Immunopathology of Kikuchi–Fujimoto disease: A reappraisal using novel immunohistochemistry markers

Abstract

Aims Kikuchi–Fujimoto disease (KFD) is a self‐limited disease characterised by destruction of the lymph node parenchyma. Few studies have assessed the immunohistological features of KFD, and most employed limited antibody panels that lacked many of the novel immunohistochemistry markers currently available. Methods and results We used immunohistochemistry to reappraise the microanatomical distribution of plasmacytoid dendritic cells (pDCs), follicular helper T cells and cytotoxic T cells, B cells, follicular dendritic cell (FDC) meshworks, and histiocytes in lymph nodes involved by KFD. The study group consisted of 138 KFD patients (89 women; 64.5%) with a median age of 27 years (range, 3–50 years). Cervical lymph nodes were most commonly involved, in 108 (78.3%) patients. The numbers of pDCs were increased, predominantly around and within apoptotic areas and the paracortex, and tapering off within xanthomatous areas. pDCs formed sizeable tight clusters, most notably around apoptotic/necrotic areas. T cells consisted mostly of CD8‐positive cells with predominant expression of T‐cell receptor‐β. There were notable increases in the numbers of CD8‐positive T cells within lymphoid follicles, and their numbers correlated with alterations in FDC meshworks (P < 0.001). The number of follicular helper T cells was decreased within distorted FDC meshworks. CD21 highlighted frequent distortion of FDC meshworks, even in lymph node tissue that was distant from apoptotic/necrotic areas. Distorted FDC meshworks spanned all morphological patterns, and FDC meshwork characteristics (intact; distorted; remnant/nearly absent) correlated with morphological patterns (P < 0.01). Conclusions The immunohistological landscape of KFD is complex and characterised by increased numbers of pDCs that frequently cluster around apoptotic/necrotic foci, increased numbers of cytotoxic T cells, and substantial distortion of FDC meshworks.

Kikuchi Fujimoto disease: A rare case of recurrence

“…Microscopic examination can also demonstrate paracortical foci of histiocytic infiltrate, with characteristic absence of neutrophils and eosinophils with few or no plasma cells [19]. The immunohistologic landscape of KFD is complex and characterized by increased numbers of plasmacytoid dendritic cells that frequently cluster around apoptotic/necrotic foci, increased cytotoxic T-cells, and substantial distortion of follicular dendritic cell mesh works [25]. However, in the case reported, histological examination of the cervical lymph node revealed necrotizing lymphadenopathy with severe plasmacytosis.…”

A Malignant Mimicker: Features of Kikuchi-Fujimoto Disease in the Pediatric Population

“…Additionally, we found the increase in pDCs to be patchy and proportionally lower than the increased pDCs typical of KFD, findings supported by prior studies. [26][27][28][29][30][31] For example, Rollins-Raval et al 28 reported fewer pDCs in viral infections (including CMV, HIV, Hepatitis C and a case of chronic HIV and EBV) compared to KFD and other causes of granulomatous inflammation. pDCs are known to migrate from the bone marrow to T-cell rich areas of lymph nodes.…”

A Case of Kikuchi-Fujimoto Disease in a 7-Year-Old African American Patient: A Case Report and Review of Literature

“…The histiocytes have crescent-shaped nuclei and phagocytosed debris, which differentiate it from other lymphadenopathies such as tubercular lymphadenitis or lymphoma [ 7 , 9 , 11 ]. Some previous research proposed that cytotoxic T cells are important in the pathogenesis of, and on IHC, CD8-positive T cells were predominant in the lymphoid follicles [ 17 ]. Our IHC also confirmed a dominance of CD8-positive T lymphocytes.…”