Korean J Intern Med.  2011 Jun;26(2):160-167. 10.3904/kjim.2011.26.2.160.

Outcome of Pandemic H1N1 Pneumonia: Clinical and Radiological Findings for Severity Assessment

• Cho WH
• Kim YS
• Jeon DS
• Kim JE
• Kim KI
• Seol HY
• Kim KU
• Park HK
• Lee MK
• Park SK
• Jeong YJ

• KMID: 1776588
• DOI: http://doi.org/10.3904/kjim.2011.26.2.160

Abstract

BACKGROUND/AIMS
Pandemic influenza A (H1N1) virus infection presents with variable severity. However, little is known about clinical predictors of disease severity. We studied the clinical predictors of severe pandemic H1N1 pneumonia and their correlation with radiological findings.
METHODS
We reviewed medical and radiological records of adults with pandemic H1N1 pneumonia. After classification of patients into severe and non-severe groups, the following data were evaluated: demographic data, pneumonia severity index (PSI), CURB65, risk factors, time to first dose of antiviral medication, routine laboratory data, clinical outcome, and radiological characteristics.
RESULTS
Of 37 patients with pandemic H1N1 pneumonia, 12 and 25 were assigned to the severe and non-severe groups, respectively. PSI score, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dyhydrogenase (LDH) levels were higher in the severe group than in the non-severe group (p = 0.035, 0.0003, 0.0023, and 0.0002, respectively). AST, ALT, and LDH levels were positively correlated with the radiological findings (p < 0.0001, 0.0003, and < 0.0001, respectively) and with the number of involved lobes (p = 0.663, 0.0134, and 0.0019, respectively). The most common finding on high resolution computed tomography (HRCT) scans was ground-glass attenuation with consolidation (n = 22, 60%), which had a predominantly patchy distribution (n = 31).
CONCLUSIONS
We demonstrated a positive correlation between clinical findings, such as serum AST, ALT, and LDH levels, and radiological findings. A combination of clinical and HRCT indicators would be useful in predicting the clinical outcome of pandemic H1N1 pneumonia.

Keyword

Influenza A virus, H1N1 subtype; Pneumonia; Severity of illness index

MeSH Terms

Adolescent
Adult
Aged
Alanine Transaminase/blood
Antiviral Agents/therapeutic use
Aspartate Aminotransferases/blood
Biological Markers/blood
Chi-Square Distribution
Clinical Enzyme Tests
Female
Humans
Influenza A Virus, H1N1 Subtype/*pathogenicity
Influenza, Human/*diagnosis/mortality/radiography/therapy/virology
L-Lactate Dehydrogenase/blood
Lung/*radiography/virology
Male
Middle Aged
*Pandemics
Pneumonia, Viral/*diagnosis/mortality/radiography/therapy/virology
Predictive Value of Tests
Prognosis
Republic of Korea/epidemiology
Respiration, Artificial
Retrospective Studies
Risk Assessment
Risk Factors
Severity of Illness Index
*Tomography, X-Ray Computed
Young Adult