KFD is a rare lymphohistiocytic disorder due to cervical inflammatory lymphadenitis (or axillary region and even other location seldom) with an unknown etiopathogenesis, that is most commonly seen in young Asiatic people (male/female=1:1, despite some data suggest it is more frequent in women). Some HLA class II genes are more frequent in patients with KFD. In particular, the incidence of DPA1*01 and DPB1*0202 alleles is significantly higher in patients with KFD than in healthy control subjects. It is mainly characterized by lymphadenopathy, fever, nocturnal sweats, myalgia, weight loss, and arthralgia, and commonly follows a self-limited course. Less frequently symptoms observed include cutaneous lesions, hepatosplenomegaly, central nervous system impairment and haemophagocytic syndrome. The laboratory and radiologic tests available for the diagnosis are nonspecific. The common laboratory abnormalities are leukopenia, usually neutropenia; anaemia; thrombocytopenia; elevated C-reactive protein and erythrocyte sedimentation rate; impaired liver function; and atypical lymphocytes on peripheral blood smear.
This disease is misdiagnosed as malignant lymphoma in up to one-third of cases and is associated with the development of systemic lupus erythematosus (SLE) and other autoimmune diseases.The differential diagnosis is challenging as many other conditions such as malignant lymphoma, metastatic disease, tuberculosis and infectious lymphadenopathies can present in a similar way. KFD is considered a self-limiting disease: spontaneous regression may occur between 1–6 months (4). In more severe cases, nonsteroidal anti-inflammatory drugs (NSAIDs) and/or steroids treatment has proven beneficial.