Objectives:

Chronic airway infections are a major cause of morbidity and mortality in patients with CF. The role of bacteria in acute bronchopulmonary exacerbation events is well known. Cases describing fungal involvement in pulmonary infections are known for ABPA and in patients who are immunocompromised, such as lung transplant recipients. Invasive pulmonary mycosis in immunocompetent CF patients has rarely been described. Diagnostic procedures and treatment guidelines are missing.

Methods:

In this study, from 12 CF centers in Germany 17 out of approximately 1200 patients with a high suspicion of an infection with a Scedosporium or Pseudallescheria spp. were evaluated. Criteria for invasive fungal infection were the following: increased sputum production, multiple pathogen detection in sputum or lavage samples, new pulmonary infiltrates, treatment failure with antibiotic therapy, unclear FEV1 decrease and specific antibody detection. Sputum and lavage samples were cultivated on SceSel + agar. Isolates were identified by sequencing of the ITS reagions of ribosomal DNA genes, antifungal susceptibility testing was performed using the microdilution reference method CSLI.

Conclusion:

Pulmonary infection by Scedosporium or Pseudallescheria spp. can also occur in immunocompetent patients with CF. For microbiological detection of fungi, ScelSel + agar or an adequate selective culture medium may be usefull. To confirm an invasive fungal infection, the detection of specific antibodies can be helpful. The therapy should be done with two systemic and one inhaled antifungal drug for at least 4 weeks. In some cases a much longer therapy is required.