Related Experiment Videos
Studies in meconium. An approach to screening tests to detect cystic fibrosis
Insights
Newborn screening for cystic fibrosis (CF) can be improved. Adding lactase and beta-D-fucosidase assays to the existing Boehringer-Mannheim test significantly reduces false positives in CF screening.
Area of Science:
- Biochemistry
- Pediatrics
- Genetics
Background:
- Newborn screening for cystic fibrosis (CF) is crucial for early intervention.
- Current screening methods, like the Boehringer-Mannheim (BM) test, can produce false-positive results.
- Improving the accuracy and reliability of CF screening tests is an ongoing challenge.
Purpose of the Study:
- To evaluate the efficacy of adding lactase and beta-D-fucosidase assays to the BM test for newborn CF screening.
- To determine if these enzyme assays can reduce false-positive rates in CF screening.
- To assess the performance of lactase and beta-D-fucosidase assays as standalone or complementary diagnostic tools.
Main Methods:
- A mass screening program involving 20,182 meconium specimens was conducted.
- The Boehringer-Mannheim (BM) strip test was used initially to detect albumin.
- Lactase and beta-D-fucosidase assays were proposed as additional diagnostic markers for CF in meconium.
Main Results:
- The BM test identified 46 positive results out of 20,182 specimens.
- Twenty-nine infants had confirmed CF, while 17 yielded false-positive results with the BM test.
- Incorporating lactase and beta-D-fucosidase assays could have excluded 11 of the 17 false positives, reducing false-positive rates by approximately 61%.
Conclusions:
- The addition of lactase and beta-D-fucosidase assays to the BM test can significantly enhance the specificity of newborn screening for cystic fibrosis.
- These enzyme assays demonstrate potential for improving diagnostic accuracy and reducing unnecessary follow-up procedures associated with false-positive screening results.
- Further validation of these enzyme assays may lead to more reliable and cost-effective CF screening protocols.
Abstract:
Screening for cystic fibrosis (CF) in newborns is desirable, and efforts should continue in establishing a system of easily available, reliable, simple, and inexpensive tests. In addition to the Boehringer-Mannheim (BM) test for the detection of albumin, we propose the assay for lactase and beta-D-fucosidase in meconium. These latter two enzymes are present in the meconium of babies with CF and absent in meconium of most healthy babies. In a mass screening program for CF involving 20,182 specimens of meconium using only the BM strip, we found 46 positive results. Twenty-nine specimens came from infants with CF, six of whom had meconium ileus. Seventeen specimens yielded false-positive results by the BM test. Eleven of these would have been excluded by the addition of the lactase and beta-D-fucoside assay, thus reducing the false-positive test results by nearly 61%. In a comparative study of the three methods, the lactase and beta-D-fucosidase yielded 1.2% false-positives when examined independently. Performance of these two assays may allow greater specificity in diagnosis when used in addition to the BM test.