Association of plasma neutrophil elastase levels with other inflammatory mediators and clinical features in adult patients with moderate and severe pneumonia.
BACKGROUND
Plasma levels of neutrophil elastase (NE) are elevated in several inflammatory diseases and thus this enzyme might be a critical inflammatory marker. However, the role of NE in the pathogenesis of pneumonia has not been determined. The association between the severity of pneumonia and blood levels of inflammatory markers could be relevant to developing a useful indicator of severity and new therapeutic strategies for pneumonia.


METHODS
We searched for a useful predictive marker and a new therapeutic strategy against pneumonia, using a prospective, multicenter, population-based investigation. Several inflammatory markers in the circulation including NE, cytokines, defensins, C-reactive protein (CRP) and white blood cell (WBC) counts as well as clinical features were prospectively monitored in 28 adult patients with moderate (n=11) and severe pneumonia (n=17) over a period of 14 days.


RESULTS
The value of plasma NE was the highest at entry and significantly declined 2 days later. Trends of cytokines, defensins, CRP and WBC counts were similar but blunter. Microorganisms and the outcome of initial treatment did not significantly affect plasma NE levels. Baseline values of plasma NE were significantly higher in severe, than in moderate pneumonia and this difference between the two types of pneumonia persisted longer than those of any other markers.


CONCLUSIONS
Neutrophil elastase appears to play a critical role in severe pneumonia and determination of its concentration in blood could be a useful indicator of severity. Furthermore, clinical trials of anti-NE drugs in patients with severe pneumonia should be promising.
Matsuse
Hiroto
H
Second Department of Internal Medicine, Nagasaki University School of Medicine, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan. hmatsuse@nagasaki-u.ac.jp
Yanagihara
Katsunori
K
Mukae
Hiroshi
H
Tanaka
Kenji
K
Nakazato
Masamitsu
M
Kohno
Shigeru
S
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D016207:Cytokines / Q000097:blood; D023082:Defensins / Q000097:blood; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood*; D019272:Leukocyte Elastase / Q000097:blood*; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000097:blood* / Q000201:enzymology / Q000628:therapy; D011446:Prospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome
D015415:Biomarkers; D016207:Cytokines; D023082:Defensins; D018836:Inflammation Mediators; D019272:Leukocyte Elastase