The existence of extrahepatic replication sites of hepatitis C virus (HCV) remains controversial. Highly strand-specific Tth-based reverse transcriptase-polymerase chain reaction was used to search for the presence of viral RNA negative strand in lymph nodes from 16 patients with AIDS and in peripheral blood mononuclear cells (PBMC) from 14 other human immunodeficiency virus (HIV)-positive patients. Negative-strand HCV RNA was detected in lymph node samples from 10 patients (63%) and in PBMC from 5 (36%). This suggests that, at least under circumstances of impaired immunity associated with HIV infection, HCV is lymphotropic in vivo. However, the clinical implications of these findings need to be further investigated.