To the Editor: I read the recent publication by Gao et al on combined serological tests for pulmonary aspergillosis with a great interest.1 Gao et al concluded that “Combining two serological tests increased the specificity of diagnosis, but further trials are needed to prove the value of this approach.”1 First, clarification of the quality control process for the serological test in this study is necessary since this can affect interpretation of the results. In addition, I would like to add some ideas on this report. In addition to a trial on the diagnostic properties in other settings, a study on the cost effectiveness of this new approach should also be conducted. Also, there should be a diagnostic protocol for management of cases with controversial and discordant results from the combined serological tests. Indeed, the problem of cross reaction to other nonpathological Aspergillus spp should also be kept in mind when one uses the serological test for diagnosis.2 However, Lau et al suggested that “Notwithstanding the advantages of molecular tests, serological assays remain clinically useful for patient management.”3