Idiopathic Thrombocytosis in Alpha Thalassemia Trait Patient.

Platelet count increases are typically a reactionary response to one of a variety of pathophysiological events. We present here a case of microcytic hypochromic red blood cells and thrombocytosis in an adolescent female that we have monitored for three years. The patient was positive for alpha thalassemia trait; negative for mutation in Janus kinase 2, calreticulin, or myeloproliferative leukemia virus oncogene; and negative for reactive causes of thrombocytosis. Noticeably, a variant in atypical chemokine receptor 1 (ACKR1) (c.-67T>C, rs2814778) was found to be homozygous. Accordingly, the case was diagnosed as idiopathic thrombocytosis, and treatment was given to restore platelet levels to normal. Our findings highlight the possibility of an unknown association between alpha thalassemia trait and idiopathic thrombocytosis in the presence of ACKR1 mutation, which could be implicated in disease pathogenesis.