title: Alveolar and blood T lymphocyte profiles in Pneumocystis jirovecii-positive patients: effects of HIV status.
abstract: BACKGROUND
  There are substantial differences in the risk evaluation, clinical presentation, and outcome of Pneumocystis pneumonia between human immunodeficiency virus (HIV)-positive and HIV-negative immunocompromised patients. To compare the host immune defenses against Pneumocystis jirovecii, the blood and alveolar lymphocyte profile was explored in these 2 populations.
  
  
  METHODS
  The total, CD3(+), CD4(+), and CD8(+) T-lymphocyte counts were measured in the blood and alveoli of immunocompromised patients with a P. jirovecii DNA detected in their bronchoalveolar lavage samples, according to their HIV status.
  
  
  RESULTS
  In blood and alveoli, the CD4(+) and CD8(+) T-lymphocyte counts were higher and lower, respectively, in the HIV-negative group. The threshold for initiating prophylaxis in HIV-positive persons, 200 CD4(+) T cells/μL, was not pertinent for HIV-negative patients. The P. jirovecii burden correlated with the blood CD4(+) T-cell counts in the HIV-positive but not in the HIV-negative group. Nevertheless, whatever the HIV status, a correlation was observed between alveolar CD4(+) T cells and the P. jirovecii burden.
  
  
  CONCLUSIONS
  The T-lymphocyte profile was different between HIV-positive and HIV-negative patients with P. jirovecii, suggesting a distinct pathogenesis. Alveolar CD4(+) T cells could be critical to explain the development of Pneumocystis pneumonia but may also be important for evaluation of disease risk, mostly among HIV-negative immunocompromised patients.
authors.affiliation: Service de Parasitologie-Mycologie, Centre Hospitalier Universitaire de Toulouse and Faculté de Médecine de Rangueil, France. xabierlete@yahoo.fr
authors.forename: Xavier
authors.initials: X
authors.lastname: Iriart
authors.forename: Benoit
authors.initials: B
authors.lastname: Witkowski
authors.forename: Sophie
authors.initials: S
authors.lastname: Cassaing
authors.forename: Sarah
authors.initials: S
authors.lastname: Abbes
authors.forename: Sandie
authors.initials: S
authors.lastname: Menard
authors.forename: Judith
authors.initials: J
authors.lastname: Fillaux
authors.forename: Alexis
authors.initials: A
authors.lastname: Valentin
authors.forename: Marie-Denise
authors.initials: MD
authors.lastname: Linas
authors.forename: Jean
authors.initials: J
authors.lastname: Tkaczuk
authors.forename: Françoise
authors.initials: F
authors.lastname: Huget
authors.forename: Anne
authors.initials: A
authors.lastname: Huynh
authors.forename: Christophe
authors.initials: C
authors.lastname: Hermant
authors.forename: Roger
authors.initials: R
authors.lastname: Escamilla
authors.forename: Nassim
authors.initials: N
authors.lastname: Kamar
authors.forename: Olivier
authors.initials: O
authors.lastname: Cointault
authors.forename: Laurence
authors.initials: L
authors.lastname: Lavayssiere
authors.forename: Muriel
authors.initials: M
authors.lastname: Alvarez
authors.forename: Antoine
authors.initials: A
authors.lastname: Blancher
authors.forename: Bruno
authors.initials: B
authors.lastname: Marchou
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Magnaval
authors.forename: Antoine
authors.initials: A
authors.lastname: Berry
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D015658:HIV Infections / Q000097:blood* / Q000150:complications* / Q000382:microbiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D045363:Pneumocystis carinii / Q000302:isolation & purification*; D011020:Pneumonia, Pneumocystis / Q000276:immunology*; D011650:Pulmonary Alveoli / Q000166:cytology*; D016176:T-Lymphocyte Subsets / Q000502:physiology*