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URL of this page: //medlineplus.gov/ency/imagepages/2275.htm

Mononucleosis - photomicrograph of cell

Mononucleosis - photomicrograph of cell

Overview

This picture shows large, atypical lymphocytes (white blood cells). These cells are seen in viral infections, most commonly caused by the Epstein-Barr virus (infectious mononucleosis), cytomegalovirus diseases, and occasionally infectious hepatitis. This is an example of a type I Downy cell.

Review Date 3/16/2024

Updated by: Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.