The Role Of Galactomanna Detection In The Diagnosis Of Pulmonary Aspergillosis In Non-neutropenic Patients

Objective: To compare the diagnostic accuracy of galactomannan(GM)detection by bronchoalveolar lavage fluid(BALF)and serum samples from non-neutropenic patients with invasive pulmonary aspergillosis(IPA)and non-IPA,and explore the optimal cut-off value for pulmonary aspergillosis and the factors leading to the false positivity of the BALF GM detection.Methods: Clinical data of non-neutropenic patients suspected of pulmonary aspergillosis who underwent the BALF and serum GM detection in the First Affiliated Hospital of Guangxi Medical University from January 2017 to June2018 were collected.They are divided into the experimental group and the control group according to the guidelines.The diagnostic indices of serum GM and BALF GM at different cut-off values were calculated.Additionally,the receiver operating characteristic(ROC)curves were constructed for the BALF GM and serum GM to acquire the optimal cutoff value.Furthermore,factors causing false positivity in the BALF GM detection were analyzed.Results: A total of 129 patients were enrolled based on clinical history,microbiological and histopathological examination.The experimental group include: 1 proven IPA patient,11 probable IPA patients,16 chronic pulmonaryaspergillosis patients and 1 allergic bronchopulmonary aspergillosis patient;the control group include 9 possible IPA patientis and 82 lung disease patients excluded pulmonary aspergillosis.The area under ROC curve of BALF is larger than that of serum.The optimal cut-off value of the BALF GM detection and the serum GM detection in IPA is 1.12 and 0.50,respectively;the optimal cut-off value of the BALF GM detection and the serum GM detection in non-IPA is1.03 and 0.56,respectively.Univariate analysis showed that infection of Talaromyces marneffei can lead to false positivity in BALF GM detection(P<0.05).Conclusions: The BALF GM detection is superior to the serum GM detection in the diagnosis of IPA and/or non-IPA in non-neutropenic patients.The infection of Talaromyces marneffei is an interfering factor leading to false positivity in the BALF GM detection.