Autoimmune and medication-induced lymphadenopathies.

This article will provide a discussion of some common autoimmune disorders that could affect the lymph nodes and potentially mimic B and T-cell lymphomas. Some of these disorders are more characteristic of individuals in the pediatric age group (autoimmune lymphoproliferative syndrome, Kawasaki disease), while others present in older individuals (rheumatoid arthritis, lupus erythematosus, sarcoidosis). A common finding that groups all of these disorders together is the overall relative preservation of the architecture, a feature that can be particularly helpful to distinguish them from many B and T-cell lymphomas. Another area of interest, that will be discussed in this review, is the pathologic manifestations that can be present in lymph nodes secondary to medications. Such alterations range from 'reactive' forms of follicular, interfollicular or paracortical hyperplasia, to specific B and T-cell lymphoproliferative disorders (particularly documented in association with methotrexate and TNF-inhibitors).