HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Reduction of false negative results in screening of newborns for homocystinuria.

AbstractBACKGROUND:
Mental retardation and other disabilities (including ectopia lentis, osteoporosis, and thromboembolism) in patients who have homocystinuria as a result of a deficiency of cystathionine beta-synthase can be prevented by the screening of newborns with measurement of blood methionine, followed by the early treatment of affected infants. Many infants with this disorder, however, are not identified by screening and have irreversible brain damage.
METHODS:
We reviewed the results of neonatal screening for homocystinuria over a period of 32 years in New England. Additional specimens were requested for repeated analysis when blood methionine measurements were at or above the established cutoff level. Homocystinuria due to cystathionine beta-synthase deficiency was confirmed by quantitative amino acid analyses.
RESULTS:
For the first 23.5 years of the review period, the blood methionine cutoff value was 2 mg per deciliter (134 micromol per liter). Among the 2.2 million infants screened during that period, 8 with homocystinuria were identified (1:275,000). In 1990, the cutoff value was reduced to 1 mg per deciliter (67 micromol per liter). Among the 1.1 million infants screened in the subsequent 8.5 years, 7 with the disorder were identified (1:157,000). During the latter period, the specimens were collected from six of the seven infants when they were two days of age or less; five of the six had blood methionine concentrations below 2 mg per deciliter. Use of the reduced cutoff level increased the false positive rate from 0.006 percent to 0.03 percent.
CONCLUSIONS:
A cutoff level for blood methionine of 1 mg per deciliter in neonatal screening tests for homocystinuria should identify affected infants who have only slightly elevated concentrations of methionine and reduce the frequency of false negative results.
AuthorsM J Peterschmitt, J R Simmons, H L Levy
JournalThe New England journal of medicine (N Engl J Med) Vol. 341 Issue 21 Pg. 1572-6 (Nov 18 1999) ISSN: 0028-4793 [Print] United States
PMID10564686 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • Methionine
Topics
  • False Negative Reactions
  • Homocystinuria (blood, diagnosis, epidemiology)
  • Humans
  • Infant, Newborn
  • Methionine (blood, metabolism)
  • Neonatal Screening (standards)
  • New England (epidemiology)
  • Reference Values
  • Sensitivity and Specificity

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: