Three-Month History of Lymphadenopathy Caused by Bartonella henselae in a 13-Year-Old Following a Dog Scratch

We reported the case of a 13-year-old immunocompetent boy presenting with a right cervical neck mass. He complained of fatigue, back pain, coughing, and a right neck mass persisting for three months. He did not have a fever, but his parents reported he had lost 20 lbs. in the past six months without any change in diet or appetite. They are also very concerned about the risk of malignancy. During the initial work-up, there was no abnormality in the complete blood count. During the follow-up visit 10 days later, he complained of new-onset dysphagia and throat pain. The mass was about 5 cm on the right neck, poorly mobile, and mildly tender to palpation. It looks significantly different compared to the first visit. Blood serology tests were indicated, and titers of cytomegalovirus (CMV), Epstein-Barr virus (EBV), and toxoplasma were not reactive. However, serology detected that IgM and IgG titers to <i>Bartonella henselae</i> were ≥1:20 and ≥1:1024, respectively. A fine needle aspiration (FNA) of the mass on the same day revealed lymphoid proliferation. Afterward, the patient was treated with amoxicillin-clavulanic acid for two weeks. After three weeks, the mass almost disappeared, and the patient reported a remarkable improvement in symptoms. This case report is a helpful reminder that <i>B. henselae</i> should be suspected on the differential diagnoses in a case of lymphadenopathy associated with non-specific symptoms such as fatigue, back pain, and weight loss.