Clinical implications of fungal isolation from sputum in adult patients with cystic fibrosis.

BACKGROUND/AIM Cystic fibrosis is an autosomal recessive disease with a defect in mucociliary activity that is characterized by recurrent pulmonary infections. Bacterial agents most frequently implicated in airway colonization and infection are Haemophilus influenzae, Staphylococcus spp. and Pseudomonas spp. Fungal isolation from sputum species is more common in adults. However, growth of fungal agent only in sputum culture in patients with cystic fibrosis is insufficient for the diagnosis of fungal diseases. There is limited and contraversial data about the clinical significance of fungal isolation in sputum cultures. The aim of the present study was to investigate the clinical outcomes including characteristics, lung function, therapy modalities and frequency of exacerbations and clinical significance of fungal isolation from sputum samples in adult patients with CF. MATERIALS AND METHODS This retrospective cohort study included patients who have been admitted between October 2017 and January 2019 in an Adult Cystic Fibrosis Unit. Patients were grouped according to fungal pathogenicity as; fungal disease group, colonization group, and non-isolated group. The data of the last one year, including patients demographics, clinical data, laboratory results, treatment modalities, results of cultured bacteria and fungus from sputum samples, respiratory function parameters, frequency of exacerbation and hospitalization were compared between groups. RESULTS A total of 330 sputum samples from 88 adult patients with CF were collected during the preceeding one year. Patients were divided into three groups, fungal disease group (n = 10, 11.4%), colonization group (n = 49, 55.7%), and non-isolated group (n = 29, 32.9%). Presence of pulmonary exacerbation and number of admission to emergency department and the number of positive cultures for bacteria from sputum were significantly higher in the fungal disease group (p = 0.03, p = 0.01 and p ?0.001). Patients in the fungal disease group had higher rate of administered antibiotics by parenteral route than other groups (p = 0.001) whereas lung function parameters were similar. Use of nutritional supplementation and parenteral antibiotherapy in the preceeding one year were the factors associated with elevated risk of fungal isolation. CONCLUSION Frequent use of parenteral antibiotics and use of nutritional supplementation were found to be independent risk factors for fungal isolation from sputum in adult CF patients.