Johannes Wolf1, Annika Jahnke2, Kai Fechner2, Thomas Richter3, Martin W Laass4, Almuthe Hauer5, Martin Stern6, Jan de Laffolie7, Gunter Flemming8, Thomas Mothes9. 1. Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, Medical Faculty of the University and University Hospital, Leipzig, Germany. 2. EUROIMMUN Medizinische Labordiagnostika AG Lübeck, Germany. 3. Children's Hospital of the Clinical Centre "Sankt Georg" Leipzig, Germany. 4. University Children's Hospital, Technische Universität Dresden, Germany. 5. University Children's Hospital Graz, Austria. 6. University Children's Hospital Tübingen, Germany. 7. Children's Hospital, Justus Liebig University Giessen, Germany. 8. University Children's Hospital Leipzig, Germany. 9. Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, Medical Faculty of the University and University Hospital, Leipzig, Germany. Electronic address: mothes@medizin.uni-leipzig.de.
Abstract
BACKGROUND: Immunofluorescence assays of antibodies against endomysium (EmA) on primate oesophagus sections represent the gold standard in serological testing for coeliac disease (CD). As alternative immunofluorescence technique, staining of primate liver tissue is in use. We compared performance and predictive power of IgA- and IgG-EmA on primate oesophagus and primate liver sections. METHODS: Sera of 298 paediatric biopsy-proven CD patients under gluten-containing diet and 574 disease controls were investigated. Samples were collected between 2004 and 2013 in six children's hospitals. The antibodies were assayed blinded to diagnoses and histological data. Sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) were calculated for different assays. RESULTS: (Oesophagus vs liver): For IgA-EmA, sensitivity (0.953 vs 0.956) and specificity (0.981 vs 0.972) as well as PPV (0.963 vs 0.947) and NPV (0.976 vs 0.979) were comparable on both tissues. IgG-EmA on liver showed significantly higher sensitivity (0.520 vs 0.631; p=0.006) but significantly lower specificity (0.995 vs 0.963; p=0.002) and PPV (0.981 vs 0.899; p=0.0002) than on oesophagus. NPV on liver was higher than NPV on oesophagus, however, the difference was not statistically significant (0.799 vs 0.834; p=0.099). CONCLUSION: Primate liver can be used as alternative, equally well functioning substrate for IgA-EmA testing.
BACKGROUND: Immunofluorescence assays of antibodies against endomysium (EmA) on primate oesophagus sections represent the gold standard in serological testing for coeliac disease (CD). As alternative immunofluorescence technique, staining of primate liver tissue is in use. We compared performance and predictive power of IgA- and IgG-EmA on primate oesophagus and primate liver sections. METHODS: Sera of 298 paediatric biopsy-proven CDpatients under gluten-containing diet and 574 disease controls were investigated. Samples were collected between 2004 and 2013 in six children's hospitals. The antibodies were assayed blinded to diagnoses and histological data. Sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) were calculated for different assays. RESULTS: (Oesophagus vs liver): For IgA-EmA, sensitivity (0.953 vs 0.956) and specificity (0.981 vs 0.972) as well as PPV (0.963 vs 0.947) and NPV (0.976 vs 0.979) were comparable on both tissues. IgG-EmA on liver showed significantly higher sensitivity (0.520 vs 0.631; p=0.006) but significantly lower specificity (0.995 vs 0.963; p=0.002) and PPV (0.981 vs 0.899; p=0.0002) than on oesophagus. NPV on liver was higher than NPV on oesophagus, however, the difference was not statistically significant (0.799 vs 0.834; p=0.099). CONCLUSION: Primate liver can be used as alternative, equally well functioning substrate for IgA-EmA testing.
Authors: Johannes Wolf; Norman Haendel; Johannes Remmler; Carl Elias Kutzner; Thorsten Kaiser; Thomas Mothes Journal: J Clin Lab Anal Date: 2017-11-23 Impact factor: 2.352