Biomarkers and bacterial pneumonia risk in patients with treated HIV infection: a case-control study

PLoS One. 2013;8(2):e56249. doi: 10.1371/journal.pone.0056249. Epub 2013 Feb 15.

Abstract

Background: Despite advances in HIV treatment, bacterial pneumonia continues to cause considerable morbidity and mortality in patients with HIV infection. Studies of biomarker associations with bacterial pneumonia risk in treated HIV-infected patients do not currently exist.

Methods: We performed a nested, matched, case-control study among participants randomized to continuous combination antiretroviral therapy (cART) in the Strategies for Management of Antiretroviral Therapy trial. Patients who developed bacterial pneumonia (cases) and patients without bacterial pneumonia (controls) were matched 1∶1 on clinical center, smoking status, age, and baseline cART use. Baseline levels of Club Cell Secretory Protein 16 (CC16), Surfactant Protein D (SP-D), C-reactive protein (hsCRP), interleukin-6 (IL-6), and d-dimer were compared between cases and controls.

Results: Cases (n = 72) and controls (n = 72) were 25.7% female, 51.4% black, 65.3% current smokers, 9.7% diabetic, 36.1% co-infected with Hepatitis B/C, and 75.0% were on cART at baseline. Median (IQR) age was 45 (41, 51) years with CD4+ count of 553 (436, 690) cells/mm(3). Baseline CC16 and SP-D were similar between cases and controls, but hsCRP was significantly higher in cases than controls (2.94 µg/mL in cases vs. 1.93 µg/mL in controls; p = 0.02). IL-6 and d-dimer levels were also higher in cases compared to controls, though differences were not statistically significant (p-value 0.06 and 0.10, respectively).

Conclusions: In patients with cART-treated HIV infection, higher levels of systemic inflammatory markers were associated with increased bacterial pneumonia risk, while two pulmonary-specific inflammatory biomarkers, CC16 and SP-D, were not associated with bacterial pneumonia risk.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anti-HIV Agents / therapeutic use*
  • Biomarkers / blood*
  • C-Reactive Protein
  • Case-Control Studies
  • Female
  • Fibrin Fibrinogen Degradation Products
  • HIV Infections / blood*
  • HIV Infections / complications*
  • HIV Infections / drug therapy
  • Humans
  • Interleukin-6 / blood
  • Lung / virology
  • Male
  • Middle Aged
  • Pneumonia, Bacterial / blood*
  • Pneumonia, Bacterial / diagnosis
  • Pneumonia, Bacterial / etiology*
  • Pneumonia, Bacterial / virology
  • Pulmonary Surfactant-Associated Protein D / blood
  • Risk Factors
  • Uteroglobin / blood

Substances

  • Anti-HIV Agents
  • Biomarkers
  • Fibrin Fibrinogen Degradation Products
  • Interleukin-6
  • Pulmonary Surfactant-Associated Protein D
  • SCGB1A1 protein, human
  • fibrin fragment D
  • C-Reactive Protein
  • Uteroglobin