Clinical course of SARS-CoV-2 infection and recovery in lung transplant recipients.

BACKGROUND: Reports on outcomes following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in lung transplant recipients remain limited. METHODS: We performed a single-center, observational study of outcomes in lung transplant recipients diagnosed with SARS-CoV-2 between 5/1/2020 and 3/15/2022 that were followed for a median of 123 days. We analyzed changes in spirometry, acute lung allograft dysfunction (ALAD) incidence, hospitalization, mechanical ventilation needs, secondary infection, and survival. RESULTS: In our cohort of 336 patients, 103 developed coronavirus disease (COVID) (27 pre-Delta, 20 Delta, and 56 Omicron-era). Twenty-five patients (24%) required hospitalization and 10 patients ultimately died (10%). Among 85 survivors who completed ambulatory spirometry, COVID-19 did not alter change in forced expiratory volume in 1 s (FEV1 ) or forced vital capacity (FVC) over time compared to the preceding 6 months. The pre-COVID FEV1 change was -0.05 ml/day (IQR -0.50 to 0.60) compared to -0.20 ml/day (IQR -1.40 to 0.70) post-COVID (p = .16). The pre-COVID change in FVC was 0.20 ml/day (IQR -0.60 to 0.70) compared to 0.05 ml/day (IQR -1.00 to 1.10) post-COVID (p = .76). Although the cohort overall had stable lung function, 33 patients (39%) developed ALAD or accelerated chronic lung allograft dysfunction (FEV1 decline >10% from pre-COVID baseline). Nine patients (35%) with ALAD recovered lung function. Within 3 months of acute COVID infection, 18 patients (17%) developed secondary infections, the majority being bacterial pneumonia. Finally, vaccination with at least two doses of mRNA vaccine was not associated with improved outcomes. CONCLUSIONS: This study describes the natural history of SARS-CoV-2 infection in a large cohort of lung transplant recipients. Although one third of patients develop ALAD requiring augmented immunosuppression, infection with SARS-CoV-2 is not associated with worsening lung function.

Smoking-Related Home Oxygen Burn Injuries: Continued Cause for Alarm.

BACKGROUND: Home oxygen therapy is a mainstay of treatment for patients with various cardiopulmonary diseases. In spite of warnings against smoking while using home oxygen, many patients sustain burn injuries. OBJECTIVES: We aimed to quantify the morbidity and mortality of such patients admitted to our regional burn unit over a 6-year period. METHODS: A retrospective chart review of all patients admitted to a regional burn center from 2008 through 2013 was completed. Admitted patients sustaining burns secondary to smoking while using home oxygen therapy were selected as the study population to determine morbidity. RESULTS: Fifty-five subjects were admitted to the burn unit for smoking-related home oxygen injuries. The age range was 40-84 years. Almost all subjects were on home oxygen for chronic obstructive pulmonary disease (96%). Seventy-two percent of burns involved <5% of the total body surface area, 51% of patients were intubated, and of those 33% had evidence of inhalation injury. The hospital mortality rate was 14.5%. The mean length of hospital stay was 8.6 days, and 54.5% were discharged to a nursing home or another advanced facility. Finally, concomitant substance abuse was found in 27%, and a previous history of injury from smoking while on home oxygen was discovered in 14.5%. CONCLUSIONS: This single-center analysis is one of the largest describing burn injuries stemming from smoking while using home oxygen therapy. We identified the morbidity and mortality associated with these injuries. Ongoing education and careful consideration of prescribing home oxygen therapy for known smokers is highly encouraged.

Assessment of dd-cfDNA Levels in Clinically Stable Lung Allograft Recipients Beyond the Initial 2 y Posttransplant.

Donor-derived cell-free DNA (dd-cfDNA) is a useful biomarker for the diagnosis of acute allograft injury within the first 1 to 2 y after lung transplant, but its utility for diagnosing chronic lung allograft dysfunction (CLAD) has not yet been studied. Understanding baseline dd-cfDNA kinetics beyond the initial 2 y posttransplant is a necessary first step in determining the utility of dd-cfDNA as a CLAD biomarker. We seek to establish baseline dd-cfDNA% levels in clinically stable lung allograft recipients who are >2 y posttransplant. Methods: We performed a prospective, single-center, observational study to identify plasma dd-cfDNA levels in clinically stable lung allograft recipients >2 y posttransplant. Results: Fifty-one subjects were enrolled and ≥3 baseline dd-cfDNA measurements were acquired during a median of 252 d. The median baseline percent dd-cfDNA level in our cohort was 0.45% (interquartile range [IQR], 0.26-0.69). There were statistically significant differences in dd-cfDNA based on posttransplant duration (≤5 y posttransplant median 0.41% [IQR, 0.21-0.64] versus >5 y posttransplant median 0.50% [IQR, 0.33-0.76]; P < 0.02). However, the clinical significance of this small change in dd-cfDNA is uncertain because this magnitude of change is within the biologic test variation of 73%. Conclusions: This study is the first to define levels of dd-cfDNA in clinically stable patients who are >2 y post-lung transplant. These findings lay the groundwork for the study of dd-cfDNA as a possible biomarker for CLAD.