autoimmune disease Glutenintolerance
Conditions
Interventions
Phase 1 (Development and Validation of HLA- DQ2/8 typing using RT-PCR in DNA
isolated from dried blood spots obtained from one droplet of blood) From 50
children attending the LUMC dept. of Pediatri
Sponsors
Leids Universitair Medisch Centrum
Eligibility
Age
No minimum to 17 Years
Inclusion criteria
Inclusion criteria: Phase 1: - age 1-18 years, - suspicion of gluten-related disease, - parents have a sufficient knowledge of Dutch language, - written informed consent from child and/or parent Phase 2: - age 12 months to 4 years, - not diagnosed with CD, - not on a GFD, - parents have a sufficient knowledge of Dutch language, - written informed consent from the parent(s)
Exclusion criteria
Exclusion criteria: - no informed consent, - insufficient knowledge of Dutch language and/or inability to understand the information provided, - bleeding disorders.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Main study parameter/endpoint Phase 1: • Accuracy of the test for HLA-DQ typing. The results of the HLA-DQ2 and DQ8-typing using the dried blood spots will be compared with the results of the traditional HLA-typing. DNA extraction for HLA-DQ typing from dry blood spots will be performed using the QIAamp method [11-14]. A protocol to isolate DNA has been developed and the isolation is executable by all the well skilled laboratory analysts. DNA extraction per sample takes about 15 minutes and it is possible to determine several samples at the same time. The equipment and optical technology are already present at the LUMC. The usage of RT-PCR on DNA acquired from dried blood samples was successful in another setting and can easily be applied to HLA-DQ2/DQ8 typing [10]. The fast, accurate and simple RT-PCR-based assay for the genotyping and homozygosity analysis of the CD-related HLA alleles has been validated [15, 16]. The assay overcomes the major limitations of protocols currently in use, allowing HLA-DQ2/DQ8 genotyping by using only three real-time PCR reactions. For the appraisal of DQ2 homozygosity, only one more reaction is needed. These reactions are easily automated, and the running time is exactly short which make it suitable for large screening or case-finding studies in diagnostic procedures, as it is demonstrated by their successful application in our HLA diagnostic laboratory. This approach has proven its effectiveness to diagnostic HLA-typing in CD suspicion in a North-Eastern Spanish population, confirming that the HLA-DQ genotyping is a powerful tool for stratifying CD risk. This has been confirmed in other cohorts [15-18]. The validation will be done at the LUMC, department of Pediatrics. Since no previous studies have been done on the validation of the HLA-DQ2/8- typing in dried blood spots, the aim of this part of the study is to validate the test in dried spots collected in the hospital setting. From 50 children attendin | — |
Secondary
| Measure | Time frame |
|---|---|
| Secondary study parameters/endpoints Cost-effectiveness of the investigational strategy To evaluate the cost-effectiveness of case finding with and without HLA-DQ2/8 typing. This part of the study will be done by the health economist. Factors that will be included are cost for: the novel genetic test, health care professionals at the YHCC and laboratorial, storage and transport of the material for the genetic test. These costs will compared to the costs in the situation without HLA-DQ2/8 testing as done in GLUTENSCREEN. Time investment by medical and nursing staff at the YHCCs (sec) Costs of the investigational strategy (time, materials) (¤) | — |
Countries
Netherlands
Outcome results
None listed