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Aseptic Meningitis Revealing Isolated Kikuchi-Fujimoto Disease

Introduction: Kikuchi-Fujimoto’s disease (KFD) or histiocytic necrotizing lymphadenitis is a rare entity that may represent a real diagnostic challenge for the clinician because of its highly polymorphous and sometimes unusual presentations. We report an original observation of KFD with aseptic meningitis as inaugural manifestation. Case report: 30-year-old woman, without pathological medical history, was hospitalized via the emergency department for exploration of a meningeal syndrome with cervical lymphadenopathies. The lumbar puncture showed aseptic meningitis: clear, normotensive cerebrospinal fluid with leukocytes at 28/mm3 (90% lymphocytes), red blood cells at 2/mm3, proteinrrhachia at 0.58 g/l, glucorrachia at 4 mmol/l for venous glycemia at 8 mmol/l, and negative direct examination and culture. Cerebromedullary MRI and cerebral angio-MR were without abnormalities. Further infectious and immunological investigations were negative. Cervical lymph node biopsy showed histological and Immunohistochemical aspects suggesting KFD. Treated with systemic corticosteroids, the evolution was favorable with no recurrence. Conclusion: KFD-associated aseptic meningitis remains rare, and the inaugural forms are exceptional and often difficult to diagnose. A better knowledge of this association avoids unnecessary investigations, recurrence, and improves the prognosis of the disease.


ISSN: 2637-6628
Introduction Described for the first time in 1972 by Kikuchi M and Fujimoto Y [1,2], Kikuchi-Fujimoto disease (KFD) is a very rare necrotizing histiocytic lymphadenitis [3] which is classically characterized by a febrile polyadenopathy with a marked inflammatory biological syndrome in young subject, mainly Asian women. KFD may be isolated [4] or associated with several other systemic diseases of a dysimmune nature, particularly systemic lupus erythematosus [5,6]. Systemic disorders, including neurological ones, during this disease are exceptional and represent a real diagnostic challenge for clinicians, especially in the inaugural and isolated forms [1][2][3][4].
Although recognized to be the most frequent neurological event in this disease, KFD-associated lymphocytic meningitis remains rare, and the inaugural forms are exceptional and often difficult to diagnose [7][8][9]. We report an original observation of aseptic meningitis inaugural of an isolated KFD in a 30-year-old Tunisian woman.

Case report
A 30-year-old Tunisian woman, without pathological medical history, was hospitalized via the emergency department for exploration of a meningeal syndrome. The history of his illness dates back two days before his hospitalization, by the appearance of headaches with fever and vomiting not improved by the symptomatic treatment. The somatic examination found a patient conscious, well oriented, without focal neurological deficit, feverish at 39°C, significant stiffness of the neck, with photophobia, sonophobia, and multiple cervical adenopathies slightly sensitive. The ENT and bucco-dental examination were without abnormalities. The biology showed leukocytosis at 15 600/mm 3 with 85% neutrophils, a marked biological inflammatory syndrome with a high erythrocyte sedimentation rate at 135mm/H1, a C-reactive protein at 28 mg/l and a hyperfibrinemia at 8 g/l. The other basic bioassays were without abnormalities: hemoglobin, platelets, blood glucose, serum calcium, ionogram, liver enzymes, muscle enzymes, creatinine, serum protein electrophoresis, and urine analysis. Chest X-ray and electrocardiogram were normal. The ophthalmic examination with fundus of the eye did not shows any papillary edema.
The lumbar puncture showed a clear, normotensive anti-CD68 antibodies was positive. Thus, the diagnosis of aseptic lymphocytic meningitis within the framework of an isolated KFD was retained and the patient was treated with oral corticosteroids at a dose of 1 mg/kg/day for four weeks followed by gradual decrease, in association with hydroxychloroquine at a dose of 400 mg/day. The evolution was rapidly favorable with apyrexia and disappearance of meningeal signs after two days and total regression of cervical lymphadenopathies after two weeks. The lumbar puncture performed at one month was strictly normal, and no recurrence has been noted for two years now.

Discussion
Non-infectious aseptic meningitis is a real diagnostic challenge in current medical practice because of the absence of specific clinical and biological signs and the multitude of possible etiologies [10,11]. The main causes of these meningitis are: systemic diseases (connective tissue diseases, primary vasculitis and granulomatosis), cancers and hematological malignancies (neoplastic meningitis), and drug intake (drug-induced meningitis) [10]. Among the systemic diseases, KFD remains an exceptional etiology of aseptic meningitis: indeed, only one case of aseptic meningitis was secondary to KFD in the series of 180 cases of aseptic meningitis of Jarrin I et al. [12] a frequency of 0.55%. Similarly, during a KFD, lymphocytic aseptic meningitis remains an exceptional event: only two cases in the series of 91 patients with KFD of Dumas G (2.1%) [8], and only two observations in the series of 69 cases of KFD of Nakamura I et al. [7] (2.8%).

Conclusion
As rare as it is, Kikuchi-Fujimoto disease as possible etiology of aseptic meningitis must be known. This knowledge will in many cases avoid unnecessary investigations, recurrence, specific or nonspecific complications, and improve the prognosis of the disease.