Polycythemia in childhood: diagnostic challenges

Polycythemia is an increase in hemoglobin/hematocrit levels, indicating several conditions that lead to elevated red blood cell production. It’s crucial to identify true polycythemia vera (PV), which needs targeted treatment to manage blood cell production and prevent complications like thrombosis. Secondary polycythemia (SP) requires identifying and addressing the underlying cause to normalize blood counts. Each type has distinct causes and mechanisms that guide treatment and complication prevention. Aim - to analyse the clinical features of polycythemia and approaches to its diagnosis in children on the basis of clinical cases. Clinical cases of children with polycythemia were analyzed alongside a literature review. Diagnostic methods included blood count, cytological and pathological examinations, molecular genetic testing (in two labs), as well as imaging techniques like ultrasound, electrocardiography, echocardiography, radiography, computed tomography, and fibrogastroduodenoscopy, colonoscopy. Four clinical cases of polycythemia are described: SP in a 14-year-old girl with a congenital heart defect and pulmonary hypertension, showing chronic hypoxia and hypoxemia; іdiopathic рolycythemia (IP) in a 16-year-old boy who smokes; PV in two children with the JAK2 V617F mutation: a 16-year-old girl with coagulogram changes, facial and hand hyperemia, and a 17-year-old boy with splenomegaly. The focus is on the similarities and differences in clinical and laboratory features of these polycythemia types in children, highlighting the need for additional studies, including genetic testing, for accurate diagnosis. Conclusions. Discrepancies in the clinical and laboratory presentation of different types of polycythemia emphasize the need for an integrated approach to diagnosis for disease’s timely detection, prescription of effective treatment and prevention of complications. The research was carried out in accordance with the principles of the Helsinki Declaration. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.