title: Pneumocystis pneumonia in patients with inflammatory or autoimmune diseases: Usefulness of lymphocyte subtyping.
abstract: OBJECTIVE
  No consensus currently exists on the indications for Pneumocystis jirovecii prophylaxis in patients with inflammatory or autoimmune diseases. The main objective was to identify biomarkers associated with P. jirovecii pneumonia (PCP) in this population.
  
  
  METHODS
  A retrospective study was carried out at Beijing Union Medical College Hospital (2003-2014). All patients with an inflammatory or autoimmune disease presenting with acute onset of fever and respiratory symptoms were included.
  
  
  RESULTS
  A total of 123 patients were included, of whom 42% had confirmed PCP, 18% had possible PCP, and 40% were negative for PCP. Immunosuppressive conditions consisted mostly of diffuse connective tissue disease (50%) and primary nephropathy (20%). Immunosuppressive therapies consisted of corticosteroids (95%) with concomitant non-steroidal drugs (80%). Independent predictors of PCP were a CD3+ cell count <625×106/l, serum albumin <28g/l, and PaO2/FiO2<210. Furthermore, 90% of patients with PCP had a CD3+ cell count <750×106/l. Independent predictors of mortality were a CD8+ cell count <160×106/l and a PaO2/FiO2<160.
  
  
  CONCLUSIONS
  In patients with inflammatory and autoimmune conditions receiving immunosuppressive therapy, low CD3+ and CD8+ cell counts were strongly associated with PCP and its mortality. These results suggest that lymphocyte subtyping is a very useful tool to optimize the selection of patients needing prophylaxis.
authors.affiliation: Emergency Department, Peking Union Medical College Hospital, Beijing, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.affiliation: Nephrology Department, Verdun Hospital, University of Montreal, Montreal, QC, Canada.
authors.forename: Marc
authors.initials: M
authors.lastname: Ghannoum
authors.affiliation: Emergency Department, Shenzhen Luohu People's Hospital, Shenzhen, China.
authors.forename: Chuntao
authors.initials: C
authors.lastname: Deng
authors.affiliation: Emergency Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Emergency Department, Peking Union Medical College Hospital, Beijing, China.
authors.forename: Huadong
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Emergency Department, Peking Union Medical College Hospital, Beijing, China.
authors.forename: Xuezhong
authors.initials: X
authors.lastname: Yu
authors.affiliation: Medical Microbiology and Infectious Diseases Department, Sacré-Cœur Hospital, University of Montreal, 5400 Boulevard Gouin Ouest, Montreal, QC, H2V 3A5, Canada. Electronic address: valerylavergne@gmail.com.
authors.forename: Valery
authors.initials: V
authors.lastname: Lavergne
mesh_terms: D000328:Adult; D001327:Autoimmune Diseases / Q000150:complications* / Q000188:drug therapy / Q000276:immunology; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007249:Inflammation / Q000150:complications* / Q000188:drug therapy / Q000276:immunology; D016131:Lymphocyte Subsets / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011020:Pneumonia, Pneumocystis / Q000209:etiology* / Q000517:prevention & control; D012189:Retrospective Studies
chemical_list: D007166:Immunosuppressive Agents
keywords: Autoimmune disease; CD3+ cell; CD8+ cell; Inflammatory disease; Lymphocyte subtype; Pneumocystis jirovecii