Dry Blood Spot Screening Test for Neonatal Cholestasis Patients

Aims: 1. Developed a screening test for neonatal cholestasis using dry blood spot 2. Improve patient survival by early diagnosis of treatable neonatal cholestasis disease such as biliary atresia and inborn error of bile acid metabolism. Phase I - Validation of method for quantification of disease markers on dry blood spot. Pediatric children with cholestasis diagnose at National Taiwan University Hospital during admission or out-patient clinic will be collected for the Phase I study. 5ml of venous blood will be collected for measurement of disease markers during routine follow-up at National Taiwan University Hospital outpatient clinic. Dried blood spot (DBS) specimens are collected from patients by applying a whole blood, drawn by lancet from the finger, heel or toe, a provided filter paper. To evaluate the stability of disease markers on DBS, a total 10 blood spots (each blood spout contain 50 - 75 microL of blood) will be applied on the filter paper at day 0. The collected blood spots samples of a single patient at day 0 will be evaluated at the day of DBS collection and followed by day 3, day 7, 6 months and 1 year after sample collection. The purpose of repeat measurement of single patient sample at different time point is to evaluate the possible effect of time effect on the accuracy of the data. 5 blood spots are separated and protected from light with a light blocking envelope to compare the light effect on disease markers degradation (Table 1). Serum disease markers measured with conventional method will be served as reference and compared with DBS samples at different time points. 30 patients will be collected to validate the correlation between serum and DBS disease markers level. Phase II - Pilot study In the pilot study, we aim to develop dry blood spot method for the screening of neonatal cholestasis. Children with neonatal cholestasis disease previously diagnosed at Department of Pediatrics, National Taiwan University Children's Hospital from 2007 or newly diagnosed children will be recruited retrospectively from chart review. Patients with indirect type hyperbilirubinemia and healthy neonates will be enrolled as control. We will analyze neonatal cholestasis and control patients dry blood spot screening test after birth to quantify disease markers level. ROC curve analysis will be conducted on bilirubin quantity to find the best cutoff to screen for neonatal cholestasis. The sample size of case and control study is 20 cases and 20 controls.