A Rare but Important Cause of Prolonged Fever and Lymphadenopathy

Case Presentation:

A healthy 24 year old Chinese male was admitted for fever for 3 weeks. His symptoms were associated with chills and rigors, night sweats and loss of appetite.

On physical examination, he had enlarged painful cervical and left axillary lymph nodes. Spleen and liver was not enlarged. His laboratory investigations were normal except for mild leucopenia (WBC count-3.23×10(9)/L) (NR 4.0-10×10(9)/L). Blood film showed lymphopenia. Atypical lymphocytes were also seen. He had an elevated C-Reactive Protein (67.1MG/L) (NR 0.2-9.1MG/L) and Lactate dehydrogenase (1594 U/L) (NR 222-454 U/L). Infectious work up which included a HIV screen, Epstein–Barr virus PCR and Cytomegalovirus PCR were negative. Autoimmune work up which included Antinuclear antibody was also negative. CT scan (Neck/chest /abdomen and pelvis) revealed bilateral enlarged cervical and axillary lymph nodes.

Our differential diagnosis was that of lymphadenopathy secondary to lymphoma or tuberculosis. We proceeded to do an excisional biopsy of the right cervical lymph node. Biopsy showed reactive lymphoid hyperplasia with focal histiocytic necrotizing lymphadenitis suggestive of Kikuchi-Fujimoto disease. To our surprise, there were no features suggestive of malignancy or tuberculosis. Patient improved with supportive treatment.

Discussion:

Patients with Kikuchi-Fujimoto disease often present with prolonged fever and cervical lymphadenopathy. Patients may experience systemic symptoms which include weight loss, malaise, chills, night sweats and arthralgia. Common laboratory findings include that of anemia, leucopenia, raised C-Reactive Protein and Lactate dehydrogenase. The clinical and laboratory findings of Kikuchi-Fujimoto disease mimic more sinister conditions such as lymphoma and tuberculosis.  It is important to clinch the diagnosis as there have been case reports of misdiagnosed patients who were subjected to chemotherapy.  

Diagnosis is made by excision biopsy of the lymph node.  Histology usually shows paracortical foci often with necrosis and a histiocytic cellular infiltrate.

Kikuchi-Fujimoto disease is a self-limiting disease that usually resolves in 1 to 6 months.  Treatment is usually supportive with paracetamol and NSAIDs. Although there is no established treatment, oral corticosteroids are occasionally used for patients not improving with supportive treatment. There have also been case reports of patients requiring immunoglobulins, hydroxychloroquine and intravenous methylprednisolone.

Patients should be followed up for a few years as they can have recurrences. Also there have been various reports of these patients developing Systemic Lupus Erythematosus.

Conclusions:

It is important to consider Kikuchi-Fujimoto disease as a differential diagnosis in patients with fever and cervical lymphadenopathy. This would help to avoid patients with the disease being subjected to unnecessary treatment and investigations.