Pediatric Pulmonology 50:1082–1089 (2015) Association of Chronic Candida albicans Respiratory Infection With a More Severe Lung Disease in Patients With Cystic Fibrosis Alex Gileles-Hillel, MD, 1 David Shoseyov, MD, 1,2,3 Itzhack Polacheck, PhD, 4 Maya Korem, MD, 4 Eitan Kerem, MD, 1,2,3 and Malena Cohen-Cymberknoh, MD 1,2,3 * Summary. Background: Despite the increase in fungal isolates, the significance of chronic Candida albicans airway colonization in CF is unclear. Aim: To investigate the impact of C. albicans airwaycolonization on CF disease severity. Methods: Longitudinal analysis of clinical data from CF patients followed during 2003–2009 at our CF center. Patients were stratified based on their C. albicans colonization status – chronic, intermittent, and none. Results: A total of 4,244 cultures were obtained from 91 patients (mean age 19.7 years, range 5–68). The three colonization groups were similar in age, gender,and body mass index (BMI). Compared to the non-colonized group (n ¼ 27, 30%), the chronic C. albicans colonization group (n ¼ 34, 37%), had a significantly lower FEV 1 percent predicted (74.3  23.1% vs. 93.9%  22.2) with a higher annual rate of FEV 1 decline ( 1.9  4.2% vs. 0.7  4.5%). The patients who were intermittently colonized with C. albicans had intermediate values. Conclusions: Chronic respiratory colonization of C. albicans is associated with worsening of FEV 1 in CF. Prospective studies are needed to confirm this finding and to corroborate whether indeed C. albicans drives a deleterious lung phenotype. Pediatr Pulmonol. 2015;50:1082–1089. ß 2015 Wiley Periodicals, Inc. Key words: Cystic fibrosis; disease progression; forced expiratory volume/physiology; sputum/microbiology. Funding source: Departmental grants. INTRODUCTION Cystic fibrosis (CF) is characterized by chronic inflammation and infection of the airways resulting in progressive damage leading to respiratory failure and early death. P. aeruginosa and S. aureus are the leading respiratory pathogens, however recent studies looking into the CF airway microbiome have uncovered other microorganisms. 1 Increased prevalence of fungi in CF respiratory cultures has been reported over the last decade, 2–4 Candida albicans the most common of them, with prevalence reaching 75% in some studies. 2,3 Other Candida species, including C. glabrata, C. parapsilosis, C. dubliniensis, and C. tropicalis, have also been reported, though with much lower prevalence. 4,5 Frequent use of antibiotics, as well as oral and inhaled steroids, potentially predisposes CF patients to colonization by Candida spp. 2 Clinical manifestations range in severity from asymptomatic colonization, to oral thrush, genital candidiasis, and bloodstream infections. 6,7 However, the consequences of chronic respiratory colonization by C. albicans in patients with CF remain unknown. The aims of this study were to investigate the prevalence and persistence of C. albicans in the 1 Department of Pediatrics, Hadassah Hebrew-University Medical Center, Jerusalem, Israel. 2 Pediatric Pulmonology Unit, Hadassah Hebrew-University Medical Center, Jerusalem, Israel. 3 Cystic Fibrosis Center, Hadassah Hebrew-University Medical Center, Jerusalem, Israel. 4 Department of Clinical Microbiology and Infectious Diseases, Hadassah Hebrew-University Medical Center, Jerusalem, Israel. Conflict of interest: None.  Correspondence to: Malena Cohen-Cymberknoh, MD, Department of Pediatrics, Pediatric Pulmonology and CF Center, Hadassah-Hebrew University Medical Center, POB 24035, Mt. Scopus (91240), Jerusalem, Israel. E-mail: malena@hadassah.org.il Received 23 February 2015; Revised 27 July 2015; Accepted 22 August 2015. DOI 10.1002/ppul.23302 Published online 18 September 2015 in Wiley Online Library (wileyonlinelibrary.com). ß 2015 Wiley Periodicals, Inc.