1 - Unidade de Infeciologia Pediátrica, Hospital de Dona Estefânia
2 - Serviço de Pediatria, Centro Hospitalar de Leiria
3 - Serviço de Anatomia Patológica, Hospital São Jose CUHLC
4 - Departamento de Doenças Infecciosas, Instituto Nacional de Saúde Dr. Ricardo Jorge
- 37th Meeting of the European Society for Paediatric Infectious Diseases (ESPID)
Background: Kikuchi Fujimoto’s disease (KFD) or histiocytic lymphadenitis is especially rare in paediatrics. Although it is a self-limited and benign disease, its differential diagnose is vast including lymphoma, various infections and autoimmune diseases.
Case Report: Previously healthy, 15 year-old male admitted with fever for 18 days, weight loss of 2.7kg and painful cervical, axillar and inguinal lymphadenopathies for the last four weeks. He lived in a rural area and had contact with rabbits. Etiologic investigation revealed leukopenia with neutropenia (0,84x10^9/L), thrombocytopenia (128x10^9/L), CRP 0,75mg/L, ESR 74mm/h, ferritin 958ng/mL and high lactic dehydrogenase (726U/L). The serum was positive for Francisella tularensis antibodies by agglutination test (titre of 40) and the Brucella sp. was negative. However, a real-time multitarget TaqMan PCR, using tul4 and ISFtu2 assays were negative. He was started on doxycycline and ciprofloxacin. Other infections and autoimmune diseases were excluded. Chest X-ray, echocardiogram and bone marrow aspiration revealed no alterations. Abdominal ultrasound showed a mildly enlarged liver. Lymph node excisional biopsy showed histiocytic lymphadenitis with paracortical expansion by foamy histiocytes, highlighted with CD68 immunohistochemistry, containing phagocyted cell debris, which is compatible with KFD on the xanthomatous phase (recovery phase). The patient had resolution of fever and lymph node enlargement and F. tularensis antibodies decreased after 3 weeks (titre of 2).
Discussion: KFD causes remain unknown, although it is considered to be the result of a self-limited autoimmune process triggered by an infectious agent. In some patients it is possible to find false-positive results against several agents. It is important to be aware of KFD in the presence of FUO and lymphadenopathies. Clinical features are not specific, therefore the histological findings after excisional lymph node biopsy are essential to have a definitive diagnosis.
Palavras Chave: Doença de Kikuchi; Febre de origem desconhecida; Linfadenite Histiciocitica