Comparison of clinical features and EBV expression in histiocytic necrotizing lymphadenitis of children and adults.

OBJECTIVE: Histiocytic necrotizing lymphadenitis (HNL) is a self-limiting disease characterized by cervical lymphadenopathy and fever. Epstein-Barr virus (EBV) has been implicated as a cause of HNL in some reports but not in others. The aim of this study was to compare the clinical features and laboratory findings in children and adults with HNL and to evaluate the relationship between EBV infection and HNL. METHODS: The records of patients diagnosed with biopsy-confirmed HNL at Gyeongsang National University Hospital from May 2009 to December 2012 were retrospectively reviewed. Clinical features, laboratory data (blood count, biochemistry, and serology), and computed tomography findings were collected. Immunohistochemistry for CD4, CD8, CD68, and myeloperoxidase (MPO), and in situ hybridization for EBV RNA were performed on archived lymph node biopsies from pediatric and adult patients. RESULTS: A total of 16 children and 31 adults were diagnosed with HNL. Fever was present in 87.5% of children and 25.8% of adults (P<0.0001). Fever duration was longer for children (mean, 5.06 days) than for adults (mean, 0.63 days; P=0.008). Necrosis of the involved lymph nodes was observed in eight (50%) children and six (19.4%) adults (P=0.045). HNL recurred in five (31.35%) children and one (3.2%) adult (P=0.015). All had detectable CD4, CD8, CD68, and MPO immunoreactivity. EBV reactivity was higher in children (26.7%) than in adults (6.7%) without statistical support. CONCLUSIONS: There is more variability in the clinical presentation and laboratory findings in children with HNL than in adults. In particular, the degree and duration of fever was more severe in children than in adults, and necrosis of lymph nodes was more frequent in children than in adults. There was no definitive correlation between EBV reactivity and NHL. Further study of the relationship between EBV and HNL is needed with a larger number of patients.