title: [Idiopathic CD4+ lymphocytopenia: a case report].
abstract: We present the case of a 47-year-old patient who was seen for recurrent opportunistic infections. Immunophenotypic analyses disclosed severe reduction of CD4+ T cells. Repeated Elisa, Western blot and polymerase chain reaction tests for HIV were negative. The low CD4+ T lymphocyte count unaccompanied by increased CD8+ T lymphocytes and hypergammaglobulinemia, along with negativity for HIV infection, suggested the diagnosis of idiopathic CD4+ lymphocytopenia (ICL). The patient's clinical manifestations and laboratory results conformed with the case definition of ICL established in 1992 by the Centers for Disease Control of Atlanta, i.e., CD4+ T cells < 300/mm3 on two occasions and no evidence of HIV infection. In vitro analyses evidenced depressed lymphoproliferative responses to mitogens such as concanavalin A and pokeweed mitogen, while the expression of Fas antigen on peripheral lymphocytes and the percentage of apoptotic cells after propidium iodide staining were increased. Since in vitro concanavalin A stimulation inhibits T cell proliferation and induces apoptosis, these results suggest that the patient's lymphocytes are susceptible, in vivo, to an apoptotic signal.
authors.affiliation: Dipartimento di Scienze Biomediche ed Oncologia Umana, Università degli Studi di Bari.
authors.forename: M A
authors.initials: MA
authors.lastname: Frassanito
authors.forename: G
authors.initials: G
authors.lastname: Iodice
authors.forename: R
authors.initials: R
authors.lastname: Rizzi
authors.forename: F
authors.initials: F
authors.lastname: Dammacco
mesh_terms: D017209:Apoptosis; D001996:Bronchopneumonia / Q000097:blood / Q000175:diagnosis; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000473:pathology; D002180:Candidiasis, Oral / Q000097:blood / Q000175:diagnosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009894:Opportunistic Infections / Q000097:blood / Q000175:diagnosis; D012008:Recurrence; D018344:T-Lymphocytopenia, Idiopathic CD4-Positive / Q000097:blood / Q000175:diagnosis*
vernacular_title: Linfocitopenia CD4+ idiopatica: descrizione di un caso.