Segal, who worked at Children's Hospital of Philadelphia for 41 years, was international-ly recognized for his contributions to the scientific understanding of inherited metabolic diseases. He was a particular expert in galactosemia, in which children are born without an enzyme necessary for processing milk sugar. If untreated, it can cause brain damage, organ failure and death.
As ombudsman for Penn's General Clinical Research Center, he advocated for patients' rights and also oversaw informed consent for people participating as subjects in research studies.
Segal established a metabolic diagnostic laboratory at Children's Hospital that has become an important resource for physicians and a world center of research into many inborn metabolic diseases. During his career at the hospital, he received some $20 million dollars in research funding from the National Institutes of Health and other sources and published more than 400 papers.
Born in Camden, N.J., Segal graduated from Camden High School. He earned a bachelor's degree from Princeton University and his medical degree from Harvard Medical School. After completing postgraduate training at New York Hospital-Cornell Medical Center and the Hospital of the University of Pennsylvania, he served as a senior investigator for the NIH's National Institute of Arthritis and Metabolic Diseases from 1958 to 1965.
In 1966, Segal came to Children's Hospital here as a senior physician and became a professor of pediatrics at the University of Pennsylvania School of Medicine. At Children's Hospital, he established the Division of Biochemical Development and Molecular Diseases, and launched a metabolic diagnostic laboratory that became one of the premier facilities in the United States for the detection of rare metabolic conditions. He introduced sophisticated diagnostic technologies such as mass spectrometry and nuclear magnetic resonance into the laboratory.
Among his many honors, Segal earned the Children's Hospital of Los Angeles Award for Unique Contributions to Galactosemia Research, several Ethel Brown Foerderer Awards for Excellence and the Robert H. Herman Memorial Award from the American Society for Nutrition.
He is survived by his wife of 51 years, Joan Segal; sons Mark Segal and Roy Segal; a sister, Dorothy Segal; and one grandson.