A 10-year study reveals clinical and laboratory evidence for the ‘semi-invasive’ properties of chronic pulmonary aspergillosis

In recent years, infections caused by Aspergillus sp. have become an emerging focus of clinical microbiology and infectious disease, as the number of patients infected with Aspergillus sp. has increased markedly. Although chronic pulmonary aspergillosis (CPA) is considered a ‘semi-invasive’ or ‘intermediate’ disease, little data are available for the direct comparison of CPA with invasive pulmonary aspergillosis (IPA) and pulmonary aspergilloma (PA) to quantify invasiveness. In this study, we compared the characteristics of CPA with those of IPA and PA among hospitalized patients over a 10-year period. A total of 29, 51 and 31 cases of CPA, IPA and PA, respectively, were included. An increasing trend in galactomannan antigen seropositivity rate from PA (24.1%) to CPA (35.7%) to IPA (54.9%) and an opposite trend for anti-Aspergillus antibody (PA (71.0%) to CPA (45.8%) to IPA (7.1%)) were observed. Eight percent of CPA patients were infected with more than one Aspergillus sp. The survival rate of the CPA group also fell between the survival rate of PA and IPA, confirming the intermediate severity of CPA. The survival rate of the CPA group became significantly higher than that of the IPA group from day 180 onwards until 2 years after admission (P<0.05). The survival rate of the CPA group remained lower than that of the PA group from day 30 onwards until 2 years after admission. Poor prognostic factors for CPA included older age (P=0.019), higher total leukocyte count (P=0.011) and higher neutrophil count (P=0.012) on admission. This study provided clinical and laboratory evidence for the semi-invasive properties of CPA. Emerging Microbes and Infections (2016) 5, e37; doi:10.1038/emi.2016.31; published online 20 April 2016.