The syndrome of inflammatory subacute lumbosacral polyradiculoneuropathy (SLP) has been reported in acquired immunodeficiency syndrome (AIDS) patients in association with cytomegalovirus infection and is only partially amenable to anti-viral therapy. We report three cases of relatively benign inflammatory painful SLP in two non-AIDS, immunosuppressed patients and one who HIV-seroconversed at the time of clinical presentation. SLP developed: (1) in association with HIV seroconversion; (2) during ECHO virus infection in a patient with common variable immune deficiency; and (3) after a severe systemic infection that induced transient immunosuppression due to Epstein-Barr virus reactivation. This report expands the spectrum of viruses associated with acute and subacute lumbosacral polyradiculoneuropathy and may shed light on its possible pathogenesis.