{"title":"Improving self-collected dried blood spot specimens for phenylketonuria monitoring: a 10-year computer vision review of dried blood spot specimen quality","authors":"Nick Flynn , Stuart J. Moat , Sarah L. Hogg","doi":"10.1016/j.cca.2025.120656","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><div>Biochemical monitoring of phenylketonuria (PKU) is performed using dried blood spot (DBS) specimens, usually collected by the patient or carer. DBS quality affects DBS phenylalanine results and self-collected specimen quality may often be sub-optimal. However, it is unclear how often specimen quality affects clinical interpretation of PKU monitoring results, or whether sustained improvements in DBS quality are achievable in this setting.</div></div><div><h3>Methods</h3><div>We used a computer vision algorithm to objectively assess DBS quality in 8472 DBS specimens collected from 111 PKU patients over a 10-year period. Trends in specimen quality were analysed over time, by patient, and by frequency of specimen collection. We modelled the effect of sub-optimal DBS size on phenylalanine result classification against European PKU treatment guidelines.</div></div><div><h3>Results</h3><div>The proportion of poor-quality DBS decreased from 66.5 % to 3.2 % over a 10-year period. The median proportion of acceptable specimens returned by each patient each year improved from 28.6 % in 2015/16 to 100 %. Patients returning specimens more frequently showed better DBS quality performance, with acceptability rates of 96.3 % in patients who returned ≥10 specimens in 2024–25, compared to 78.3 % in patients who returned <5 specimens. Improvement in DBS quality reduced potential misclassification against PKU treatment guidelines due to DBS size from 3.1 % to 0.6 %.</div></div><div><h3>Conclusions</h3><div>Without training and education, DBS quality in self-collected specimens may be very poor. However, substantial improvements are achievable for PKU monitoring specimens, reducing total measurement error and the risk of incorrect clinical interpretation of results.</div></div>","PeriodicalId":10205,"journal":{"name":"Clinica Chimica Acta","volume":"579 ","pages":"Article 120656"},"PeriodicalIF":2.9000,"publicationDate":"2025-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Clinica Chimica Acta","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0009898125005352","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MEDICAL LABORATORY TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background
Biochemical monitoring of phenylketonuria (PKU) is performed using dried blood spot (DBS) specimens, usually collected by the patient or carer. DBS quality affects DBS phenylalanine results and self-collected specimen quality may often be sub-optimal. However, it is unclear how often specimen quality affects clinical interpretation of PKU monitoring results, or whether sustained improvements in DBS quality are achievable in this setting.
Methods
We used a computer vision algorithm to objectively assess DBS quality in 8472 DBS specimens collected from 111 PKU patients over a 10-year period. Trends in specimen quality were analysed over time, by patient, and by frequency of specimen collection. We modelled the effect of sub-optimal DBS size on phenylalanine result classification against European PKU treatment guidelines.
Results
The proportion of poor-quality DBS decreased from 66.5 % to 3.2 % over a 10-year period. The median proportion of acceptable specimens returned by each patient each year improved from 28.6 % in 2015/16 to 100 %. Patients returning specimens more frequently showed better DBS quality performance, with acceptability rates of 96.3 % in patients who returned ≥10 specimens in 2024–25, compared to 78.3 % in patients who returned <5 specimens. Improvement in DBS quality reduced potential misclassification against PKU treatment guidelines due to DBS size from 3.1 % to 0.6 %.
Conclusions
Without training and education, DBS quality in self-collected specimens may be very poor. However, substantial improvements are achievable for PKU monitoring specimens, reducing total measurement error and the risk of incorrect clinical interpretation of results.
期刊介绍:
The Official Journal of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC)
Clinica Chimica Acta is a high-quality journal which publishes original Research Communications in the field of clinical chemistry and laboratory medicine, defined as the diagnostic application of chemistry, biochemistry, immunochemistry, biochemical aspects of hematology, toxicology, and molecular biology to the study of human disease in body fluids and cells.
The objective of the journal is to publish novel information leading to a better understanding of biological mechanisms of human diseases, their prevention, diagnosis, and patient management. Reports of an applied clinical character are also welcome. Papers concerned with normal metabolic processes or with constituents of normal cells or body fluids, such as reports of experimental or clinical studies in animals, are only considered when they are clearly and directly relevant to human disease. Evaluation of commercial products have a low priority for publication, unless they are novel or represent a technological breakthrough. Studies dealing with effects of drugs and natural products and studies dealing with the redox status in various diseases are not within the journal''s scope. Development and evaluation of novel analytical methodologies where applicable to diagnostic clinical chemistry and laboratory medicine, including point-of-care testing, and topics on laboratory management and informatics will also be considered. Studies focused on emerging diagnostic technologies and (big) data analysis procedures including digitalization, mobile Health, and artificial Intelligence applied to Laboratory Medicine are also of interest.