Following a year of valganciclovir prophylaxis, a lung transplant recipient developed cytomegalovirus (CMV) infection that became resistant to ganciclovir, as confirmed by detection of UL97 kinase mutation M460V and a previously uncharacterized UL54 DNA polymerase mutation L516P. The latter mutation is now shown to confer ganciclovir and cidofovir resistance. As predicted from the viral genotype, foscarnet therapy was effective, but resumption of valganciclovir as secondary prophylaxis resulted in a plasma viral load rebound to 3.6 log10 copies/mL several weeks later. Valganciclovir was then replaced by letermovir, resulting in gradual viral load reduction in the first 5 weeks to below the quantitation limit (2.7 log10 copies/mL) for one week, followed by 10 weeks of rising viral loads reaching 4.3 log10 copies/mL while on letermovir. At this point, CMV genotypic testing revealed UL56 mutation C325Y, which confers absolute resistance to letermovir. Retreatment with foscarnet was successful. This case adds to the considerable list of proven ganciclovir resistance mutations, and provides an early experience with letermovir resistance after off-label therapeutic use. This experience is consistent with in vitro observations of rapid emergence of letermovir-resistant CMV after drug exposure.

Background Lung transplant recipients are at heightened risk for nocardiosis compared to other solid organ transplant recipients, with incidence rates as high as 9% and up to 30% associated mortality. No controlled studies assessing risk factors for nocardiosis in this high‐risk population have been reported. Methods Patients undergoing lung transplantation at a single center between 2012 and 2018 and diagnosed with nocardiosis post‐transplant were matched 1:2 to uninfected control subjects on the basis of age, transplant date, and sex. Results The incidence of nocardiosis in this lung transplant population was 3.4% (20/586), occurring a median of 9.4 months (range 4.4‐55.2) post‐transplant. In multivariable analysis, consistent use of trimethoprim/sulfamethoxazole (TMP/SMX) in the 12 weeks prior to diagnosis was independently associated with protection against nocardiosis (OR 0.038; 95% CI 0.01‐0.29; P = .002). Augmented immunosuppression in the 6 months prior to diagnosis was independently associated with the development of nocardiosis (OR 9.94; 95% CI 1.62‐ 61.00; P = .013). Six case patients (30%) had disseminated disease; all‐cause 6‐month mortality was 25%. The most common species was Nocardia farcinica (7/17 isolates), which was associated with dissemination and mortality. The most active antibiotics were TMP/SMX (100%), linezolid (100%), and amikacin (76%). Imipenem was only active against 4/17 isolates (24% susceptibility), with two isolates becoming non‐susceptible later in therapy. Conclusions Trimethoprim/sulfamethoxazole prophylaxis was shown to be protective against nocardiosis in lung transplant recipients, while augmented immunosuppression conferred increased risk. Institutional epidemiologic data are needed to best guide empiric therapy for Nocardia, as historical in vitro data may not predict local susceptibilities.

BackgroundThe drug pirfenidone has been shown to slow the progression and decrease mortality of idiopathic pulmonary fibrosis (IPF). Its exact mechanism is unknown, but it likely inhibits pro-fibrotic cytokine transforming growth factor beta, a known contributor to wound healing. We evaluated whether patients taking pirfenidone until lung transplantation had increased risk of impaired wound healing post-transplant. This information could determine whether pirfenidone should be discontinued prior to listing to allow for a wash-out period.MethodsWe retrospectively reviewed patients who underwent lung transplantation for pulmonary fibrosis at Norton Thoracic Institute in Phoenix, Arizona, from January 2014 to December 2015.ResultsWe describe 18 patients who took pirfenidone up to a month before transplant. Aside from one patient who experienced sternal dehiscence due to a surgical issue, all remaining patients did well with no evidence of airway dehiscence. Each of these 17 patients had been on pirfenidone for at least 30 days; nine patients had been on pirfenidone for over 90 days. Baseline characteristics including age, sex, body mass index, renal function, liver function, glucose level, pre-transplant corticosteroid use, and post-transplant immunosuppressant therapy were similar.ConclusionsIn our experience, pirfenidone may be safely continued until lung transplantation. Only one patient in our series experienced impaired wound healing related to a surgical issue, even when pirfenidone was continued until lung transplantation. We found no evidence of impaired wound healing or airway complications after lung transplantation in patients who were treated with pirfenidone before lung transplantation.