Pancytopenia in the context of Hypothyroidism and b12 deficiency: A Case Report and Review literature

Background: This case of pancytopenia due to hypothyroidism and B12 deficiency is rare and severe as a reminder that, upon diagnosis of pancytopenia, endocrine disorders such as secondary thyroid hormone deficiency may need to be considered as a potential cause. Case Presentation: A 38-year-old male presented with progressive weakness, lethargy, and anorexia. Initial labs revealed severe pancytopenia, prompting a hematological workup. Bone marrow aspiration ruled out acute leukemia. Further investigations identified severe primary hypothyroidism (TSH: 200 mIU/L) and vitamin B12 deficiency as the underlying causes, after excluding other common etiologies. Treatment with levothyroxine and vitamin B12 was initiated. The patient showed a rapid and significant hematological response, with all cell lines improving and approaching normal ranges on follow-up, confirming the diagnosis. Conclusion: In this patient, after the diagnosis of hypothyroidism and receiving levothyroxine, we saw a better stability of the improvement of the patient’s symptoms and a further improvement in the number of any blood cell lines chiefly platelet which is one of the regulators of the coagulation pathway, and its deficiency increase the risk of bleeding.