Biomaterial Database

Newborn screening in Japan: restructuring for the new era. 2008

Seiji Yamaguchi

Department of Pediatrics, Shimane University School of Medicine, 89-1 En-ya-cho, Izumo, Shimane 693-8501, Japan. seijiyam@med.shimane-u.ac.jp

Nationwide neonatal mass screening for inherited metabolic diseases has started in Japan since 1977. At least 8000 children have probably been spared from handicaps resulting from such diseases over the past 30 years. Recently remarkable changes have been made to the evolving neonatal screening system. Declining birth rate and economic problems in Japan have demanded a more effective neonatal screening system. Development of new innovative screening methods and treatment tools, e.g. tandem mass spectrometry (MS/MS) technology and enzyme replacement therapy for mucopolysaccharidosis (MPS), have facilitated expansion of target diseases in neonatal screening. We have carried out pilot screening using MS/MS in 6 laboratories in Japan. The incidence of inherited metabolic diseases was found to be 1 in 9330 (65 cases out of 606,380 babies screened) during the period between 1997 and 2007. The incidence was lower than those of Europe or USA (about 1 in 4000 to 5000). The disease frequency between unscreened symptomatic cases and asymptomatic cases detected through MS/MS screening were also found to be different. In MS/MS screening, the most common organic acidemia was propionic acidemia, whereas in symptomatic cases, methylmalonic acidemia was the most common. Further study of ethnic diversity in severity of propionic academia is required. The outcomes of patients detected in the MS/MS screening were significantly favourable. The results showed the benefits of MS/ MS screening. The diagnostic support network for gas chromatography-mass spectrometry (GC/ MS) analysis and enzyme determination has also been developed. We have developed an automated system of GC/MS data processing and auto-diagnosis which allowed the GC/MS data processing to be extremely fast and simple. Enzyme evaluation for diagnostic support for screening, including a method using peripheral blood and high performance liquid chromatography (HPLC), and another method of in-vitro probe assay using cultured cells and MS/MS. Furthermore, re-location of screening laboratories for a more efficient screening network will be required such that at least 30,000 samples can be analysed in each laboratory.

UI	MeSH Term	Description	Entries
D007231	Infant, Newborn	An infant during the first 28 days after birth.	Neonate,Newborns,Infants, Newborn,Neonates,Newborn,Newborn Infant,Newborn Infants
D007564	Japan	A country in eastern Asia, island chain between the North Pacific Ocean and the Sea of Japan, east of the Korean Peninsula. The capital is Tokyo.	Bonin Islands
D008661	Metabolism, Inborn Errors	Errors in metabolic processes resulting from inborn genetic mutations that are inherited or acquired in utero.	Inborn Errors of Metabolism,Metabolism Errors, Inborn,Error, Inborn Metabolism,Errors Metabolism, Inborn,Errors Metabolisms, Inborn,Errors, Inborn Metabolism,Inborn Errors Metabolism,Inborn Errors Metabolisms,Inborn Metabolism Error,Inborn Metabolism Errors,Metabolism Error, Inborn,Metabolism Inborn Error,Metabolism Inborn Errors,Metabolisms, Inborn Errors
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D015997	Neonatal Screening	The identification of selected parameters in newborn infants by various tests, examinations, or other procedures. Screening may be performed by clinical or laboratory measures. A screening test is designed to sort out healthy neonates (INFANT, NEWBORN) from those not well, but the screening test is not intended as a diagnostic device, rather instead as epidemiologic.	Infant, Newborn, Screening,Newborn Infant Screening,Newborn Screening,Neonatal Screenings,Newborn Infant Screenings,Newborn Screenings,Screening, Neonatal,Screening, Newborn,Screening, Newborn Infant,Screenings, Neonatal,Screenings, Newborn,Screenings, Newborn Infant
D053719	Tandem Mass Spectrometry	A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.	Mass Spectrometry-Mass Spectrometry,Mass Spectrometry Mass Spectrometry,Mass Spectrometry, Tandem