In recent years, anti-CD20 antibodies have been increasingly used to treat lymphoproliferative and immune disorders. Chronic viral infections are infrequently reported in patients receiving these therapies. Enteroviral infection can cause life-threatening meningoencephalitis and other systemic chronic syndromes in immune deficient patients. We describe the clinical courses and outcomes of 6 patients from 2 tertiary care institutions who developed chronic enteroviral infection with neurological manifestations, after combined chemoimmunotherapy with rituximab for B-cell lymphoma. We review the literature that includes 10 sporadic reported cases of chronic enteroviral meningoencephalitis attributed to rituximab therapy. It is a rare disease, and its diagnosis is often elusive. We propose that low immunoglobulin G levels are the main risk factor for developing chronic enteroviral infection and emphasize the need for a high index of suspicion, early diagnosis, and intervention in this iatrogenic and potentially fatal complication.