[¹⁸F-FDG PET-CT in cytomegalovirus-induced mononucleosis]

The case of a 51 years-old woman with high fever, asthenia and weight loss of three weeks of evolution is presented. She had a personal history of breast cancer and liver metastases. The physical examination showed small painless enlarged lymph nodes in both latero-cervical chains. The blood analysis showed 9200 leukocytes with 69% of lymphocytes and elevated liver enzymes. Serological determinations as well as repeated blood and urine culture were negatives, only the anti-CMV IgM determination being positive. The CEA tumor marker was slightly elevated. PET/CT demonstrated hypermetabolic enlarged lymph nodes in the bilateral cervical chains and in celiac region, hepatosplenomegaly and diffusely increased ¹⁸F-FDG uptake in the spleen. These alterations were associated with CMV infection. Her evolution was favorable, and she was diagnosed of CMV mononucleosis. The appropriate clinical and immunological diagnosis of IM in patients aged over 40 years is important to avoid unnecessary diagnostic procedures.