POPULATION-BASED NEWBORN SCREENING BY DRIED BLOOD SPOT METHOD: A PROSPECTIVE OBSERVATIONAL STUDY FROM NORTH KARNATAKA

Abstract

Background: Newborn screening (NBS) using dried blood spot (DBS) methodology is a well-established public health strategy for early detection of treatable congenital disorders. Despite its proven benefits, implementation in resource limited settings remains variable, necessitating region-specific feasibility studies. Objective: To evaluate the feasibility, screening yield, and associated maternal and demographic factors of a mandatory DBS-based newborn screening program in a tertiary care setting in North Karnataka. Methods: This prospective observational study included 1,000 newborns screened between January and December 2024 at S. Nijalingappa Medical College, Bagalkote. DBS samples collected between 24–72 hours of life were analyzed for phenylketonuria (PKU), glucose-6-phosphate dehydrogenase (G6PD) deficiency, galactosemia, congenital hypothyroidism (TSH), and hemoglobinopathies using standardized laboratory protocols. Maternal and sociodemographic data were recorded. Statistical analysis was performed using chi-square tests, with p < 0.05 considered significant. Results: The overall screen-positive rate was 8.7% (87/1,000). Congenital hypothyroidism was the most common abnormality (3.5%), followed by G6PD deficiency (2.2%), galactosemia (1.2%), hemoglobinopathies (1.0%), and PKU (0.8%). A statistically significant association was observed between consanguinity and screen-positive outcomes (p = 0.002), while maternal age, socioeconomic status, residence, and maternal medical history showed no significant association. No significant correlation was found between screening positivity and sex or place of residence. Implementation of repeat DBS testing improved diagnostic accuracy and reduced false-positive referrals. Conclusion: Mandatory DBS-based newborn screening is feasible and effective in a resource-limited setting, with a high screening yield and strong relevance in populations with prevalent consanguinity. Expansion of such programs can significantly reduce preventable morbidity and mortality through early diagnosis and intervention.