Efficacy of sivelestat for acute lung injury due to severe bacterial pneumonia with systemic inflammatory response syndrome

Objective Neutrophil elastase is believed to play an important role in acute lung injury (ALI). Sivelestat is a small molecular weight neutrophil elastase inhibitor. Although some authors reported its efficacy in ALI, it is unclear whether sivelestat has good effects in ALI, especially in cases due to severe bacterial pneumonia. The purpose of this study is to investigate the effect of sivelestat to ALI due to severe bacterial pneumonia. Methods We performed a retrospective study of 28 patients who were admitted for severe bacterial pneumonia (pneumonia severity index; PSI class V). We investigated the patients' background, pneumonia severity score, the days from diagnosis of systemic inflammatory response syndrome (SIRS) to sivelestat administration, P/F ratio, SIRS score, and compared two groups: those who survived and those who died. Results There were no significant background differences between the two groups. In pneumonia severity score, chest X-ray film score was higher in the group of fatalities than in the survival group. In the survival cases, sivelestat had been administered earlier than in the cases that died. In the survival cases, improvement in P/F ratio, body temperature, heart rate, and respiratory rate were shown. The total number of SIRS scores also decreased in survival cases. Conclusion This study suggested the possibility that early administration of sivelestat may improve the ALI survival rate in severe pneumonia.