Abstract
Vitamin B12 deficiency is a potentially severe condition with clinical manifestations ranging from nonspecific symptoms, such as asthenia and glossitis, to severe hematological problems, including pancytopenia and megaloblastic anemia. One of the rare phenomena associated with this condition is pseudo-thrombotic microangiopathy (pseudo-TMA), which can mimic diseases such as thrombotic thrombocytopenic purpura (TTP), leading to possible misdiagnosis and inappropriate treatment. In this article, we present the case of a 62-year-old man with a history of intravenous drug use, untreated hepatitis C, smoking, and alcoholism. The patient was admitted to the emergency department with progressive asthenia, fever, and disorientation. Laboratory findings revealed severe pancytopenia, schistocytes on the peripheral blood smear, and elevated lactate dehydrogenase levels, suggesting a microangiopathic condition. After investigation, a severe deficiency of vitamin B12 and folate was identified, and the condition was diagnosed as pseudo-TMA secondary to this deficiency. The treatment consisted of intramuscular vitamin B12 administration, resulting in the gradual normalization of the blood count and resolution of symptoms. This case highlights the importance of considering vitamin B12 deficiency in the differential diagnosis of patients with hemolytic anemia and thrombocytopenia, avoiding unnecessary interventions, such as plasmapheresis, and allowing for a quick and effective recovery with appropriate vitamin replacement.