Thirty-one (31%) patients were immunocompromised: 12 with neoplasms (diagnosed during the last year), six with cirrhosis, six HIV-infected (two with CD4 T-cells under 200/mm3), three splenectomized patients, three with immunosuppressor drugs and 1 chronic renal insufficiency undergoing dialysis. The gene discussed is CD4; the disease is neoplasm.