Lymph-node-first presentation of Kawasaki disease in a 12-year-old girl with cervical lymphadenitis caused by Mycoplasma pneumoniae: A case report

BACKGROUND: To the best of our knowledge, cases of Kawasaki disease (KD) occurring at the age of 12 are rare, even in Asia where the incidence of KD is high. We report a case of lymph-node-first presentation of KD (NFKD) in a 12-year-old girl with Mycoplasma pneumoniae (M. pneumoniae) infection who presented with prolonged fever and lymphadenitis refractory to macrolide antibiotics. CASE SUMMARY: A previously healthy 12-year-old girl presented with fever, myalgia, sore throat, swelling, and tenderness on the right side of the neck. She was initially diagnosed with lymphadenitis caused by M. pneumoniae refractory to macrolide antibiotics. She had elevated brain natriuretic peptide (BNP) levels. Finally, the patient was diagnosed with KD. After receiving intravenous immunoglobulin, the fever resolved, and her symptoms improved. CONCLUSION: NFKD should be differentiated from adolescent lymphadenitis presenting with prolonged fever by checking the BNP level early.