A New Pulmonary Nodule in a Patient With a History of Lymphoma.

A 70-year-old woman who formerly used tobacco was referred for evaluation of a lung nodule incidentally discovered during hematologic follow-up. Her medical history was notable for a stage IV follicular lymphoma (G2/G3A stage IV, for pleural and perinephric involvement, FLIPI4) in September 2022, for which she received 6 courses of obinutuzumab plus bendamustine. After the second cycle of therapy, an increase in transaminases was detected; the subsequent diagnostic workup showed a positive real-time polymerase chain reaction blood test for human herpesvirus 6 DNA with more than 13,000 copies/mL. The human herpesvirus 6 infection was successfully treated with acyclovir, followed by normalization of liver enzymes. The treatment was then completed regularly, obtaining a complete metabolic response. One month after completing therapy, the patient developed systemic cytomegalovirus infection with associated pneumonia, requiring 3 weeks of hospitalization. Considering the severity of the infectious event, a further maintenance with obinutuzumab was excluded. Persistent cytomegalovirus-DNA levels necessitated valganciclovir. Sustained neutropenia partially improved with granulocyte colony-stimulating factor administration.