, the American Society of Human Genetics' "Social Issues Committee," founded in 1967. Although the committee's name might suggest it was founded to increase the ASHG's public and policy engagement, exploration of the committee's early years reveals a more complicated reality. Affronted by legislators' recent unwillingness to seek the expert advice of human geneticists before adopting widespread neonatal screening programs for phenylketonuria (PKU), and feeling pressed to establish their relevance in an increasingly resource-scarce funding environment, committee members sought to increase the discipline's expert authority. Painfully aware of controversy over abortion rights and haunted by the taint of the discipline's eugenic past, however, the committee proceeded with great caution. Seeking to harness interest in and assert professional control over emerging techniques of genetic diagnosis, the committee strove to protect the society's image by relegating ethical and policy questions about their use to the individual consciences of member scientists. It was not until 1973, after the committee's modest success in organizing support for a retrospective public health study of PKU screening and following the legalization of abortion on demand, that the committee decided to take a more publicly engaged stance.

Genetics of Phenylketonuria: Then and Now.

More than 950 phenylalanine hydroxylase (PAH) gene variants have been identified in people with phenylketonuria (PKU). These vary in their consequences for the residual level of PAH activity, from having little or no effect to abolishing PAH activity completely. Advances in genotyping technology and the availability of locus-specific and genotype databases have greatly expanded our understanding of the correlations between individual gene variant, residual PAH activity, tetrahydrobiopterin (BH4 ) responsiveness, and the clinical PKU phenotype. Most patients (∼76%) have compound heterozygous PAH gene variants and one mutated allele may markedly influence the activity of the second mutated allele, which in turn may influence either positively or negatively the activity of the biologically active heterotetrameric form of the PAH. While it is possible to predict the level of BH4 responsiveness (∼71%) and PKU severity (∼78%) from the nature of the underlying gene variants, these relationships remain complex and incompletely understood. A greater understanding of these relationships may increase the potential for individualized management of PKU in future. Inherited deficiencies in BH4 metabolism account for about 1%-2% of all hyperphenylalaninemias and are clinically more severe than PKU. Almost 90% of all patients are deficient in 6-pyruvoyl-tetrahydropterin synthase and dihydropteridine reductase.

Fifty years of phenylketonuria newborn screening - A great success for many, but what about the rest?

Guthrie's landmark discovery and the subsequent implementation of the first newborn screening programs for phenylketonuria (PKU) and other inherited errors of metabolism (IEM) could be - in a 50 year retrospective - easily considered among the greatest advances in medicine. They have not just improved the quality of hundreds of thousands of lives, but also transformed our understanding and approach to PKU and IEM in general. However, according to the available albeit very scarce data, many countries and regions seem not to share the benefits of the last 50 years of development. Many of them have not yet introduced the newborn screening for PKU or face significant problems in its implementation. In addition, the issue seems to be underrated by the relevant professional forums. Action to improve the current situation should urgently be taken.

Newborn screening in Spain, with particular reference to Galicia: Echoes of Louis I. Woolf.

After briefly recalling the main events leading to the establishment of newborn screening programmes, this paper details the early history of their introduction in Spain and sketches their expansion to cover the whole Spanish population. Spain is exceptional in that its screening methods have in general been based on planar chromatographic techniques developed or inspired by Louis I. Woolf, rather than on bacterial inhibition tests, as is illustrated by the practice of the newborn screening laboratory of Galicia (N.W. Spain).

Mandatory versus voluntary consent for newborn screening?

Virtually every infant in the United States undergoes a heel stick within the first week of life to test for a variety of metabolic, endocrine, and hematological conditions as part of state-run universal newborn screening (NBS) programs. The history of this mandatory public health program is examined, as well as whether the policy was morally justifiable. Three changes in NBS practice necessitate a re-evaluation of the mandatory nature of NBS. First is the adoption of NBS for hemoglobinopathies in the 1980s that led to the identification of many sickle cell carriers and carriers of other hemoglobin variants. In all other contexts, carrier testing requires consent, and there is no moral rationale why NBS ought to be exceptional. Second is the application of tandem mass spectrometry (MS/MS) to NBS in the 1990s that led to the identification of many metabolic conditions and variants, some of which were not treatable and others of which had unknown clinical relevance. To the extent that the conditions do not need emergent diagnosis and treatment, there is less justification for mandatory screening. Third, there is great interest in using residual blood spots for research, and the cornerstone of research ethics is the voluntary consent of the participant (or his or her proxy). These three changes support revising mandatory NBS with a tiered consent process to best balance respect for parental autonomy and the promotion of children's health.

Pearl S. Buck and phenylketonuria (PKU).

In 1921, Pearl S. Buck gave birth to a daughter, Carol, who became severely retarded and was eventually institutionalized at the Vineland Training School in New Jersey. To help pay for her daughter's care, Buck wrote The Good Earth in 1931, and then other novels and biographies about her life in China, for which she was awarded the Nobel and Pulitzer Prizes, and honored around the world. Years later, she published The Child Who Never Grew, a short piece about her daughter's retardation that also revealed her desperate search for answers and good clinical care. Asbjørn Følling distinguished phenylketonuria (PKU) from other forms of childhood retardation in the mid-1930s, and new assays and biochemical findings eventually led to ways to circumvent the devastating effects of PKU. But for Carol Buck, these advances came too late. It was not until the 1960s that physicians confirmed that her severe retardation was caused by PKU.

The National Institute of Child Health and Human Development and phenylketonuria.

The National Institute of Child Health and Human Development (NICHD) was established shortly after the Guthrie test for screening newborn infants for phenylketonuria (PKU) was introduced. The NICHD supported the study demonstrating the long-term efficacy of screening and a low-phenylalanine diet in preventing mental retardation. With the identification of the adverse impact on fetal development of high intrauterine phenylalanine exposure from a mother with PKU, the NICHD organized and supported the study reported here, demonstrating the protective effect of phenylalanine restriction of the mother's diet during pregnancy. The study provides clear guidance for the management of pregnancy in women with PKU.

Research design, organization, and sample characteristics of the Maternal PKU Collaborative Study.

OBJECTIVE: The Maternal PKU Collaborative Study (MPKUCS) was initiated in 1984 by the National Institute of Child Health and Human Development (NICHD). The purpose was to assess the efficacy of dietary restriction of phenylalanine in reducing morbidity in offspring of women with hyperphenylalaninemia (HPA). A contract was awarded to Childrens Hospital Los Angeles as the Coordinating Center to provide implementation of the research protocol, data collection, and analysis. METHODS: The Study included four regional contributing centers: Childrens Hospital Los Angeles (Western Region), Boston Children's Hospital (Northeast Region), University of Illinois (Midwest Region), and University of Texas Medical Branch, Galveston (Southeast Region). Within each region, many participating clinics were responsible for obstetric care, treatment, and monitoring protocols. In 1985, Canada joined the MPKUCS, and in 1992, Germany entered. They were selected because they provided dietary supplies and strong professional services. Acquisition began in 1984 and ended in October 1995. The study included 574 pregnancies in women with HPA and 100 control subjects matched on age, race, parity, and weeks of gestation. The sample included women with blood phenylalanine values >240 micromol/L, 66% of whom had classical PKU, 22% had atypical PKU, and 12% had mild HPA. Informed consents were obtained on all participants. The women ranged in age from 15 to 36 years of age, with a mean age at conception of 23 years. Teenage pregnancies accounted for 19%. Seventy-five percent graduated from high school. Offspring included 416 newborns, 317 of whom were evaluated at 4 years of age and 289 at 6 to 7 years. Follow-up involved medical, nutritional, psychosocial, and psychological assessments. CONCLUSION: Women with PKU treated before conception and in control of their blood phenylalanine levels between 120 and 360 micromol/L (2-6 mg) exhibited normal pregnancies and neonatal outcome. Surprisingly, women who achieved control in the recommended range by 8 weeks of pregnancy also had a normal fetal outcome.