thymic involution
Pronunciation: in-vuh-LOO-shuhn
Age-related shrinkage of the thymus gland that begins in childhood, affecting T-cell production and immune competence.
Full Definition
The progressive atrophy and fatty replacement of thymic tissue that begins during adolescence and continues throughout life. In pediatric immunology, understanding thymic involution is important because it affects T-cell production and diversity, potentially impacting immune responses to vaccines and infections in older children and adolescents. The process is accelerated by stress, malnutrition, and certain medications, making it clinically relevant in pediatric populations with chronic diseases.
Usage
Usage note: Involution specifically refers to shrinkage due to physiological aging, not pathological destruction.
In Context
- "Premature thymic involution was observed in adolescents with chronic inflammatory bowel disease." — clinical research study
- "The radiologist noted age-appropriate thymic involution on the chest CT scan." — radiology report