Clinicopathologic correlation of epidemiologic and histopathologic features of pediatric bacterial lymphadenitis.

CONTEXT: Infection is a common cause of lymphadenopathy in children and has numerous microbial etiologies. Lymph node biopsy is considered a keystone in arriving at a definite diagnosis. An accurate differential diagnosis from a lymph node biopsy can expedite diagnosis and minimize ancillary testing.

OBJECTIVE

To assess and compare the histopathologic and epidemiologic features of common and uncommon pediatric bacterial lymphadenitis.

DESIGN

We searched our database for surgical specimens that had a positive identification of bacteria during an 8-year period. The chart was reviewed to assess the pathogen identified and epidemiologic data. The archival tissue sections were reviewed and the histopathologic findings described for each pathogen.

RESULTS

The review of 368 pediatric lymph node biopsies identified 33 cases with a bacterial infection. These comprised 21 cases of Mycobacterium avium complex (60%), 1 of Mycobacterium fortuitum (3%), 7 of Bartonella henselae (20%), 2 of Yersinia enterocolitica (7%), 1 of Francisella tularensis (3%) and 1 of Streptococcus pyogenes (3%).

CONCLUSIONS

Each of these infectious lymphadenitides had distinct epidemiologic and histopathologic features that are discussed in this report.