All for a few drops of blood ...

A tiny heel prick has saved the lives of thousands of babies in North Carolina.

The state's infant screening program, which began in the 1960s to search for the metabolic disorder PKU, now identifies more than 30genetic and metabolic disorders, catching an annual average of 230 potentially fatal or life-altering problems before they escalate.

"With PKU, a lot of patients wound up in institutions and were cared for by the state," said Leslie Wolf, director of the State Laboratory of Public Health in Raleigh, which runs the screening program. When the amino acid disorder is identified early and treatment is provided, Wolf said, "children can lead close to a normal life." That's the case for many metabolic disorders, which are generally rare, but treatable if they're caught early.

Expanding the program to screen for more disorders became feasible in the 1990s, using mass spectrometry technology and a process developed by David Millington, a Duke University scientist. Millington adapted the technology to break down blood samples into chemical fragments, enabling scientists to flag abnormalities.

Now most states routinely screen for dozens of disorders, following recommendations from the March of Dimes.

In April, North Carolina added a screening for cystic fibrosis, a rare genetic disease that affects the lungs and other organs. Eighteen cases of cystic fibrosis have been identified in the first six months of screening, state data show.

Sickle cell syndromes and hypothyroidism are the most commonly discovered disorders in North Carolina.