CHAPTER 5: NEWBORN SCREENING

LEARNING OBJECTIVES

INTRODUCTION

Newborn screening (NBS) is a public health activity aimed at the early identification of infants affected with conditions for which timely intervention leads to the elimination or reduction of mortality and morbidity associated with these conditions. Universal NBS started in the early 1960s, thanks to the pioneering work of Dr. Robert Guthrie, who developed the first screening test for phenylketonuria using dried blood spots on filter paper. Thanks to the use of filter paper as a collection device, universal NBS for over 30 inherited conditions is now possible world-wide, saving the lives and intellect of hundreds of children every year.

NEWBORN SCREENING

NBS is not just a clinical test, but rather a program that includes several components: laboratory testing, follow-up activities, clinical care, education, and quality assurance. The smooth integration of all components of the program determines the effectiveness of NBS. There are guidelines to assist NBS programs in establishing protocols and procedures dealing with each of the components. These guidelines have been published by the Clinical and Laboratory Standards Institute and include guidelines on blood collection on filter paper (NBS01-A6), testing methodology (NBS04-A, NBS05-A, NBS06-A), follow-up activities (NBS02-A2), sample collection, and follow-up of premature/sick babies (NBS03-A). These documents are available at www.clsi.org. In addition to these guidelines, follow-up algorithms and basic clinical information on the diseases screened have been developed by the American College of Medical Genetics and Genomics (ACMGG) and they are available at http://www.ncbi.nlm.nih.gov/books/NBK55827/.

With new information on the natural history of inherited disorders and new discoveries leading to novel therapies, the number of conditions that could potentially be screened for in the newborn period is dramatically increasing. However, there are specific criteria to be met before a condition is considered for inclusion in a NBS program. These criteria have been developed and applied by the Uniform Panel Work Group convened by the American College of Medical Genetics and Genomics (ACMG), which, at the beginning of the 2000s, was given the task of identifying conditions to be included in NBS programs in the United States. The final report of the work group can be found at http://mchb.hrsa.gov/programs/newbornscreening/screeningreportpdf.pdf and it outlines the evaluation process. Conditions were evaluated in three different categories: a) clinical characteristics of the disease (incidence, natural history, burden of the disease); b) analytical characteristics of the test (availability, reliability, sensitivity, specificity, cost); and c) follow-up, diagnosis, treatment, and management of the disease (availability, acceptability, efficacy, cost of treatment).

As a result of the work of the Uniform Panel Work Group, a list of 29 conditions meeting all criteria set forth by the workgroup was published^1...