Discussion
Kikuchi-Fujimoto disease (KFD) is a histiocytic necrotizing
lymphadenitis, which was described in 1972 by Kikuchi and Fujimoto in
Japan.2 KFD is a rare and benign disease with unknown
etiology.4 Although the etiology of disease is still
unclear, viral infections (Epstein-Barr virus, Cytomegalovirus,
rhinovirus, rubella virus, and HIV) 5 and autoimmune
diseases (SLE, Polymyositis, Rheumatoid arthritis, Still’s disease, and
Sjogren’s syndrome)6 are proposed as possible triggers
for KFD.
The most common clinical presentations of KFD are lymphadenopathy
(79-94%), fever (35-67%), cutaneous rashes (4-32.9%), arthralgia
(7-34.1%) and hepatosplenomegaly (3-14.8%).2 Less
common presentations, including arthritis, weight loss, loss of
appetite, hepatosplenomegaly, and sweating.4 Our
patient experienced lymphadenopathy, fevers, night sweats, myalgia,
weight loss and hair loss. The most frequent laboratory findings of KFD
are elevated levels of ESR (78.9%), CRP (38.3%) and LDH
(52.5-81.5%).2 Moreover, the literature has reported
lymphopenia (63.8%), thrombocytopenia (5.4-19%) and leukocytosis
(2-5%) in patients.2,5 Our patient had leukopenia,
severe anemia, elevated LDH, raised ESR and CRP. The common
presentations and remarkable laboratory changes, probably valuable along
with excisional biopsy as a gold standard of diagnosis.
The diagnosis of KFD is based on histopathologic examination of an
involved lymph node biopsy.1,4 The most common
histologic finding is the presence of areas of necrosis and apoptosis
which surrounded by CD68+ histiocytes, CD123+ plasmacytoid dendritic
cells and activated CD8+ T-lymphocytes.7 Also, absence
of neutrophils and eosinophils is an important characteristic in support
of the diagnosis.5,8 Several studies purposed that KFD
may be a clinical presentation of lupus lymphadenitis or associated with
infectious mononucleosis-like syndromes such as EBV
infection.2,5,6 Therefore, a complete work-up,
including precise clinical examination with an excisional biopsy is
recommended to rule out other serious autoimmune and infectious disease.
The long-term prognosis of KFD is good and deaths have been seen in a
few patients with systemic forms of the disease.6,8KFD usually resolves within 1-6 months with a 12.2% recurrence rate in
children.1,6 No specific treatment is known for KFD
and the most common approach is supportive therapy.2,4NSAIDs are used to relieve some of the localized signs and symptoms such
as fever and tenderness of lymph nodes. In severs forms of the disease
patients maybe benefit from corticosteroid therapy, hydroxychloroquine
or intravenous immunoglobulin.4,8
To our best knowledge, this is the first reported case of KFD, who was
affected by COVID-19. Although the association of KFD and COVID-19
cannot be confirmed in this case, considering some cutaneous
manifestations of COVID-19, such condition should not be missed.