17 yrs old male with neck lymphadenopathy and Lyme disease *under treatment). 2 biopsies were obtained. Both original reports: "Reactive changes". History of multiple purulent tonsilitis. Blood: ESR 65; WBC 13.6x10(9); LDH 617 U/l; Hb 106g/l; BM aspirate: leukemoid reaction.  
HISTO: Some expanded parakortical areas with large and highly atypical (binucleated) immunoblasts with basophilic macronucleoli with CD20+ EBV LMP1- and CD3+? immunophenotype. Activated CD30+dim cells. CD30+CD15+ typical RS or H cells are absent. Ki67 activity ~30% in the nidus. Eos and granulocytes in open sinus. Focal immature histyocytosis in the sinuses.  
PICTURES: Nidus 1 (with more prominent CD20+ immunoblasts) and Nidus 2 (more closed to sinus). CD3 is right-sided in "CD3 CD20 SCAN".  
 
PROPOSAL: Reactive lymphadenopathy with prominent immunoblastic reaction.