ABSTRACT
OBJECTIVES: This study was conducted in order to identify imaging features on three-dimensional computed tomography (CT) of unexplained chronic cough (UCC) patients with positive sputum cultures for filamentous Basidiomycetes (f-BM). METHODS: UCC outpatients who had been given various questionnaires for cough, pulmonary function tests, and fungal cultures of sputum were evaluated. Multidetector row CT (MDCT) was performed for three-dimensional CT analysis of the lungs. Retrospective analysis was carried out with three groups: f-BM culture-positive group, other fungal culture-positive group, and culture-negative group. The Kruskal-Wallis test, analysis of variance, Fischer exact test, χ2 test, Student's t test, Mann-Whitney U test, Spearman's correlation coefficient, and Dunn-Bonferroni post hoc method were used for statistical analysis. RESULTS: Of the 50 patients, 3 were excluded and the remaining 47 were included in the analysis. There were no significant differences in respiratory function or clinical characteristics among the three groups. The common features on high-resolution CT (HRCT) included tree-in-bud (TIB) pattern, multiple centrilobular nodules, and bronchial wall thickening. Bronchiolar mucus plugs were detected in 7 (15%) of 47 cases. Bronchiole wall thickness and %FEV1 appeared to be slightly correlated (p = 0.033, r = 0.357). The bronchiole walls were significantly thicker when mucus plugs were found (p = 0.010). Bronchiolar walls were the thickest and the score of mucus plugs was the highest in patients with f-BM culture-positive sputum (p = 0.008). CONCLUSIONS: Imaging findings for identifying f-BM culture-positive fungus-associated chronic cough (FACC) patients include high mucus plug scores and bronchiolar wall thickening on three-dimensional CT. KEY POINTS: ⢠Three-dimensional computed tomography helps clinicians assess patients with unexplained chronic cough and identify those with fungus-associated chronic cough. ⢠A retrospective single-center study showed that computed tomography images in patients with filamentous Basidiomycetes cultured from sputum had mucus plugs and bronchiolar wall thickening. ⢠UCC patients with sputum cultures positive for filamentous Basidiomycetes may have fine airway lesions that could not be detected without three-dimensional computed tomography.
