Case report: Kikuchi-fujimoto disease presenting with persistent fever and generalized lymphadenopathy in an adolescent girl

Introduction: Kikuchi-Fujimoto disease, or histiocytic necrotising lymphadenitis, has an indeterminate aetiology, with potential autoimmune or viral precipitating factors. The diagnosis necessitates a substantial level of clinical suspicion owing to its generic manifestation and the imperative to rule out viral and neoplastic aetiologies. We present a case of a 16-year-old female with persistent fever, cervical and axillary lymphadenopathy, and urticarial eruptions, ultimately diagnosed with Kikuchi-Fujimoto disease following excisional lymph node biopsy. Case Presentation: A 16-year-old female presented to the outpatient department with a 1.5-month history of high-grade fever, cephalalgia, myalgia, and anorexia. A painful mass was identified in her left axilla, accompanied by cervical swellings. Facial and thoracic rashes manifested one week prior to presentation. Following ineffective empirical treatment at a different hospital, she was admitted for additional evaluation. Palpation indicated painful left axillary lymphadenopathy and enlarged cervical lymph nodes at levels II and IV. Papular and urticarial eruptions affected the chest and face. Soreness in the upper belly was detected during the systemic examination; however, cardiovascular, respiratory, and neurological assessments yielded normal results. The complete blood count, liver function tests, kidney function tests, and chest X-ray results were all normal. Culture of sterile urine and blood samples. Elevated ESR (40 mm/hr) and CRP (80.8 mg/L). CECT of the abdomen revealed hepatomegaly, moderate ascites, and mesenteric lymphadenopathy, while CECT of the chest showed necrotic axillary lymphadenitis. The ANA and Mantoux tests yielded negative results. Serology results indicate negative HIV, HBsAg, and HCV. General anaesthesia was employed for the excisional biopsy of the left axillary lymph node. Histopathological findings of necrotising lymphadenitis indicated Kikuchi disease, corroborated by immunohistochemistry. The initial therapy comprised intravenous antibiotics and paracetamol. She defervesced and was discharged after stabilisation. Naproxen was used for fever during the follow-up. We initiated and gradually reduced oral steroids (Prednisolone 30 mg). She has shown clinical improvement and has remained asymptomatic for one month. Conclusion: In adolescents exhibiting protracted fever, lymphadenopathy, and rash, Kikuchi-Fujimoto disease must be contemplated following the exclusion of more prevalent causes. Excisional lymph node biopsy is essential for diagnosis, and prompt commencement of anti-inflammatory treatment can lead to full recovery.