Cyclic thrombocytopenia diagnosed by periodic platelet count measurements

Abstract

Cyclic thrombocytopenia (CTP) is characterized by periodic platelet count fluctuations and is commonly misdiagnosed as immune thrombocytopenia (ITP) because of their similar clinical characteristics. Here, we present the case of a 74-year-old man with CTP diagnosed by weekly platelet count measurements. The patient initially developed mild bleeding symptoms with a platelet count of 0.8×10⁴/µl. Bone marrow biopsy exhibited reduced megakaryocyte counts, an atypical characteristic of ITP. Weekly follow-up of platelet counts demonstrated an apparent cyclic pattern, resulting in CTP diagnosis. Regular platelet count measurements can help diagnose CTP in thrombocytopenia.