Graves' hyperthyroidism-related pancytopenia: a case report with literature review

Occurrence of pancytopenia in patients with untreated hyperthyroidism is extremely rare. To the best of our knowledge, only 30 cases have been reported in the English literature. Accurate diagnosis and appropriate tailored therapy are challenging due to the variegated causes of pancytopenia and the potential hematological toxicity of antithyroid drugs (ATDs).

We present a 51-year-old Caucasian man with newly diagnosed Graves' disease showing pancytopenia and liver dysfunction. Although in this context the use of ATDs is still under debate, low-dose methimazole therapy was able to induce resolution of both pancytopenia and liver dysfunction, along with euthyroidism restoration.

Searching in the English literature for previous studies, we identified only 30 cases worldwide to form our database. A demographic as well as clinical, laboratory, and histopathological analysis was performed. In most cases, the recovery of biochemical euthyroidism through the use of ATDs induced the resolution of pancytopenia (at laboratory and histological levels). Our review provides clinical, laboratory, and histopathological features of Graves's hyperthyroidism-related pancytopenia with a view to improving the knowledge of this rare hematological complication and assisting in the decision-making process regarding therapeutic options.