Kikuchi-Fujimoto's disease involving mesenteric nodes: a report and review of literature
Executive Summary
Kikuchi-Fujimoto Disease (KFD), or histiocytic necrotizing lymphadenitis, is a rare, benign, and self-limiting condition typically characterized by cervical lymphadenopathy and fever. While the disease most commonly affects the cervical lymph nodes of young women, this briefing examines a highly unusual presentation involving the mesenteric (intra-abdominal) lymph nodes in a male adolescent.
Intra-abdominal involvement is extremely rare, with only 17 cases reported in world literature at the time of this study. Due to its presentation—often mimicking acute appendicitis or more severe conditions like lymphoma and tuberculosis—KFD remains a diagnostic challenge. Diagnosis is definitively established through histopathological examination and immunohistochemistry (IHC). Management is primarily supportive, though low-dose corticosteroid therapy is effective in resolving persistent symptoms.
Disease Overview and Pathogenesis
Kikuchi-Fujimoto Disease was independently described in 1972 by Kikuchi and Fujimoto. It is characterized by necrotizing lymphadenitis with predominant histiocytic infiltration.
Standard Clinical Presentation
Demographics: Primarily affects young people, with a higher prevalence in Asiatic populations and a historical predilection for females.
Symptoms: Regional lymphadenopathy (usually cervical), low-grade fever, and night sweats.
Course: Benign and self-limiting, typically evolving over two to three weeks.
Aetiology
The exact cause remains unknown, though several hypotheses exist:
Viral/Infectious Agents: Potential associations include Epstein-Barr virus, herpes viruses 6 and 8, and Toxoplasma gondii.
Hyper-immune Reaction: KFD may represent a hyper-immune response to various organisms in susceptible individuals.
Autoimmune Link: Negative tests for antinuclear antibodies and rheumatoid factor often help distinguish KFD from autoimmune diseases, though it shares some histopathologic features with Systemic Lupus Erythematosus (SLE).
Case Presentation: Mesenteric Involvement
The documented case involves a moderately built and nourished male adolescent presenting with:
Symptoms: Persistent fever (up to 104°F) for three weeks, colicky abdominal pain (localized in the central and right lower abdomen), painful swallowing, and reduced appetite.
Clinical Findings: Tenderness in the right lower abdomen and paraumbilical regions. Notably, there was an absence of peripheral lymphadenopathy (cervical, axillary, or inguinal).
Surgical Observations: Laparoscopy revealed a small amount of yellowish free fluid in the pelvis, peritoneal congestion, and a "conglomerated group" of enlarged, matted mesenteric lymph nodes in a thickened ileocolic mesentery.
Diagnostic Investigations
Diagnosis of intra-abdominal KFD is difficult because radiological findings are non-specific.
Laboratory and Imaging Findings
Histopathology: The Diagnostic Standard
The definitive diagnosis of KFD is made via the histological examination of resected lymph nodes. The case study identified three evolving stages of KFD as described by Kuo: proliferative, necrotizing, and xanthomatous.
Key Histological Hallmarks:
Loss of nodal architecture.
Presence of eosinophilic necrosis and karyorrhectic/karyolytic debris.
Collections of transformed lymphocytes, histiocytes, and plasmacytoid monocytes.
Absence of Neutrophils: A critical differentiator from bacterial infections.
Absence of Giant Cells/Granulomas: Helps rule out tuberculosis.
Immunohistochemistry (IHC)
IHC is mandatory to rule out malignancy and other mimics. In this case, staining showed:
CD 68 and CD 3 Positive: Indicates a predominance of histiocytes and T-lymphoid cells.
CD 20 Weakly Positive: Indicates few B-lymphoid cells.
CD 15 Negative: Reflects the paucity of neutrophils.
Differential Diagnosis
KFD is frequently misdiagnosed due to its clinical similarity to other conditions.
Management and Prognosis
KFD is a self-limiting disease requiring a careful but systematic approach to diagnosis to avoid unnecessary or prolonged treatments for conditions like tuberculosis.
Primary Treatment: Symptomatic and supportive care is usually sufficient.
Pharmacotherapy: For patients with persistent fever or distressing symptoms, low-dose corticosteroid therapy (e.g., prednisolone) is effective. In the examined case, symptoms resolved within three weeks of starting steroids.
Prognosis: Excellent. Postoperative recovery is typically remarkable. Follow-up ultrasound examinations in this case showed no residual lymphadenopathy, and the patient remained asymptomatic at a one-year review.
Learning Points for Clinical Practice
Fever of Unknown Origin: KFD should be considered in the differential diagnosis of unknown fever, especially when associated with mesenteric adenopathy.
Diagnostic Suspicion: A high degree of clinical suspicion is essential, as mesenteric KFD is rare and can mimic acute appendicitis.
Mandatory Biopsy: Diagnosis cannot be made on clinical or radiological grounds alone; it requires histological examination of resected nodes.
Steroid Application: While KFD is self-limiting, low-dose steroids are a viable intervention for persistent fevers.
