Reactive lymphoid hyperplasia, or reactive lymphadenopathy as it is sometimes referred to, is an enlargement of the lymphoid tissue due to stimulation by antigens, according to the University of Virginia School of Medicine. It is usually reversible and exists in a benign state within the body.
The response of the lymphoid gland to stimuli varies, with the worst case scenarios showing an increase in the size and number of follicles, enlarged sinuses and the covering of the lymph node by sheets of white blood cells, or lymphocytes. The condition is common in lung biopsy, explains Jarrod Bruce et al. in Respiratory Medicine CME.