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California Newborn Screening Program

Follow-up of Initial Positive Tests

Because of the urgency of the need for treatment, all initial positive test results for PKU, galactosemia and primary congenital hypothyroidism are immediately reported by telephone by the area Newborn and Prenatal Screening (NAPS) laboratory to an assigned ASC NBS Coordinator. These coordinators are located throughout the state in the seven regions and are linked to the NBS Program central computer in Richmond. The State Genetic Disease Laboratory (GDL) reviews and releases the hemoglobin results. Potentially clinically significant hemoglobinopathies and other initial positive results are reported on a daily "Interesting Case Report" to the Centers. An ASC NBS Coordinator from the respective Center immediately telephones the newborn's physician to provide interpretation of the test and explain necessary follow-up. Medical consultants are available to provide additional information and consultation when necessary.

Reference Ranges (PDF)

For tests not within normal limits, a second blood sample called a "recall specimen" is collected. The recall specimens for phenylketonuria and hypothyroidism (borderline values only) are sent to the State Genetic Disease Laboratory for testing. Recall specimens for galactosemia are sent to the State-funded galactosemia confirmatory laboratory at Children’s Hospital; Los Angeles, while those for hemoglobin disorders are sent to the hemoglobin reference laboratory at Children’s Hospital Oakland.

The primary care physician is responsible for notifying the family about the test results and for obtaining a recall specimen. The physician may request assistance from the ASC NBS Coordinator in this matter. Parents are also notified of the initial positive test result by letter from the Coordinator. Enclosed with the letter is a pamphlet that explains the meaning of an initial positive screening result and the need for recall testing. A copy of the letter and the pamphlet are also sent to the newborn’s physician. The Coordinator tracks all initial positive cases to ensure that appropriate follow-up occurs.

When a physician is not available, or fails to obtain a recall specimen, the Coordinator contacts the family directly to help make the necessary follow-up arrangements. The Coordinators can locate most families; however, assistance is occasionally requested of the local health department in the follow-up of an infant. Locating and informing parents may be an urgent matter since the risk of irreversible damage to affected infants is significant. All local health officers are responsible for making every effort to obtain newborn screening specimens when requested by the Genetic Disease Screening Program or an ASC. Public health nurses may be called on to assist with obtaining initial specimens for out-of-hospital births and for repeat testing for inadequate and initial positive results [CCR 17, Section 6507.1 (b)].

The ASC NBS Coordinator notifies the newborn's physician of the recall test results. Because primary care physicians are often unfamiliar with these rare disorders, the Coordinator will assist the provider in referring a family to a California Children's Services (CCS)-Approved Metabolic, Endocrine or Sickle Cell Disease Center for specialized diagnosis and treatment. The comprehensive team approach to care offered at the Centers is particularly important in treatment of these disorders. Should a primary care provider wish to speak with a specialist prior to referral to a CCS Center, the Newborn Screening Coordinator can make arrangements for consultation with the appropriate medical consultant.

The Newborn Screening Program is what the name implies – it screens for certain specified disorders detectable at birth. Primary care providers should not be relying solely on the screening results. If symptoms develop for a baby who had a negative newborn screen, the primary care provider needs to follow up on those clinical signs.

Follow-up of Inadequate Results

The Newborn Screening Program follows up on all newborns who have an inadequate newborn screening specimen. A second specimen is collected and sent to the Newborn and Prenatal Screening Laboratory (NAPS) for testing. The Area Service Center (ASC) follows the case until adequate and normal screening results are reported and the case is closed out and removed from the ASC’s daily report.

1. Initial follow-up on inadequate tests:

  • The NAPS laboratory calls the appropriate ASC when the sample is inadequate.
  • The ASC, in turn, calls the newborn’s physician (or the hospital neonatal intensive care unit [NICU], if the infant is still hospitalized) to arrange for a repeat specimen to be obtained. A follow-up letter is sent to the physician and a Confirmation of Contact (C of C) is data-entered into the State computer.
  • The health facility where the initial specimen was obtained (or another facility more convenient to the family) is notified about the returning newborn and the repeat test that is needed.

2. The ASC Newborn Screening Coordinator will follow a case until it is resolved. This occurs when:

  • An adequate repeat specimen on an inadequate is obtained and matched to the inadequate specimen.
  • A previously collected adequate specimen is matched to the inadequate specimen.
  • The case is closed due to infant death, noncompliance, or whereabouts unknown.

Follow-up of Confirmed Positive Results

The Area Service Center (ASC) NBS Coordinator notifies the newborn’s physician of the recall test results. For confirmed positive results, the Coordinator will provide information on the confirmatory test and explain the recommended follow-up. Medical consultants are available at each ASC to provide additional information and consultation when necessary. Coordinators can also assist the provider in referring a family to a California Children’s Services (CCS) approved Metabolic, Endocrine or Sickle Cell Disease Center for specialized diagnosis and treatment.

Parents play an active role in close monitoring of these conditions and in treatment regimens consisting of special diets and/or daily medication.   For children with sickle cell disease, it is critical that parents be skilled in identifying early warning signs of health problems that require prompt medical attention. Educational materials developed by the Program and distributed through health care providers provide practical information and support to parents. Upon request to the NBS Program, educational materials are available at no cost to health care providers, hospitals, clinics and local health departments.

The Program has now been in operation since October 30, 1980, with screening for sickle cell disease and related hemoglobin disorders starting on February 27, 1990. A pilot program for identification of Hb H disease was added in 1996 and became officially part of the NBS Program in 1999. As of August 1998, the Program has screened 9,120,141 births and has detected 2,883 cases of primary congenital hypothyroidism, 334 cases of classical PKU, and 122 cases of galactosemia. In addition, 996 cases of sickle cell disease and 166 cases of other clinically significant hemoglobinopathies were detected.

The Program has been very successful due in part to the active involvement of primary care providers in the follow-up of inadequate and positive test results. The Area Service Center staff and medical consultants provide assistance to the primary care provider. All infants with non-negative results are tracked to ensure confirmation of diagnosis and initiation of treatment. However, a small number of newborns do fall through the cracks despite all the checks and balances of the program. Approximately 1,000 babies (0.5% of the births) are not screened at birth, another 125 with inadequate results of the initial test never receive a second test, and a very small number of infants with an initial positive test results are lost to follow-up. Therefore, it is critical that pediatric care providers review the newborn screening results on every infant under their care. If a child is under one year of age and has no record of the NBS test in the chart, a request should be made to the ASC NBS Coordinator for a copy of the results mailer. If there is no record of screening, a specimen should be collected and submitted to the Program for testing. The Coordinator can assist in this process.

Limitations of Screening


Last modified on: 4/26/2011 2:59 PM