SummaryNo specific symptomatology can be ascribed to the lymphadenopathic form of the acquired toxoplasmosis, which may run a subclinical course or evoke severe diseases, such as infectious mononucleosis or Hodgkin's disease.The physician and even the pathologist, when confronted with a case of adenopathies of obscure aetiology, may miss the true diagnosis if they do not look for a toxoplasmic infection. Pathological examination of lymph nodes is not always conclusive. Serologic tests and inoculation of lymph node material into mice afford a definitive diagnosis.The two clinical cases reported above suggest that toxoplasmosis should be more frequently thought of as a cause of adenopathy in the adult.