Autoimmune Thyroiditis Induced by Bartonella henselae (Cat-Scratch Disease) Might Be Reversible.

INTRODUCTION: Bartonella henselae infection leads to development of cat-scratch disease (CSD) but may also trigger of autoimmune thyroiditis (AIT). CASE PRESENTATION: We describe a 4-year-old boy with a severe fever of unknown etiology, disseminated neck lymphadenopathy, and a headache. Treatment with antibiotics was employed, but finally a left tonsillectomy, selective left lymphadenectomy, and immunophenotyping were performed to exclude lymphoma. Histologic examination excluded lymphoma but revealed CSD. IgG against B. henselae and Bartonella quintana was positive. A goiter was also found and positive anti-thyroid antibodies confirmed AIT. Two months later, the thyroid was not palpable, normal on ultrasound, and both anti-thyroid antibodies were negative. The full reversibility was documented, and 6-year follow-up showed that the patient remains disease free. CONCLUSION: This is the first report that AIT triggered by B. henselae/B. qunitana might be reversible if the pathogenetic factor is eliminated at an early stage of disease.