Abstract
This study evaluates the prevalence and implications of Non-thyroidal Illness Syndrome (NTIS) in children with acute lymphoblastic leukemia (ALL), marking a focus shift towards pediatric patients who have been less studied in this context. Through a prospective analysis of 96 newly diagnosed ALL patients against healthy controls, we assessed thyroid function at diagnosis and after induction chemotherapy. Our findings highlight a significant reduction in T3/FT3 and FT4 levels in the ALL group, with NTIS prevalence jumping from 44.8% pre-chemotherapy to 74.2% post-chemotherapy, illustrating the profound impact of treatment-related factors and inflammation on thyroid health. Unlike previous beliefs, NTIS's occurrence was independent of ALL risk categories and induction therapy outcomes. Factors like elevated C-reactive protein, low serum albumin, and lymphoblast count emerged as NTIS risk indicators. Most thyroid dysfunctions normalized post-chemotherapy without needing hormonal interventions, suggesting a transient NTIS that favors conservative management focused on long-term monitoring. This study not only confirms the high incidence of NTIS in pediatric ALL patients but also challenges existing thyroid health management paradigms in pediatric oncology, calling for nuanced treatment approaches.