Immune thrombocytopenia associated with Hashimoto thyroiditis in a pediatric patient

Immune thrombocytopenia (ITP) is one of the most commonly acquired bleeding diseases in children. Infection and autoimmune disorders are the most common causes of ITP. The pathogenic mechanism of ITP is complex and is not completely understood. Understanding the underlying causes or disorders of ITP will improve the prognosis and make therapy more targeted.An 8-year-old girl with ITP responded poorly to first- and second-line treatment. The patient showed multiple scattered petechiae, ecchymoses, and purpura in the skin and blood clots in the oral mucous membrane.The patient was diagnosed with ITP associated with Hashimoto thyroiditis.The patient was admitted to our emergency department and received platelet transfusion, IVIG, glucocorticoids and eltrombopag. The patient's thrombocytopenia resolved within 18 days after the administration of levothyroxine treatment.The patient was diagnosed with Hashimoto thyroiditis, and the platelet count recovered on the 3rd day of levothyroxine treatment. The platelet count became steadily normal with levothyroxine and prednisone treatment within 2 months of follow-up.Early identification of the underlying reasons and treatment with multiple modalities may be useful in improving the prognosis of ITP. The treatment of thyroid disease and restoration of the euthyroid state impact the clinical outcome of ITP in children.