Infections after lung transplantation: time of occurrence, sites, and microbiologic etiologies

Infections in lung transplanted patients: A review

Lung transplantation can improve the survival of patients with severe chronic pulmonary disorders. However, the short- and long-term risk of infections can increase morbidity and mortality rates. A non-systematic review was performed to provide the most updated information on pathogen, host, and environment-related factors associated with the occurrence of bacterial, fungal, and viral infections as well as the most appropriate therapeutic options. Bacterial infections account for about 50% of all infectious diseases in lung transplanted patients, while viruses represent the second cause of infection accounting for one third of all infections. Almost 10% of patients develop invasive fungal infections during the first year after lung transplant. Pre-transplantation comorbidities, disruption of physical barriers during the surgery, and exposure to nosocomial pathogens during the hospital stay are directly associated with the occurrence of life-threatening infections. Empiric antimicrobial treatment after the assessment of individual risk factors, local epidemiology of drug-resistant pathogens and possible drug-drug interactions can improve the clinical outcomes.

Prevention and Management of Infections in Lung Transplant Recipients

Anti-rejection medications are essential in preventing organ rejection amongst solid organ transplant recipients; however, these agents also cause profound immunosuppression, predisposing lung transplant recipients (LTRs) to infectious complications. The timely management including prevention, diagnosis, and treatment of such infectious complications is vital to prevent significant morbidity and mortality in solid organ transplant recipients and allograft dysfunction. LTRs are inundated with microbes that may be recognized as commensals in hosts with intact immune systems. Bacterial infections are the most common ones, followed by viral pathogens. Indications of a brewing infectious process may be subtle. Hence, the importance of adapting vigilance around isolated hints through symptomatology and signs is pivotal. Signals to suggest an infectious process, such as fever and leukocytosis, may be dampened by immunosuppressive agents. One must also be vigilant about drug interactions of antibiotics and immunosuppressive agents. Treatment of infections can become challenging, as antimicrobials can interact with immunosuppressive agents, and antimicrobial resistance can surge under antimicrobial pressure. Transplant infectious disease physicians work in concert with transplant teams to obtain specimens for diagnostic testing and follow through with source control when possible. This heavily impacts medical decisions and fosters a multidisciplinary approach in management. Furthermore, the reduction of immunosuppression, although it augments the risk of allograft rejection, is as crucial as the initiation of appropriate antimicrobials when it comes to the management of infections.

Efficacy of different durations of antifungal prophylaxis with nebulized amphotericin B after lung transplantation: a retrospective cohort study

Background

Nebulized amphotericin B (NAB) is recommended for preventing invasive fungal diseases (IFDs) after lung transplantation. However, the optimal duration of NAB treatment is still unknown. This study aimed to compare the effectiveness of three different durations of antifungal prophylaxis with NAB after lung transplantation: a prolonged course beyond post-transplant 3 months, a medium course of 2 weeks to 3 months, and a short course of less than 2 weeks.

Methods

This a single-center retrospective cohort study analyzed 333 patients who underwent lung or heart-lung transplantation between January 2015 and November 2021.

Results

A prolonged course of NAB treatment was associated with a significantly lower incidence of IFDs (12.6%) at 1 year post-transplant compared with a short (50.9%) or a medium course (28.0%) (P<0.001). There was no significant difference in the rates of adverse effects among the three durations of NAB treatment (P>0.05). A prolonged course of NAB treatment was associated with a significantly higher 1-year survival rate (94.7%) compared with a short (36.8%) or a medium course (72.0%) (P<0.001).

Conclusions

A prolonged course of NAB treatment provided better protection against IFDs than a short or medium course after lung transplantation. Prolonged use of NAB did not significantly increase the incidence of adverse effects.

Epidemiology, management, and burden of cytomegalovirus in solid organ transplant recipients in selected countries outside of Europe and North America: A systematic review

BACKGROUND

Cytomegalovirus (CMV) is a frequent infectious complication following solid organ transplantation (SOT). Considering significant differences in healthcare systems, a systematic review was conducted to describe the epidemiology, management, and burden of CMV post-SOT in selected countries outside of Europe and North America.

METHODS

MEDLINE, Embase, and Cochrane databases were searched for observational studies in SOT recipients across 15 countries in the regions of Asia, Pacific, and Latin America (search period: January 1, 2011 to September 17, 2021). Outcomes included incidence of CMV infection/disease, recurrence, risk factors, CMV-related mortality, treatment patterns and guidelines, refractory and/or resistant CMV, patient-reported outcomes, and economic burden.

RESULTS

Of 2708 studies identified, 49 were eligible (n = 43/49; 87.8% in adults; n = 34/49, 69.4% in kidney recipients). Across studies, selection of CMV preventive strategy was based on CMV serostatus. Overall, rates of CMV infection (within 1 year) and CMV disease post-SOT were respectively, 10.3%-63.2% (9 studies) and 0%-19.0% (17 studies). Recurrence occurred in 35.4%-41.0% cases (3 studies) and up to 5.3% recipients died of CMV-associated causes (11 studies). Conventional treatments for CMV infection/disease included ganciclovir (GCV) or valganciclovir. Up to 4.4% patients were resistant to treatment (3 studies); no studies reported on refractory CMV. Treatment-related adverse events with GCV included neutropenia (2%-29%), anemia (13%-48%), leukopenia (11%-37%), and thrombocytopenia (13%-24%). Data on economic burden were scarce.

CONCLUSION

Outside of North America and Europe, rates of CMV infection/disease post-SOT are highly variable and CMV recurrence is frequent. CMV resistance and treatment-associated adverse events, including myelosuppression, highlight unmet needs with conventional therapy.

Trends and Outcomes in Lung Transplantation in Patients with and without Idiopathic Pulmonary Fibrosis in Spain during the Period 2016-2020

(1) Background: This paper aims to assess temporal trends (2016-2020) in incidence, patient's characteristics, complications, length of hospital stay (LOHS) and in-hospital mortality (IHM) among patients with and without idiopathic pulmonary fibrosis (IPF) undergoing lung transplantation (LTx). We also analyse the effect of the COVID-19 pandemic on LTx in these populations. (2) Methods: A retrospective, population-based observational study was conducted using the Spanish National Hospital Discharge Database. Multivariable adjustment was conducted with logistic regression to analyse the IHM. (3) Results: We identified 1777 admissions for LTx during the study period, of which 573 (32.2%) were performed in patients with IPF. The number of hospital admissions for LTx rose from 2016 to 2020, both in patients with and without IPF, but a marked reduction was observed from year 2019 to year 2020. Over time, the proportion of single LTx decreased and bilateral LTx increased significantly in both groups. The incidence of LTx complications increased significantly over time along with the increase in the incidence of IPF. No significant differences in the incidence of complications or in the IHM between patients with and without IPF were found. Suffering any complication of the LTx and pulmonary hypertension were conditions positively associated with IHM in patients with and without IPF. The IHM remained stable from 2016 to 2020 in both study populations and was not affected by the COVID pandemic. (4) Conclusions: Patients with IPF account for almost a third of all lung transplants. The number of LTx increased over time in patients with and without IPF, but a marked reduction was observed from 2019 to 2020. Although the proportion of LTx complications increased significantly over time in both groups, the IHM did not change. IPF was not associated with increased complications or IHM after LTx.

Complicações dos transplantes pulmonares na tomografia computadorizada: ensaio iconográfico

Resumo Transplantes pulmonares são procedimentos progressivamente mais realizados em todo o mundo como opção para tratamento de doenças pulmonares em estágio terminal. Apesar dos avanços laboratoriais, da técnica cirúrgica e da seleção de doadores e receptores, a mortalidade nesses procedimentos ainda é significativa, em razão de complicações típicas dos pacientes transplantados. Este trabalho consiste em uma revisão da literatura acerca do tema, ilustrando as complicações abordadas por meio de imagens de tomografia computadorizada.

Complications of lung transplantation on computed tomography: pictorial essay

Lung transplantation is becoming increasingly more common as an alternative treatment for end-stage lung disease. Despite advances in laboratory testing, surgical technique, and donor/recipient selection, lung transplantation is still associated with significant mortality, due to postoperative complications. This paper consists of a brief review of postoperative complications in lung transplant recipients, illustrating those complications with computed tomography images.

High-throughput next-generation sequencing for identifying pathogens during early-stage post-lung transplantation

BACKGROUND

High-throughput next-generation sequencing (HT-NGS) has the potential to detect a large variety of pathogens; however, the application of HT-NGS in lung transplant (LTx) recipients remains limited. We aimed to evaluate the value of HT-NGS for pathogen detection and diagnosis of pulmonary infection during early-stage post-lung transplantation.

METHODS

In this retrospective study, we enrolled 51 LTx recipients who underwent lung transplantation between January 2020 and December 2020. Bronchoalveolar lavage fluid (BALF) samples were collected for the detection of pathogens using both HT-NGS and conventional microbiological testing. The detection of pathogens and diagnostic performance of HT-NGS were compared with that of conventional methods.

RESULTS

HT-NGS provided a higher positive rate of pathogen detection than conventional microbiological testing (88.24% vs. 76.47%). The most common bacteria detected via HT-NGS during early-stage post-lung transplantation were Enterococcus, Staphylococcus, Pseudomonas and Klebsiella, while all fungi were Candida and all viruses were Herpesvirus. Uncommon pathogens, including Strongyloides, Legionella, and Mycobacterium abscesses were identified by HT-NGS. The sensitivity of HT-NGS for diagnosing pulmonary infection was significantly higher than that of conventional microbiological testing (97.14% vs. 68.57%; P < 0.001). For three LTx recipients, treatment regimens were adjusted according to the results of HT-NGS, leading to a complete recovery.

CONCLUSION

HT-NGS is a highly sensitive technique for pathogen detection, which may provide diagnostic advantages, especially in LTx recipients, contributing to the optimization of treatment regimens against pulmonary infection during early-stage post-lung transplantation.

Experience of International Air Transportation and Subsequent Lung Transplant in a Patient with COVID-19-associated Acute Respiratory Distress Syndrome: a Case Report

We report an inspiring case of a 55-year-old Korean female diagnosed with coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome (ARDS) in Mexico. The patient was assessed for lung transplant as a salvage therapy for treatment-refractory ARDS following no signs of clinical improvement for > 7 weeks, despite best treatment. The patient was transported from Mexico to Korea by air ambulance under venovenous extracorporeal membrane oxygenation (ECMO) support. She was successfully bridged to lung transplant on day 88, 49 days after the initiation of ECMO support. ECMO was successfully weaned at the end of operation, and no bleeding or primary graft dysfunction was observed within the first 72 hours. The patient was liberated from mechanical ventilation on postoperative day 9 and transferred to the general ward 5 days later. Despite the high doses of immunosuppressants, there was no evidence of viral reactivation after transplant. At 3 months post-transplantation, she was discharged to home without complication. Our experience suggests that successful lung transplant for COVID-19-associated ARDS is feasible even in a patient with prolonged pre-transplant ECMO support. Lung transplant may be considered a salvage therapy for COVID-19-associated ARDS that does not respond to conventional treatments.

Successful Lobar Lung Transplant From a Marginal Deceased Donor With a History of Treated Pulmonary Tuberculosis: A Case Report

The shortage of available donor lungs is a continuing clinical problem. Lobar lung transplant and the extension of donor lung criteria may expand the pool of donor lungs. We here report a case of lobar lung transplant from a marginal deceased donor with bronchiectasis and fibrosis at the left upper lobe and a history of treated pulmonary tuberculosis. Our experience with this case suggests that a lobar lung transplant can be considered not only for size mismatches but also for use of locally damaged lungs. In addition, lungs from a donor who received treatment for pulmonary tuberculosis may be feasible for transplant with chemoprophylaxis for latent tuberculosis infection. Our current case indicates one possible option to overcome the persistent shortage of available donor lungs.

Nebulized Amphotericin B Dosing Regimen for Aspergillus Prevention After Lung Transplant

OBJECTIVES

Lung transplant guidelines recommend nebulized amphotericin B with or without systemic antifungal agents for fungal prophylaxis. However, amphotericin formulation, dosing, and frequency vary between studies. We assessed the safety and effectiveness of nebulized amphotericin B to prevent Aspergillus infection in 2 regimens, ie, twice daily compared with 3 times daily.

MATERIALS AND METHODS

This was a single-center retrospective cohort study. We included patients at least 14 years old who underwent lung transplant and received nebulized amphotericin B alone or in combination with another antifungal agent either twice daily or 3 times daily. The primary endpoint was the incidence of lung Aspergillus infection, and the secondary endpoints were nebulized amphotericin B side effects and breakthrough Aspergillus infection.

RESULTS

A total of 84 patients were included. The group given nebulized amphotericin twice daily had a higher rate of Aspergillus infection at 17% compared with 4% in the group treated 3 times daily (P = .24). No serious side effects were reported, but coughing and diarrhea were more common in patients who received amphotericin B 3 times daily.

CONCLUSIONS

A systemic antifungal agent combined with nebulized amphotericin either twice or 3 times daily has been effective to prevent Aspergillus infection. Nebulized amphotericin twice daily may be a more viable option to increase a patient's adherence and decrease medication cost and side effects. However, a larger randomized controlled trial is needed to determine the best dosing regimen for nebulized amphotericin B as a fungal prophylaxis after lung transplant.

Infections in Lung Transplant Recipients during and after Prophylaxis

Background

The timeline of infections after lung transplantation has been changed with the introduction of new immunosuppressants and prophylaxis strategies. The study aimed to investigate the epidemiological characteristics of infectious diseases after lung transplantation in the current era.

Materials and Methods

All patients who underwent lung or heart–lung transplantation at our institution between October 29, 2008 and April 3, 2019 were enrolled. We retrospectively reviewed the patients' medical records till April 2, 2020.

Results

In total, 100 consecutive lung transplant recipients were enrolled. The median follow-up period was 28 months after lung transplantation. A total of 127 post–lung transplantation bacterial infections occurred. Catheter-related bloodstream infection (25/84, 29.8%) was the most common within 6 months and pneumonia (23/43, 53.5%) was the most common after 6 months. Most episodes (35/40, 87.5%) of respiratory viral infections occurred after 6 months, mainly as upper respiratory infections. The remaining episodes (5/40, 12.5%) mostly manifested as lower respiratory tract infections. Seventy cytomegalovirus infections observed in 43 patients were divided into 23 episodes occurring before and 47 episodes occurring after discontinuing prophylaxis. Of 10 episodes of cytomegalovirus disease, four occurred during prophylaxis and six occurred after prophylaxis. Of 23 episodes of post–lung transplantation fungal infection, 7 were aspergillosis and all occurred after the discontinuation of prophylaxis.

Conclusion

Lung transplant recipients experienced a high burden of infection even after 6 months, especially after the end of the prophylaxis period. Therefore, these patients should be continued to be monitored long-term for infectious disease.

A Retrospective Cohort Study of Risk Factors for Surgical Site Infection Following Lung Transplant

BACKGROUND

Surgical site infections (SSIs) are among the leading health care-associated infections as well as a major problem in the postoperative period of lung transplant recipients. Little is known about the risk factors in this specific population. The objective of this study was to identify the incidence, risk factors, and outcomes of SSI following lung transplant.

METHODS

Digital medical records of adult recipients subjected to lung transplant from July 2011 and June 2016 in a large Brazilian referral teaching public center were analyzed in this retrospective cohort follow-up.

RESULTS

Among the 121 recipients analyzed, 19 (15.7%) had SSI; of these, 11 (57.8%) had superficial incisional infections, 1 (5.2%) had a deep incisional infection, and 7 (36.8%) had organ/space infection. Recipient-related risk factors for SSI were high body mass index (P = .041), prolonged surgery time (P = .043), and prolonged duration of chest drain placement (P = .009). At the multiple logistic regression was found that each hour elapsed in the surgical time increased the odds of SSI by around 2 times (odds ratio 2.34; 95% CI, 1.46-4.53; P = .002). Donor-related risk factors included smoking status (P = .05) and positive bronchoalveolar lavage (P < .001). Having an SSI was associated with an increased length of stay in intensive care units (P = .003), reoperation (P = .014), and a higher 1-year mortality rate (P = .02).

CONCLUSIONS

The identified incidence rate was higher to that observed in the previous studies. The risk factors duration of chest tube placement and donor smoking status are different from those reported in the scientific literature.

Hyperammonemia by Ureaplasma urealyticum Pneumonia after Lung Transplantation

Ureaplasma urealyticum is a commensal of the female genital tract and can be detected as a pathogen in urethritis and vaginitis. Its importance as a respiratory pathogen beyond the field of neonatology remains controversial. We report a case of Ureaplasma-pneumonia in a recently lung-transplanted patient, with hyperammonemic syndrome.

The 51-year-old lung-transplanted female was admitted to the intensive care unit with new-onset reduction of her mental state due to hyperammonemia. A diagnostic bronchoscopy showed purulent bronchitis and multiple superficial ulcerations of the bronchial mucosa. The DNA-PCR from bronchoalveolar lavage confirmed the presence of Ureaplasma urealyticum in low concentration (about 5 * 10⁴ copies/ml), which was interpreted as evidence of infection and treated with Doxycycline intravenously. Ureaplasma was also identified by DNA-PCR in the biopsy specimens of the inflammatory enlarged mediastinal lymph nodes. Bilateral pleural effusions were found to be transudative and culturally sterile.

Ureaplasma-pneumonia can cause fatal hyperammonemia in lung-transplant patients and should be considered in the differential diagnosis of every unclear hyperammonemia with normal liver function. The early identification and treatment of the infection leads to clinical and biochemical resolution.

The Etiology and Prognosis of Delayed Postoperative Leukocytosis in Lung Transplant Recipients

BACKGROUND

Leukocytosis (white blood cell count >12 000/µL) in the delayed postoperative period (4-7 days) after lung transplantation is due to diverse etiologies. We aimed to describe the etiologies of delayed postoperative leukocytosis in lung transplant recipients and to evaluate the association of leukocytosis causes with short-term survival.

METHODS

A retrospective chart review of 274 lung transplantations performed in our institution during 2006 to 2013.

RESULTS

Delayed postoperative leukocytosis was seen in 159 (58.0%) of lung transplant recipients. In 57 (35.8%) of them, the etiology of the leukocytosis was not identified. The etiologies of leukocytosis that were identified were infection (n = 39), second surgery, acute rejection (n = 12), primary graft dysfunction (n = 3), multiple etiologies (n = 17), and other causes (n = 10). On multivariate analysis, delayed postoperative leukocytosis was one of the variables that most significantly associated with decreased survival in the entire sample (hazard ratio [HR] = 1.52, 95% confidence interval [CI]: 1.01-2.29, P = .040). On additional analysis for mortality assessing each leukocytosis subgroup, the data were acute graft rejection (HR = 8.21, 95% CI: 4.09-16.49, P < .001), second surgery (HR = 2.05, 95% CI: 1.08-3.90, P = .020), primary graft dysfunction (HR = 2.72, 95% CI: 0.65-11.33, P = .169), other causes (HR = 1.30, 95% CI: 0.47-3.62, P = .620), and unknown etiology (HR = 0.94, 95% CI: 0.54-1.62, P = .800).

CONCLUSIONS

Delayed post-lung transplant leukocytosis is a poor prognostic sign, especially when attributed to acute graft rejection, infection, and multiple etiologies. In the absence of an identifiable etiology, it can be attributed to postoperative reactive stress, is not associated with increased mortality, and likely does not warrant further diagnostic investigation.

Management and prophylaxis of bacterial and mycobacterial infections among lung transplant recipients

Bacterial and mycobacterial infections are associated with morbidity and mortality in lung transplant recipients. Infectious complications are categorized by timing post-transplant: <1, 1–6, and >6 months. The first month post-transplant is associated with the highest risk of infection. During this period, infections are most commonly healthcare-associated, and include infections related to surgical complications. The lungs and bloodstream are common sites of infections. Common healthcare-associated organisms include methicillin-resistant Staphylococcus aureus (MRSA), Gram-negative bacilli such as Pseudomonas aeruginosa, and Clostridioides difficile. More than 1-month post-transplant, opportunistic infections can occur. Tuberculosis occurs in 0.8–10% of lung transplant recipients which reflects variation in background prevalence. The majority of post-transplant tuberculosis stems from reactivation of untreated or undiagnosed latent tuberculosis. Most post-transplant tuberculosis occurs in the lungs and develops within a year of transplant. Non-tuberculous mycobacteria commonly colonize the lungs of lung transplant candidates and are often hard to eradicate even with prolonged courses of antimycobacterial agents. Drug interactions between antimycobacterial agents and calcineurin and mTOR inhibitors also complicates treatment post-transplant. Given that infection adversely impacts outcomes after lung transplant, and that anti-infective therapy is often less effective after transplant, infection prevention is key to long-term success. A comprehensive approach that includes pre-transplant evaluation, perioperative prophylaxis, long-term antimicrobial prophylaxis, immunization, and safer living at home and in the community, should be employed to minimize the risk of infection.

Infectious complications of bronchial stenosis in lung transplant recipients

BACKGROUND

Bronchial stenosis is a known complication of lung transplantation, but there are limited data regarding whether transplant recipients with bronchial stenosis develop more infectious complications than those without bronchial stenosis.

METHODS

We conducted a retrospective single-center observational cohort study between January 1, 2011 and September 29, 2016 of 35 lung transplant recipients diagnosed with bronchial stenosis and a random sample of 35 lung transplant recipients without bronchial stenosis. Data collected included donor/recipient demographic and anatomic information, respiratory cultures, episodes of respiratory infections diagnosed using CDC-NNIS criteria, hospitalizations, and 1-year all-cause mortality. Patients were followed up to 1 year after transplant.

RESULTS

Bronchial stenosis occurred at a median of 54 days post-transplant (range 5-365 days). Bronchial stenosis patients spent more time in the hospital (87.4 vs 46.8 days, P = 0.011) and had more total hospitalizations (4.54 vs 2.37, P < 0.01) than their counterparts. The relative risk of pneumonia among cases vs controls was 4.0 (95% CI 2.2-7.3, P < 0.01); for purulent tracheobronchitis the relative risk was 3.1 (95% CI 1.6-6.1, P < 0.01). Patients with bronchial stenosis were significantly more likely to have respiratory cultures growing Staphylococcus aureus (RR 5.0; P = 0.001) and Pseudomonas aeruginosa (RR 2.1, P = 0.026). Mortality within the first year following transplant was equal in both the groups (14.3% vs 14.3%).

CONCLUSIONS

There was no significant increase in 1-year mortality for lung transplant patients who developed bronchial stenosis. However, bronchial stenosis patients had significantly higher risks of pneumonia and tracheobronchitis, and spent more days in the hospital than those without bronchial stenosis.

Multidrug-resistant Acinetobacter baumannii infection in lung transplant recipients: risk factors and prognosis

Backgrounds: Infectious complication is an important cause of poor outcome of lung transplantation (LT). Infections with Acinetobacter baumannii (A. baumannii) are problematic, because of limited therapeutic option due to increasing resistance to antibiotics. However, there are few studies on A. baumannii infection in lung transplant recipients. Thus, we aimed to investigate epidemiology and risk factors for infection with A. baumannii in lung transplant recipients. Methods: Lung transplant recipients ≥18 years of age in a university hospital were enrolled in this retrospective cohort study. Risk factors for infection with multidrug resistant A. baumannii and 90-day mortality were analysed. Results: Fifty-one of 96 lung transplant recipients experienced A. baumannii infection. Infected patients had a significantly higher 90-day mortality rate than uninfected (19.6% vs. 2.2%, p = .009). High blood urea nitrogen (BUN) before transplantation (odds ratio [OR] 1.16; p = .008), long duration of surgery (OR 1.16; p = .029) and hypoalbuminemia before transplantation (OR 4.01; p = .037) were independent risk factors for infection with multidrug resistant A. baumannii. On multivariate analysis, severe thrombocytopenia (OR 28.69; p = .005), high serum creatinine (OR 1.48; p = .042) and infection with multidrug resistant A. baumannii (OR 22.58; p = .031) were independent risk factors for 90-day mortality. Conclusions: Prolonged surgery, high BUN and hypoalbuminemia before LT were significant risk factors for infection with multidrug resistant A. baumannii. Severe thrombocytopenia, high serum creatinine and infection with multidrug resistant A. baumannii infection were independent risk factors for 90-day mortality.

Long-Term Outcomes of Adult Lung Transplantation Recipients: A Single-Center Experience in South Korea

Background

Recently, the number of lung transplants in South Korea has increased. However, the long-term outcome data is limited. In this study, we aimed to investigate the long-term outcomes of adult lung transplantation recipients.

Methods

Among the patients that underwent lung transplantation at a tertiary referral center in South Korea between 2008 and 2017, adults patient who underwent deceased-donor lung transplantation with available follow-up data were enrolled. Their medical records were retrospectively reviewed.

Results

Through eligibility screening, we identified 60 adult patients that underwent lung (n=51) or heart-lung transplantation (n=9) during the observation period. Idiopathic pulmonary fibrosis (46.7%, 28/60) was the most frequent cause of lung transplantation. For all the 60 patients, the median follow-up duration for post-transplantation was 2.6 years (range, 0.01–7.6). During the post-transplantation follow-up period, 19 patients (31.7%) died at a median duration of 194 days. The survival rates were 75.5%, 67.6%, and 61.8% at 1 year, 3 years, and 5 years, respectively. Out of the 60 patients, 8 (13.3%) were diagnosed with chronic lung allograft dysfunction (CLAD), after a mean duration of 3.3±2.8 years post-transplantation. The CLAD development rate was 0%, 17.7%, and 25.8% at 1 year, 3 years, and 5 years, respectively. The most common newly developed post-transplantation comorbidity was the chronic kidney disease (CKD; 54.0%), followed by diabetes mellitus (25.9%).

Conclusion

Among the adult lung transplantation recipients at a South Korea tertiary referral center, the long-term survival rates were favorable. The proportion of patients who developed CLAD was not substantial. CKD was the most common post-transplantation comorbidity.

WITHDRAWN: Acute Cellular Rejection and Infection Rates in Alemtuzumab vs Traditional Induction Therapy Agents for Lung and Heart Transplantation: A Systematic Review and Meta-analysis

The Publisher regrets that this article is an accidental duplication of an article that has already been published in Transplant Proc. 2018; 50 (10):3739-3747, https://doi.org/10.1016/j.transproceed.2018.08.018. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Retransplantation Outcomes at a Large Lung Transplantation Program

Background

With the increase of primary lung transplantation across major centers worldwide, over the last several years the need of lung retransplant (ReTX) is likely to increase. Therefore, characterization of ReTX patients is prudent and necessary. Our study aimed to investigate and characterize the covariates and outcomes associated with lung ReTX survival in a single large U.S. transplant center.

Methods

Demographic, clinical diagnoses, and comorbidities were analyzed. Kaplan-Meier statistics were used to calculate and predict survival for 30 days and up to 3 years. Cox proportional modeling was used to determine the variables associated with mortality.

Results

Of included 684 lung transplants performed at the Houston Methodist Hospital between January 2009 and December 2015, 49 were lung ReTX. Median age of primary lung transplant (non-ReTX) and ReTx recipients was 62 and 49 years, respectively. Chronic graft rejection in the form of restrictive chronic lung allograft dysfunction and bronchiolitis obliterans syndrome was the main indications for ReTX. Compared with non-ReTX patients, ReTX patients had higher median lung allocation score (46.2 vs 37.0, respectively) and higher mortality after 6 months posttransplant. ReTX, older age, female sex, hospitalization 15 days or longer, estimated glomerular filtration rate less than 60, 6-minute walk distance less than 400 ft, and donor/recipient height ratio less than 1 were significantly associated with decreased 1-year patient and graft survival. Chronic graft rejection was still the major cause of death in the long-term follow-up recipients.

Conclusions

Our findings suggested that lung ReTX recipients have poor long-term survival outcomes. Lung ReTX should only be offered to carefully selected patients.

The First Living-Donor Lobar Lung Transplantation in Korea: a Case Report

Lung transplantation is the only treatment for end-stage lung disease, but the problem of donor shortage is unresolved issue. Herein, we report the first case of living-donor lobar lung transplantation (LDLLT) in Korea. A 19-year-old woman patient with idiopathic pulmonary artery hypertension received her father's right lower lobe and her mother's left lower lobe after pneumonectomy of both lungs in 2017. The patient has recovered well and is enjoying normal social activity. We think that LDLLT could be an alternative approach to deceased donor lung transplantation to overcome the shortage of lung donors.

Acute Cellular Rejection and Infection Rates in Alemtuzumab vs Traditional Induction Therapy Agents for Lung and Heart Transplantation: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Heart and lung transplantation is a high-risk procedure requiring intensive immunosuppressive therapy for preventing organ rejection. Alemtuzumab, a CD52-specific monoclonal antibody, is increasingly used for induction therapy compared with conventional agents. However, there has been no systematic review comparing its efficacy with traditional therapeutic drugs.

METHODS

PubMed and EMBASE were searched to October 1, 2017, for articles on alemtuzumab in cardiothoracic transplant surgery. Of the 433 studies retrieved, 8 were included in the final meta-analysis.

RESULTS

In lung transplantation, alemtuzumab use was associated with lower odds of acute cellular rejection compared with antithymocyte globulin (odds ratio [OR], 0.21; 95% CI, 0.11-0.40; P < .001), lower acute rejection rates (OR, 0.12; 95% CI, 0.03-0.55; P < .01), and infection rates (OR, 0.69; 95% CI, 0.35-1.36; P = .33) when compared with basiliximab. Multivariate meta-regression analysis found that mean age, male sex, single lung transplant, double lung transplant, cytomegalovirus or Epstein-Barr virus status, idiopathic pulmonary fibrosis, cystic fibrosis, and mean ischemic time did not significantly influence acute rejection outcomes. For heart transplantation, alemtuzumab use was associated with lower acute rejection rates when compared with tacrolimus (OR, 0.44; 95% CI, 0.30-0.66; P < .001).

CONCLUSIONS

Alemtuzumab use was associated with lower rejection rates when compared with conventional induction therapy agents (antithymocyte globulin, basiliximab, and tacrolimus) in heart and lung transplantation. However, this was based on observational studies. Randomized controlled trials are needed to verify its clinical use.

Microbiological findings in bronchoalveolar lavage fluid from lung transplant patients in Sweden

Background

Lung transplant patients experience a high risk of airway infections and microbial colonization of the lung due to constant exposure to the environment through inhaled microorganisms, denervation, reduced ciliary transport, and decreased cough.

Methods

In this nationwide prospective study on Swedish lung transplant patients, we evaluated the microbiological panorama of bacteria, fungi, and virus found in bronchoalveolar lavage fluid (BALF) obtained the first year after lung transplantation (LTx). Differences in microbiological findings depending of concomitant signs of infection and background factors were assessed.

Results

A total of 470 bronchoscopies from 126 patients were evaluated. Sixty‐two percent (n = 293) of BALF samples had positive microbiological finding(s). Forty‐six percent (n = 217) had bacterial growth, 29% (n = 137) fungal growth, and 9% (n = 43) were positive in viral PCR. In 38% of BALF samples (n = 181), a single microbe was found, whereas a combination of bacteria, fungi or virus was found in 24% (n = 112) of bronchoscopies. The most common microbiological findings were Candida albicans, Pseudomonas aeruginosa and coagulase negative Staphylococcus (in 42 (33%), 36 (29%), and 25 (20%) patients, respectively). Microbiological findings were similar in BALF from patients with and without signs of lung infection and the frequency of multidrug resistant (MDR) bacteria was low. No significant association was found between background factors and time to first lung infection.

Conclusion

This study gives important epidemiologic insights and reinforces that microbiological findings have to be evaluated in the light of clinical symptoms and endobronchial appearance in the assessment of lung infections in lung transplant patients.

Immunosuppressive Treatment and Its Effect on the Occurrence of Pneumocystis jiroveci, Mycoplasma pneumoniae, Chlamydophila pnemoniae, and Legionella pneumophila Infections/Colonizations Among Lung Transplant Recipients

BACKGROUND

The aim of the study was to assess the frequency of infections caused by Pneumocystis jiroveci, Chlamydophila pneumoniae, Legionella pneumophila, and Mycoplasma pneumoniae among lung transplant recipients in the context of immunosuppression.

METHODS

The study group consisted of 94 patients (37 women and 57 men; mean age 42.03 years) transplanted between 2009 and 2016 at the Silesia Center for Heart Diseases (SCCS). Immunosuppressive treatment (induction and maintenance therapy) was assessed. The immunofluorescence methods were used to detect the P. jiroveci, L. pneumophila, C. pneumoniae, and M. pneumoniae antigens in samples obtained from the respiratory tract.

RESULTS

Thirty-two of 94 graft recipients developed atypical or opportunistic infection. The median time of its occurrence was 178 days after transplantation. P. jiroveci was responsible for 84.38% of first infections. Five patients developed infection with P. jiroveci and C. pneumoniae. None of the infections occurred during induction of immunosuppression. An opportunistic or atypical infection developed in 19.35% of the patients treated with a tacrolimus-based regimen, and in 43.33% of patients on a cyclosporine-based regimen.

CONCLUSION

Infection with P. jiroveci is a recognized problem after lung transplantation and should be monitored. The percentage of infected patients is higher in patients treated with a cyclosporine-based regimen in comparison to those treated with tacrolimus.

Nontuberculous mycobacterial and Aspergillus infections among cadaveric lung transplant recipients in Japan

BACKGROUND

Lung transplantation is an effective treatment modality for respiratory failure. Chronic lung infections, including infections caused by nontuberculous mycobacteria (NTM) and Aspergillus, are difficult to control, and uncontrolled infections are relative contraindications for lung transplantation. However, few reports have documented the incidence and outcome of these infections in lung transplant recipients.

METHODS

To quantify the incidence and outcomes of colonization and disease caused by NTM and aspergillosis in recipients before and after lung transplantation, we reviewed the medical records and microbiology data from 240 consecutive cadaveric lung transplant recipients between 2000 and 2014.

RESULTS

Before lung transplantation, NTM and Aspergillus species were isolated from five (2.1%) and six (2.5%) patients, respectively, out of the total 240 recipients. All patients with NTM infection received treatment, resulting in culture conversion. They had no recurrence after lung transplantation. All patients with aspergillosis received treatment, one of whom had recurrence after lung transplantation. Over a median follow-up period of 3.3 years, NTM species were isolated after transplantation from eight of 240 patients (3.3%). Five of these patients met the criteria for NTM disease, and four of them received treatment. Four patients survived without a worsening of NTM disease. Over the same median follow-up period, Aspergillus species were isolated from seven of 240 patients (2.9%), six of whom received treatment.

CONCLUSIONS

Isolation of NTM or Aspergillus species from lung transplant recipients is uncommon. Adequate pre-transplant control and post-transplant management of NTM and Aspergillus infections allows for safe lung transplantation.

Voriconazole-refractory invasive aspergillosis

Invasive aspergillosis (IA) is one of the most common life-threatening complications in immunocompromised patients. Voriconazole is currently the drug of choice for IA treatment. However, some patients with IA suffer clinical deterioration despite voriconazole therapy. Management of voriconazole-refractory IA remains challenging; no useful recommendations have yet been made. Voriconazole-refractory IA can be further categorized as disease attributable to misdiagnosis or co-infection with another mold; inadequate blood voriconazole blood; inadequate tissue drug concentrations attributable to angioinvasion; immune reconstitution inflammatory syndrome; or infection with voriconazole-resistant Aspergillus. Hence, when encountering a case of voriconazole-refractory IA, it is necessary to schedule sequential tests to decide whether medical treatment or surgical intervention is appropriate; to adjust the voriconazole dose via drug monitoring; to seek CYP2C19 polymorphisms; to monitor serum galactomannan levels; and to examine the drug susceptibility of the causative Aspergillus species.

Pattern and Predictors of Hospital Readmission During the First Year After Lung Transplantation

Hospital readmission after lung transplantation negatively affects quality of life and resource utilization. A secondary analysis of data collected prospectively was conducted to identify the pattern of (incidence, count, cumulative duration), reasons for and predictors of readmission for 201 lung transplant recipients (LTRs) assessed at 2, 6, and 12 mo after discharge. The majority of LTRs (83.6%) were readmitted, and 64.2% had multiple readmissions. The median cumulative readmission duration was 19 days. The main reasons for readmission were other than infection or rejection (55.5%), infection only (25.4%), rejection only (9.9%), and infection and rejection (0.7%). LTRs who required reintubation (odds ratio [OR] 1.92; p = 0.008) or were discharged to care facilities (OR 2.78; p = 0.008) were at higher risk for readmission, with a 95.7% cumulative incidence of readmission at 12 mo. Thirty-day readmission (40.8%) was not significantly predicted by baseline characteristics. Predictors of higher readmission count were lower capacity to engage in self-care (incidence rate ratio [IRR] 0.99; p = 0.03) and discharge to care facilities (IRR 1.45; p = 0.01). Predictors of longer cumulative readmission duration were older age (arithmetic mean ratio [AMR] 1.02; p = 0.009), return to the intensive care unit (AMR 2.00; p = 0.01) and lower capacity to engage in self-care (AMR 0.99; p = 0.03). Identifying LTRs at risk may assist in optimizing predischarge care, discharge planning and long-term follow-up.

Serious fungal infections in Korea

Information on the incidence and prevalence of fungal infections is of critical value in public health policy. However, nationwide epidemiological data on fungal infections are scarce, due to a lack of surveillance and funding. The objective of this study was to estimate the disease burden of fungal infections in the Republic of Korea. An actuarial approach using a deterministic model was used for the estimation. Data on the number of populations at risk and the frequencies of fungal infections in those populations were obtained from national statistics reports and epidemiology papers. Approximately 1 million people were estimated to be affected by fungal infections every year. The burdens of candidemia (4.12 per 100,000), cryptococcal meningitis (0.09 per 100,000), and Pneumocystis pneumonia (0.51 per 100,000) in South Korea were estimated to be comparable to those in other countries. The prevalence of chronic pulmonary aspergillosis (22.4 per 100,000) was markedly high, probably due to the high burden of tuberculosis in Korea. The low burdens of allergic bronchopulmonary aspergillosis (56.9 per 100,000) and severe asthma with fungal sensitization (75.1 per 100,000) warrant further study. Oral candidiasis (539 per 100,000) was estimated to affect a much larger population than noted in previous studies. Our work provides valuable insight on the epidemiology of fungal infections; however, additional studies are needed.

Sterilization of Lung Matrices by Supercritical Carbon Dioxide

Lung engineering is a potential alternative to transplantation for patients with end-stage pulmonary failure. Two challenges critical to the successful development of an engineered lung developed from a decellularized scaffold include (i) the suppression of resident infectious bioburden in the lung matrix, and (ii) the ability to sterilize decellularized tissues while preserving the essential biological and mechanical features intact. To date, the majority of lungs are sterilized using high concentrations of peracetic acid (PAA) resulting in extracellular matrix (ECM) depletion. These mechanically altered tissues have little to no storage potential. In this study, we report a sterilizing technique using supercritical carbon dioxide (ScCO2) that can achieve a sterility assurance level 10(-6) in decellularized lung matrix. The effects of ScCO2 treatment on the histological, mechanical, and biochemical properties of the sterile decellularized lung were evaluated and compared with those of freshly decellularized lung matrix and with PAA-treated acellular lung. Exposure of the decellularized tissue to ScCO2 did not significantly alter tissue architecture, ECM content or organization (glycosaminoglycans, elastin, collagen, and laminin), observations of cell engraftment, or mechanical integrity of the tissue. Furthermore, these attributes of lung matrix did not change after 6 months in sterile buffer following sterilization with ScCO2, indicating that ScCO2 produces a matrix that is stable during storage. The current study's results indicate that ScCO2 can be used to sterilize acellular lung tissue while simultaneously preserving key biological components required for the function of the scaffold for regenerative medicine purposes.