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Can procalcitonin tests aid in identifying bacterial infections associated with influenza pneumonia? A systematic

Meng-Huan Wu1, Chi-Chun Lin, Shiau-Ling Huang

  • 1Department of Emergency Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan.

Influenza and Other Respiratory Viruses
|June 8, 2012
PubMed
Abstract

Insights

Procalcitonin (PCT) tests show high sensitivity but low specificity for bacterial infections in influenza patients. PCT is a useful rule-out test but not a standalone rule-in diagnostic tool.

Area of Science:

  • Infectious Diseases
  • Clinical Diagnostics
  • Biomarkers

Background:

  • Secondary bacterial infections complicate influenza, necessitating accurate diagnostic tools.
  • Procalcitonin (PCT) is investigated as a biomarker for bacterial infections.

Purpose of the Study:

  • To evaluate the diagnostic accuracy of procalcitonin (PCT) tests.
  • To identify secondary bacterial infections in patients with influenza.

Main Methods:

  • Systematic review of studies published between 1966 and 2009.
  • Inclusion of studies evaluating PCT for bacterial infections in influenza patients.
  • Data extraction for two-by-two table construction.

Main Results:

  • Six studies with 137 bacterial coinfection cases and 381 controls were analyzed.
  • Overall sensitivity: 0.84 (95% CI: 0.75-0.90); Specificity: 0.64 (95% CI: 0.58-0.69).
  • Area under ROC curve: 0.68. Positive Likelihood Ratio (LR+): 2.31; Negative Likelihood Ratio (LR-): 0.26.

Conclusions:

  • Procalcitonin tests demonstrate high sensitivity, especially in ICU patients, but low specificity for bacterial infections in influenza.
  • PCT serves as a valuable rule-out test due to its low negative likelihood ratio.
  • PCT is not recommended as a standalone rule-in diagnostic test due to its suboptimal positive likelihood ratio.

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