Lymphadenopathy is common and usually not clinically important in and of itself. However, it can represent serious underlying disease. The challenge for clinicians is to avoid aggressive evaluation and biopsy of most children, while making timely, specific diagnoses when appropriate. This topic will provide guidelines for evaluating peripheral lymphadenopathy in children. The guidelines are intended to supplement clinical judgment in the absence of research that directly addresses how children with unexplained lymphadenopathy should be evaluated. The causes of peripheral lymphadenopathy and cervical lymphadenitis in children are discussed separately. (See "Peripheral lymphadenopathy in children: Etiology" and "Cervical lymphadenitis in children: Etiology and clinical manifestations".)
The causes and evaluation of peripheral lymphadenopathy in adults also are discussed separately. (See "Evaluation of peripheral lymphadenopathy in adults".)
Overview — The cause of lymphadenopathy often is obvious after a complete history and physical examination. Important aspects of the history and examination include symptoms and signs suggestive of infection and/or systemic disease, and the location, size, consistency, fixation, and tenderness of the lymph nodes.
For most children seen in primary care settings, lymphadenopathy is self-limited and does not require laboratory diagnosis. In contrast, prompt and extensive evaluation may be warranted for children seen in referral centers, especially those with rapidly changing nodes and other worrisome symptoms and signs. Laboratory testing can be used to confirm a diagnosis that is suspected on the basis of the history and physical examination (eg, throat culture for group A streptococcal pharyngitis, heterophile antibodies or specific titers for Epstein-Barr virus or cytomegalovirus mononucleosis, serology for Bartonella henselae for cat scratch disease). For cases in which the lymphadenopathy remains unexplained after the initial history, examination, and laboratory tests, additional laboratory tests and lymph node biopsy may be necessary (algorithm 1 and algorithm 2 and algorithm 3 and algorithm 4).
Treatment with glucocorticoids must be avoided before a definitive diagnosis is made. Glucocorticoid treatment could mask or delay the histologic diagnosis of leukemia or lymphoma. Glucocorticoids typically are used during the induction phase of chemotherapy for these disorders, and patients who are pre-treated are assigned to a higher risk category or may be ineligible for a clinical trial. (See "Overview of the treatment of acute lymphoblastic leukemia in children" and "Overview of Hodgkin lymphoma in children and adolescents".)