2015 · Indian journal of endocrinology and metabolism · open access
Congenital hypothyroidism
Agrawal et al.
The finding, in our words
Dried capillary blood spots taken by heel prick are the established standard for neonatal congenital hypothyroidism screening, with abnormal results requiring immediate confirmatory venous testing. Prompt levothyroxine treatment based on early microsampling prevents mental retardation, as IQ correlates inversely with age at diagnosis.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
This review establishes that microsampling across blood, saliva, urine and stool matrices offers validated workflows and regulatory recognition for human biomonitoring comparable to conventional methods. It finds that these decentralised approaches enhance participant acceptability and enable screening in remote or low-resource settings.
Among 8007 neonates screened using dried blood spots, the study identified prevalence rates for congenital hypothyroidism (1:2002), congenital adrenal hyperplasia (1:2002) and G6PD deficiency (1:900), with abnormal results confirmed by venous sampling. This demonstrates the practical utility of microsampling for decentralised newborn screening and subsequent clinical management.
Analysis of dried blood spots from 813 newborns demonstrated that extremely preterm infants have markedly elevated corticosterone and 17-hydroxyprogesterone, with the latter showing the strongest inverse correlation with gestational age, indicating these precursors better reflect adrenal immaturity than cortisol alone. This validates DBS as a practical tool for guiding postnatal steroid therapy in preterm infants by helping clinicians distinguish physiological adrenal immaturity from true insufficiency.
Home DBS sampling gave testosterone results that agreed well with venous blood in men on intramuscular testosterone undecanoate, but showed falsely high values in those using topical gel, likely from skin contamination. Patients preferred home collection for its convenience, suggesting DBS is viable for decentralised monitoring of injectable testosterone if patients are taught proper technique.
Capillary dried blood spots yielded reference ranges for testosterone, androstenedione, 17α hydroxyprogesterone and progesterone in healthy premenopausal women, with lower concentrations in users of systemic hormonal contraceptives and cycle-related variation for 17OHP and P4. These ranges enable screening for disorders of sex development using less invasive microsampling.