Amniotic fluid gamma-glutamyl transferase for prediction of biliary atresia in cases of non-visualisation of the fetal gallbladder: a retrospective study using a validated analytical platform and local reference range
Publication in refereed journal
CUHK Authors
Full Text
View Full-text in CUHK Digital Object Identifier (DOI) DOI for CUHK Users |
Altmetrics Information
.
Other information
AbstractIntroduction: The level of amniotic fluid gamma-glutamyl transferase (AFGGT) may help identify biliary atresia (BA) in cases of non-visualisation of the fetal gallbladder (NVFGB). This study aimed to validate a serum/plasma matrix–based gamma-glutamyl transferase (GGT) assay for amniotic fluid (AF) samples, establish a local gestational age–specific AFGGT reference range, and evaluate the efficacy of AFGGT for predicting fetal BA in pregnancies with NVFGB using the constructed reference range.
Methods: The analytical performance of a serum/ plasma matrix–based GGT assay on AF samples was evaluated using a Cobas c502 analyser. Amniotic fluid gamma-glutamyl transferase levels in confirmed euploid singleton pregnancies (16+0 to 22+6 weeks of gestation) were determined using the same analyser to establish a local gestational age–specific reference range (the 2.5th to 97.5th percentiles). This local reference range was used to determine the positive predictive value (PPV) and negative predictive value (NPV) of AFGGT level <2.5th percentile for identifying fetal BA in euploid pregnancies with NVFGB.
Results: The serum/plasma matrix–based GGT assay was able to reliably and accurately determine GGT levels in AF samples. Using the constructed local gestational age–specific AFGGT reference range, the NPV and PPV of AFGGT level <2.5th percentile for predicting fetal BA in pregnancies with NVFGB were 100% and 25% (95% confidence interval=0, 53), respectively.
Conclusion: In pregnancies with NVFGB, AFGGT level ≥2.5th percentile likely excludes fetal BA. Although AFGGT level <2.5th percentile is not diagnostic of fetal BA, fetuses with AFGGT below this level should be referred for early postnatal investigation.
Methods: The analytical performance of a serum/ plasma matrix–based GGT assay on AF samples was evaluated using a Cobas c502 analyser. Amniotic fluid gamma-glutamyl transferase levels in confirmed euploid singleton pregnancies (16+0 to 22+6 weeks of gestation) were determined using the same analyser to establish a local gestational age–specific reference range (the 2.5th to 97.5th percentiles). This local reference range was used to determine the positive predictive value (PPV) and negative predictive value (NPV) of AFGGT level <2.5th percentile for identifying fetal BA in euploid pregnancies with NVFGB.
Results: The serum/plasma matrix–based GGT assay was able to reliably and accurately determine GGT levels in AF samples. Using the constructed local gestational age–specific AFGGT reference range, the NPV and PPV of AFGGT level <2.5th percentile for predicting fetal BA in pregnancies with NVFGB were 100% and 25% (95% confidence interval=0, 53), respectively.
Conclusion: In pregnancies with NVFGB, AFGGT level ≥2.5th percentile likely excludes fetal BA. Although AFGGT level <2.5th percentile is not diagnostic of fetal BA, fetuses with AFGGT below this level should be referred for early postnatal investigation.
Acceptance Date06/02/2023
All Author(s) ListCHEUNG Tommy Yee Ting, WONG Natalie Kwun Long, SAHOTA Daljit Singh, SUBRAMANIAM Shreenidhi Ranganatha, LAU So Ling, ZHU Xiaofan, LUI Wai Ting, CHAN Edwin Kin Wai, KWOK Yvonne Ka Yin, CHOY Kwong Wai, LEUNG Tak Yeung, CHAN Michael Ho Ming, WONG Felix Chi Kin, TING Yuen Ha
Journal nameHong Kong Medical Journal
Year2024
Month6
Volume Number30
Issue Number3
Pages218 - 226
ISSN1024-2708
eISSN2226-8707
LanguagesEnglish-United Kingdom