Proceedings of the International scientific and practical conference ―Modern Science: Challenges and Perspectives‖ (February 9-11, 2026) / Publisher website: www.naukainfo.com. - London, United Kingdom, 2026. - 121 p.

107 The patients received treatment with valacyclovir 1000 mg three times daily for 21 days, followed by a switch to suppressive dosing of 500 mg three times daily for one month. She was discharged under the supervision of a pediatrician and an infectious disease specialist. Every three months, the child undergoes follow-up examinations by a pediatrician with monitoring of EBV markers and ultrasound assessment of the lymph nodes to determine the need for further imaging studies (PET-CT) and the necessity of a repeat control biopsy. The girl is growing and developing according to her age. Lymph node ultrasound one month after completion of antiviral therapy revealed: submandibular and posterior cervical lymph nodes measuring 10–15 mm in diameter, hypoechoic, with minimal vascularity; supraclavicular and infraclavicular lymph nodes measuring 12–15 mm; mediastinal lymph nodes measuring 10–12 mm; right and left axillary lymph nodes measuring 10–12 mm; and bilateral inguinal lymph nodes measuring 10–12 mm in diameter, hypoechoic, with minimal vascularity. Discussion. EBV-associated lymphoproliferative processes may occur as de novo infection, reactivation, and/or malignant transformation [3]. This pattern was observed in our patient (reactivation of EBV infection over the subsequent two years after the primary episode, with relapses at 1, 7, and 11 months), accompanied by subfebrile temperature, increased fatigue, and enlargement of anterior and posterior cervical lymph nodes. These episodes were confirmed by serological and virological markers—anti-VCA IgM, EA IgG, anti-EBNA IgG, and viral DNA detected in saliva. The recurrent episodes suggest EBV persistence in the patient as the underlying cause of the lymphoproliferative process, which was also supported by immunohistochemical findings (reactive hyperplasia with signs of expressed immune blast transformation in the lymphoid follicles and the presence of occasional CD30- positive cells, possibly activated B lymphocytes). The discrepancies between the histological and immunohistochemical findings can be explained. The diagnosis of Hodgkin lymphoma is based on the identification of large lymphoid cells with hyperchromatic nuclei, indicating atypical cells characteristic of this pathology. Hodgkin lymphoma may present with diverse