Impact of loss to follow-up on survival estimation for cystic fibrosis.

PURPOSE: Deaths among those lost to follow-up (LTFU) in the Cystic Fibrosis Foundation Patient Registry (CFFPR) are critically important to the epidemiology of cystic fibrosis (CF). Unreported deaths could impact estimates of survival if LTFU is associated with disease trajectory. METHODS: We characterized the LTFU population (1986-2017) from the CFFPR and identified deaths via linkage with the National Death Index (NDI). Median predicted survival age and conditional survival were estimated with and without additional deaths and person-time from the NDI. RESULTS: Of the 10,582 individuals LTFU in the CFFPR, 2,460 (23.2%) matched to an NDI death record. Individuals who died after LTFU with a CF diagnosis were 43% female, 91% White/non-Hispanic, 59% had advanced CF lung disease based on last CFFPR recorded forced expiratory volume in one second (FEV1) %predicted <40 and 18% were post-lung transplant. Median predicted survival age during the most recent period available, 2013-2017, increased from 44.3 years (95% CI: 43.2, 45.7) to 45.8 years (95% CI 44.5, 47.1) with the inclusion of NDI data. CONCLUSIONS: Inclusion of deaths and additional person-time among those LTFU changed the point estimate of median predicted survival for most time periods and increased the point estimate from 2009 onwards.

Phage Therapy of Mycobacterium Infections: Compassionate Use of Phages in 20 Patients With Drug-Resistant Mycobacterial Disease.

BACKGROUND: Nontuberculous Mycobacterium infections, particularly Mycobacterium abscessus, are increasingly common among patients with cystic fibrosis and chronic bronchiectatic lung diseases. Treatment is challenging due to intrinsic antibiotic resistance. Bacteriophage therapy represents a potentially novel approach. Relatively few active lytic phages are available and there is great variation in phage susceptibilities among M. abscessus isolates, requiring personalized phage identification. METHODS: Mycobacterium isolates from 200 culture-positive patients with symptomatic disease were screened for phage susceptibilities. One or more lytic phages were identified for 55 isolates. Phages were administered intravenously, by aerosolization, or both to 20 patients on a compassionate use basis and patients were monitored for adverse reactions, clinical and microbiologic responses, the emergence of phage resistance, and phage neutralization in serum, sputum, or bronchoalveolar lavage fluid. RESULTS: No adverse reactions attributed to therapy were seen in any patient regardless of the pathogen, phages administered, or the route of delivery. Favorable clinical or microbiological responses were observed in 11 patients. Neutralizing antibodies were identified in serum after initiation of phage delivery intravenously in 8 patients, potentially contributing to lack of treatment response in 4 cases, but were not consistently associated with unfavorable responses in others. Eleven patients were treated with only a single phage, and no phage resistance was observed in any of these. CONCLUSIONS: Phage treatment of Mycobacterium infections is challenging due to the limited repertoire of therapeutically useful phages, but favorable clinical outcomes in patients lacking any other treatment options support continued development of adjunctive phage therapy for some mycobacterial infections.

Hypertonic saline has a prolonged effect on mucociliary clearance in adults with cystic fibrosis.

BACKGROUND: Inhaled hypertonic saline (HS) has been shown to increase mucociliary clearance (MCC) and improve clinical outcomes in adults and adolescents with cystic fibrosis (CF). However, in younger children with CF, a large study failed to demonstrate clinical benefits. This discrepancy could reflect pharmacodynamic differences in the MCC response to HS in different populations. We previously demonstrated the absence of a sustained effect of HS on MCC in healthy adults and in this study sought to characterize the durability of the MCC response to HS in adults with CF. METHODS: At two study sites, MCC was measured in CF adults using gamma scintigraphy during three separate visits: at baseline, 15 min, and 4 h after a single dose of HS (7% NaCl, 4 mL). Particle clearance rates at these visits were used to assess the durability of the MCC response to HS. RESULTS: The average 90-minute clearance rate measured 4 h after HS was significantly increased (21.81% ±â€¯12.8) when compared to baseline (13.77% ±â€¯8.7, p = .048) and showed no apparent slowing relative to the rate measured 15 min after HS. While not all subjects responded to HS, the acute response strongly predicted the sustained effect in these subjects (r = 0.896, p < .0001). CONCLUSIONS: These results suggest that, in contrast to healthy adults, a single dose of HS has a prolonged effect on MCC in adults with CF, which lasts at least 4 h. This may explain its clinical efficacy in this population.