title: Severe 2009 pandemic influenza A (H1N1) infection and increased mortality in patients with late and advanced HIV disease.
abstract: OBJECTIVE
  To describe the clinical course of infection by 2009 (H1N1) influenza virus in different stages of HIV disease.
  
  
  METHODS
  Prospective, observational study.
  
  
  METHODS
  During the pandemic period, HIV-infected patients presenting respiratory symptoms at a third level referral hospital in Mexico City were tested for 2009 influenza A (H1N1) viral RNA. Clinical files were prospectively analyzed.
  
  
  RESULTS
  Infection by H1N1 was confirmed in 30 (23.8%) of the total 126 HIV-infected patients studied. In the group of patients with 2009 H1N1 virus infection, 16 (53.3%) were hospitalized, 12 (40%) had active opportunistic infections and six (20%) died. In the group of 96 patients not infected with 2009 H1N1 virus, 54 (56.25%) were hospitalized with opportunistic infections and 12 (12.5%) died. For all hospitalized patients, being on HAART and having undetectable HIV viral loads at hospitalization was associated with higher survival (P = 0.019). Patients with 2009 H1N1 virus infection had a higher mortality rate, even after adjusting for HAART (P = 0.043). Coinfection by HIV and H1N1 2009 virus was more severe in patients with opportunistic infections, as shown by longer hospital stays (P = 0.0013), higher rates of hospitalization (P < 0.0001), use of mechanical ventilation (P = 0.0086) and death (P = 0.026). Delayed administration of oseltamivir in hospitalized patients was significantly associated with mortality (P = 0.0022).
  
  
  CONCLUSIONS
  Our data suggest that infection by 2009 H1N1 is more severe in HIV-infected patients with late and advanced HIV disease than in well controlled patients under HAART.
authors.affiliation: Center for Research in Infectious Diseases, National Institute of Respiratory Diseases, Mexico City, Mexico.
authors.forename: Christopher E
authors.initials: CE
authors.lastname: Ormsby
authors.forename: Daniela
authors.initials: D
authors.lastname: de la Rosa-Zamboni
authors.forename: Joel
authors.initials: J
authors.lastname: Vázquez-Pérez
authors.forename: Yuria
authors.initials: Y
authors.lastname: Ablanedo-Terrazas
authors.forename: Ricardo
authors.initials: R
authors.lastname: Vega-Barrientos
authors.forename: María
authors.initials: M
authors.lastname: Gómez-Palacio
authors.forename: Akio
authors.initials: A
authors.lastname: Murakami-Ogasawara
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Ibarra-Ávalos
authors.forename: Dámaris
authors.initials: D
authors.lastname: Romero-Rodríguez
authors.forename: Santiago
authors.initials: S
authors.lastname: Avila-Ríos
authors.forename: Gustavo
authors.initials: G
authors.lastname: Reyes-Terán
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000276:immunology* / Q000401:mortality / Q000821:virology; D023241:Antiretroviral Therapy, Highly Active; D024921:Drug Resistance, Multiple, Viral; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000401:mortality*; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification*; D007251:Influenza, Human / Q000150:complications* / Q000401:mortality / Q000821:virology; D008297:Male; D008800:Mexico / Q000453:epidemiology; D009297:Nasal Mucosa / Q000821:virology; D058873:Pandemics; D011446:Prospective Studies