We present the 15th case reported worldwide and 3rd case reported in Latin America of immune thrombocytopenic purpura associated with Type 1 diabetes mellitus in Scopus, MEDLINE, and SciELO. An 11-year-old male patient of mixed ethnicity with immune thrombocytopenic purpura, Type 1 diabetes mellitus, and gastritis due to H. pylori presented to the emergency room with petechiae, ecchymosis, and gingival and conjunctival bleeding that had been worsening for the past three months. The patient had a body mass index of 18.85 kg/m2 (P75). A biochemical analysis showed 1×109 platelets/L, increased prothrombin time, increased partial thromboplastin time, and an HbA1C of 7.84% on admission. He was prescribed a single dose of intravenous methylprednisolone 750 mg in 100 mL of NaCl and daily oral 50 mg prednisolone, with intravenous 250 mg tranexamic acid every eight hours. The patient’s glycemi...