Myelodysplastic syndrome with pulmonary tumor thrombotic microangiopathy in an 11-year-old male patient

Myelodysplastic syndrome (MDS) and pulmonary tumor thrombotic microangiopathy (PTTM) are independently rare in the pediatric population. This report describes an 11-year-old male patient who initially presented with respiratory distress and cardiovascular collapse. A large left main pulmonary artery embolus and multiple, smaller pulmonary thromboemboli were widely dispersed throughout both lungs. Despite aggressive supportive care, he died within seven hours of admission. A complete postmortem examination was performed, leading to the diagnoses of primary MDS and microthrombi in the lungs, including the characteristic fibroproliferative lesions seen in PTTM. Individually, both conditions are extremely uncommon, and therefore the coincidence of these 2 conditions in a child is singularly unique.