Ventilator-Associated Pneumonia: Diagnostic Test Stewardship and Relevance of Culturing Practices

  • Blaine KenaaEmail author
  • Mary Elizabeth Richert
  • Kimberly C. Claeys
  • Andrea Shipper
  • Kaede V. Sullivan
  • Gregory M. Schrank
  • Lyndsay M. O’Hara
  • Daniel J. Morgan
  • Carl Shanholtz
  • Surbhi Leekha
Healthcare Associated Infections (G Bearman and D Morgan, Section Editors)
Part of the following topical collections:
  1. Topical Collection on Healthcare Associated Infections


Purpose of Review

Ventilator-associated pneumonia (VAP) is one of the most common infections in the ICU. Prompt diagnosis is vital as mortality increases with delayed antibiotic therapy. However, accurate diagnosis is challenging due to non-specific clinical features in a complicated patient cohort. Microbiological culture data remains a crucial aspect in confirming diagnosis.

Recent Findings

Literature data comparing the benefit of invasive respiratory sampling to non-invasive is inconclusive. Differences in culturing practices translate in overidentification of organisms of unclear significance. Positive culture data in a low pre-test probability does not differentiate between true infection and colonization resulting in overtreatment. Furthermore, there are also opportunities for modifying the reporting of respiratory tract cultures that can better guide antimicrobial therapy.


Under the umbrella of antimicrobial stewardship, diagnostic stewardship can be incorporated to create a systematic approach that would target culturing practices to match the right pre-test probability. Ideal outcome will be targeting cultures to the right patient population and minimizing unnecessary treatment.


Ventilator-associated pneumonia Diagnostic stewardship Antimicrobial stewardship Selective culture reporting Invasive respiratory culturing Endotracheal aspirate 


Compliance with Ethical Standards

Conflict of Interest

Dr. Kenaa declares that she has nothing to disclose.

Dr. Richert declares that she has nothing to disclose.

Dr. Claeys reports personal fees from Luminex Corporation, other from BioFire Diagnostics, from GenMark Diagnostics, outside the submitted work.

Ms. Shipper declares that she nothing to disclose.

Dr. O’Hara declares that she has nothing to disclose.

Dr. Sullivan declares that he has nothing to disclose.

Dr. Schrank declares that he has nothing to disclose.

Dr. Morgan reports grants from CDC, NIH, AHRQ, grants from VA HSRD, other from IDSA and SHEA for expenses to organize or present at national meetings, other from Springer Nature Inc., outside the submitted work.

Dr. Shanholtz declares that he has nothing to disclose.

Dr. Leekha reports grants from CDC and AHRQ, outside the submitted work.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Blaine Kenaa
    • 1
    Email author
  • Mary Elizabeth Richert
    • 2
  • Kimberly C. Claeys
    • 3
  • Andrea Shipper
    • 4
  • Kaede V. Sullivan
    • 5
  • Gregory M. Schrank
    • 6
  • Lyndsay M. O’Hara
    • 7
  • Daniel J. Morgan
    • 7
  • Carl Shanholtz
    • 1
  • Surbhi Leekha
    • 7
  1. 1.Department of Medicine, Department of Pulmonary and Critical CareUniversity of Maryland School of MedicineBaltimoreUSA
  2. 2.Division of Internal Medicine, PGY-3, Department of Medicine, University of Maryland School of MedicineUniversity of Maryland Medical CenterBaltimoreUSA
  3. 3.Infectious Diseases, Department of Pharmacy Practice and ScienceUniversity of Maryland School of PharmacyBaltimoreUSA
  4. 4.Health Sciences and Human Services LibraryUniversity of Maryland BaltimoreBaltimoreUSA
  5. 5.Pathology and Laboratory Medicine, Medicine Education and Research BuildingLewis Katz School of MedicinePhiladelphiaUSA
  6. 6.Division of Infectious Diseases, Department of Medicine, University of Maryland School of MedicineUniversity of Maryland Medical CenterBaltimoreUSA
  7. 7.Department of Epidemiology and Public HealthUniversity of Maryland School of MedicineBaltimoreUSA

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