Tuberc Respir Dis.  2010 Aug;69(2):103-107.

Initial Chest CT Findings of 2009 H1N1 Influenza Pneumonia in Helping Predict Clinical Outcomes

• Ryoo SM
• Kim WY
• Lee CW
• Sohn CH
• Seo DW
• Lee YS
• Lee JH
• Oh BJ
• Kim W
• Lim KS

Abstract

BACKGROUND
The aim of the present study was to evaluate whether findings on initial chest computed tomography (CT) of influenza pneumonia can help predict clinical outcome.
METHODS
We reviewed all adult patients admitted to the Emergency Department (ED) with a confirmed diagnosis of novel influenza A H1N1 virus (2009 H1N1) pneumonia, who underwent chest CT upon admission between Aug 26, 2009 and Jan 31, 2010. Radiologic findings were characterized by type and pattern of opacities and zonal distribution. Clinical outcome measures were intensive care unit (ICU) admission, mechanical ventilation, and inhospital death.
RESULTS
Of 59 patients diagnosed with 2009 H1N1 pneumonia, 41 (69.5%) underwent chest CT on admission into ED. Nine (22%) of these patients developed adverse clinical outcomes requiring the following treatments: 9 (22.0%) ICU admissions, 5 (12.2%) mechanical ventilation, and 3 (7.3%) inhospital deaths. Counting the number of patients with more than 4 involved lobes, the sensitivity, specificity, positive predictive value, and negative predictive value for detection of adverse clinical outcome were 67%, 84%, 55% and 80%, respectively.
CONCLUSION
Extensive involvement of both lungs (over 4 lobes) is related to ICU admission, mechanical ventilation, and inhospital death. Initial chest CT may help predict an adverse clinical outcome of patients with 2009 H1N1 influenza pneumonia.

Keyword

Influenza A Virus, H1N1 Subtype; Tomography, X-Ray Computed; Respiration, Artificial; Mortality

MeSH Terms

Adult
Emergencies
Fluconazole
Humans
Influenza A Virus, H1N1 Subtype
Influenza, Human
Intensive Care Units
Lung
Outcome Assessment (Health Care)
Pneumonia
Respiration, Artificial
Thorax
Tomography, X-Ray Computed
Fluconazole

Figure

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  Figure 1 Receiver operating characteristic (ROC) curve for numbers of involved lobe.

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