Evalution of jak2 mutation presence in children thinked for primary thrombocytosis

Thrombocytosis is divided into two as primary and secondary (reactive). Primary thrombocytosis is a myeloproliferative disease caused by monoclonal or polyclonal abnormalities of hematopoietic stem cells or abnormalities in TPO biology. Our aim in this study is to determine the frequency of JAK2 mutation in children with primary thrombocytosis. The families of 150 children who applied to Adnan Menderes University Faculty of Medicine Child Health and Diseases Policlinic between 01 January 2017 and 31 July 2018 and whose platelet counts >500.000/μL were called by phone and were called for control evaluation. Fifty children were not brought by their families for control evaluation. Fifty children were excluded from the study because the number of platelets was normal, 20 children were diagnosed with iron deficiency anemia and 9 children were considered thrombocytosis secondary to infection or inflammation. Thirteen male (%61.9) and 21 cases with primary thrombocytosis were included in the study. Hemogram, ESR, CRP, fibrinogen and ferritin levels, serum iron and total serum iron binding capacities were examined. The JAK2 V617F mutation analysis was performed with the Real Time-PCR method by testing with the "Ipsogen® JAK2 RGQ PCR Kit" (Qiagen, Germany). The mean age of the patients was 6,76±2,94 years (range 3-13 years). There were no findings suggesting myeloproliferative disease in history, physical examination, hemogram and peripheral blood smear examination. Average ferritin level 28,38±11,48 ng/mL, serum iron level 67,52±22,62 μg/dL, serum iron binding capacity 269,4±52,26 μg/dL, fibrinogen level was 288,0±43,40 mg/dL. CRP was negative and ESR was normal in all patients. The mean hemoglobin level of the patients was 12,28±0,95 g/dL, the mean number of leukocytes was 9,120±950/μL, the average number of platelets was 613,000±96,820/μL (range 504-830,000/μL). The JAK2 V617F mutation was not detected in any patient. We think that it is not necessary to look for a JAK2 mutation in children with primary thrombocytosis without a history, physical examination and / or complete blood count and peripheral blood smear findings suggesting myeloproliferative disease.