Infectious complications of lung transplantation. Impact of cystic fibrosis

Aspergillus pulmonary infections in transplant recipients

Aspergillus infections are increasing in frequency in those undergoing solid organ and hematopoietic stem cell transplantation. The ongoing impact of Aspergillus infection on morbidity and mortality after transplantation makes this subject an area of intense clinical and research interest. This article discusses the evolving epidemiologic features of the infection and its management and diagnosis.

Mediastinal Mass Due to Aspergillus fumigatus After Lung Transplantation: A Case Report

We report a rare case of mediastinal mass caused by Aspergillus fumigatus in a lung transplant recipient. The patient presented 9 months after bilateral lung transplantation for cystic fibrosis with intermittent fevers and new onset atrial fibrillation/flutter caused by a 7-cm mediastinal mass invading the left atrium. The mass was resected, and a prolonged course of voriconazole and caspofungin was given, which resulted in a complete clinical response. Despite long-term suppressive therapy with voriconazole, a relapse occurred 16 months after the initial diagnosis. This case highlights the challenges in the prevention and treatment of invasive aspergillosis in lung transplant recipients.

[Lung transplant therapy for suppurative diseases]

OBJECTIVE

Lung transplantation is a valid therapeutic approach for patients with bronchiectasis. The objective of the present study was to evaluate our experience with bronchiectasis patients and compare the results in patients with cystic fibrosis to results in those with bronchiectasis caused by other processes.

PATIENTS AND METHOD

We carried out a retrospective study of bronchiectasis patients treated by lung transplantation in order to analyze demographic, functional and microbiological characteristics before and after transplantation, and survival.

RESULTS

From 1991 to 2002 lung transplants were performed on 171 patients, 44 of whom had suppurative lung disease (27 had cystic fibrosis and 17 had bronchiectasis caused by other processes). There were no significant differences in the demographic variables between the 2 groups. At transplantation, lung function variables showed severe bronchial obstruction (mean [SD] forced expiratory volume in 1 second of 808 [342] mL and forced vital capacity of 1,390 [611] mL) and respiratory insufficiency (PaO2 at 52 [10] mm Hg and PaCO2 at 48 [9] mm Hg). Only PaO2 was significantly lower in patients with bronchiectasis from causes other than cystic fibrosis. Airway colonization was present in 91% of the patients; Pseudomonas spp germs were detected in 64% of the cases and were multiresistant in 9%. In the early postoperative period germs were isolated in 59% of the cases, half of which involved the same germ as had been isolated before transplantation. One year after lung transplantation, 34% of the patients continued to have bronchial colonization. Survival at 1 year was 79% and at 5 years, 49%, with no significant difference between the patients with cystic fibrosis and those with other suppurative diseases, nor between the patients with and without Pseudomonas colonization. Only 2 patients had died of bacterial pneumonia at 1 month after transplantation.

CONCLUSIONS

Although airway colonization in patients with suppurative diseases complicates postoperative management, the results in terms of survival are good.

Renal and Vestibular Toxicity Due to Inhaled Tobramycin in a Lung Transplant Recipient

Chronic rejection is the major hurdle to long-term survival after lung transplantation. Endobronchial infection with Pseudomonas aeruginosa is common in patients with chronic rejection and this may further contribute to deterioration of the allograft. Inhaled tobramycin is commonly used to treat P aeruginosa airways infection in patients with cystic fibrosis. The safety of inhaled tobramycin in transplant recipients, however, has not been established. We describe the first report of a lung transplant recipient who developed renal failure and vestibular injury after receiving inhaled tobramycin. We review the literature regarding the safety of inhaled tobramycin and discuss potential mechanisms that may promote systemic toxicity in transplant recipients.

Functional status and quality of life in patients surviving 10 years after lung transplantation

Although many lung allograft recipients achieve long-term survival, there is a lack of published data regarding these patients' functional status and quality of life (QoL). We evaluated all 10-year survivors at our institution and, utilizing the SF-36 questionnaire, compared their QoL to population normative and chronic illness data. Twenty-eight (29%) of 96 patients survived > or =10 years following 11 single, 6 bilateral and 11 heart-lung procedures. At the most recent evaluation, median FEV(1) in single and double lung recipients was predicted to be 54% and 74%, respectively. Five (18%) patients had BOS score 0, 13 (46%) BOS 1, 5 (18%) BOS 2 and 5 (18%) BOS 3 and median time to BOS was 7 years. Four (14%) patients required renal replacement therapy. Three patients (11%) developed symptomatic osteoporosis, 2 (7%) post-transplant lymphoma and 1 (4%) an ischaemic stroke. Scores for physical function, role-physical/emotional and general health, but not mental health and bodily pain, were significantly lower compared to normative and chronic illness data. Energy and social-function scores were significantly lower than normative data alone. Long-term survival after lung transplantation is characterized by an absence or delayed development of BOS, low iatrogenic morbidity and preserved mental, but reduced physical health status.

A survey of anti-fungal management in lung transplantation

BACKGROUND

Fungal infections are an important complication of lung transplantation, but no controlled studies of their management have been performed. Knowledge of actual anti-fungal strategies may aid in the design of future prospective studies.

METHODS

Thirty-seven of 69 active lung transplant centers, accounting for 66% of all US lung transplantations, responded to our survey. The survey focused on fungal surveillance, pre- and post-transplant prophylaxis, and approach to fungal colonization.

RESULTS

The median number of lung transplantations performed by the centers in 1999 was 14 per year (range, 1-52), and median time that centers were in in operation was 9 years (range, 2-15 years). Seventy percent of centers had a transplant infectious diseases specialist. Pre-transplant fungal surveillance was performed by 81% of centers, with 67% of these surveying all patients and the remainder surveying only sub-sets of patients. Seventy-two percent of all centers started anti-fungal treatment if Aspergillus spp were isolated before transplantation. Itraconazole was the preferred agent (86%). After transplantation, 76% of centers gave anti-fungal prophylaxis, although 24% of these did so only in selected patients. Prophylactic agents in order of preference were inhaled amphotericin B (61%), itraconazole (46%), parenteral amphotericin formulations (25%), and fluconazole (21%); many centers used more than 1 agent. Prophylaxis was initiated within 24 hours by 71% and within 1 week by all centers. Median duration of prophylaxis was 3 months (range, <1 month-lifetime). All 37 centers used anti-fungal therapy if colonization with Aspergillus spp was detected for a median duration of 4.5 months. Itraconazole was the preferred agent. Only 59% of centers treated patients colonized with Candida spp. In a statistical analysis, centers with larger volumes were less likely to treat pre-transplant colonization with Candida spp but more likely to use agents other than itraconazole for post-transplant colonization with Aspergillus spp. Only 14% of centers engaged in any anti-fungal research at the time of the survey.

CONCLUSIONS

The majority of surveyed lung transplant programs actively manage fungal infection with prophylaxis or pre-emptive therapy, despite the absence of controlled trials. This survey may provide an impetus and a basis for designing prospective studies.

Nontuberculous mycobacterial infection in hematopoietic stem cell and solid organ transplant recipients

Nontuberculous mycobacteria (NTM) are ubiquitous environmental organisms. In immunocompetent hosts, they are a rare cause of disease. In immunocompromised hosts, disease due to NTM is well documented. Reports of NTM disease have increased in hematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT) recipients. This increase may reflect increased numbers of transplants, intensification of immune suppressive regimens, prolonged survival of transplant recipients, and/or improved diagnostic techniques. The difficulty of diagnosis and the impact associated with infections due to NTM in HSCT and SOT recipients necessitates that, to ensure prompt diagnosis and early initiation of therapy, a high level of suspicion for NTM disease be maintained. The most common manifestations of NTM infection in SOT recipients include cutaneous and pleuropulmonary disease, and, in HSCT recipients, catheter-related infection. Skin and pulmonary lesions should be biopsied for histologic examination, special staining, and microbiologic cultures, including cultures for bacteria, Nocardia species, fungi, and mycobacteria. Mycobacterial infections associated with catheters may be documented by tunnel or blood (isolator) cultures. Susceptibility testing of mycobacterial isolates is an essential component of optimal care. The frequent isolation of NTM other than Mycobacterium avium complex (MAC) from transplant recipients limits the extrapolation of therapeutic data from human immunodeficiency virus-infected individuals to the population of transplant recipients. Issues involved in the management of NTM disease in transplant recipients are characterized by a case of disseminated infection due to Mycobacterium avium complex in a lung transplant recipient, with a review of the relevant literature.

Effects of sinus surgery in patients with cystic fibrosis after lung transplantation: a 10-year experience

Chronic infectious rhinosinusitis with Pseudomonas aeruginosa is common in cystic fibrosis and may result in allograft infection after lung transplantation. Sinus surgery followed by nasal care may reduce these adverse effects. Sinus surgery was performed in 37 patients with cystic fibrosis after transplantation. Bacteriology of sinus aspirates (n=771) and bronchoalveolar lavage (BAL) (n=256) was correlated with clinical data. Sinus surgery was successful in 54% and partially successful in 27% of patients. A significant correlation between negative sinus aspirates and negative BAL and between positive sinus aspirates and positive BAL (P<0.0001) was found. Successful sinus management led to a lower incidence of tracheobronchitis and pneumonia (P=0.009) and a trend toward a lower incidence of bronchiolitis obliterans syndrome (P=0.23). Sinus surgery followed by daily nasal douching may control posttransplant lower airway colonization and infection. In the long term, this concept may lead to less bronchiolitis obliterans syndrome by decreasing bronchiolar inflammation.

Human leukocyte antigen mismatches predispose to the severity of bronchiolitis obliterans syndrome after lung transplantation

BACKGROUND

Obliterative bronchiolitis (OB) is the most important cause of long-term morbidity and mortality in lung transplant recipients, and probably results from alloimmune airway injury. Bronchiolitis obliterans syndrome (BOS), defined as a staged decline in pulmonary function, is the clinical correlate of OB.

OBJECTIVE

Evaluation of the risk and severity of BOS on the basis of the incompatibility of donor and recipient human leukocyte antigen (HLA) molecules.

DESIGN

Retrospective cohort study.

SETTING

Large university hospital.

PARTICIPANTS

Lung transplant recipients between January 1990 and January 2000.

MEASUREMENTS

We determined the BOS stage using internationally promulgated guidelines with a minor modification on all recipients at their 4-year transplant anniversary. Recipients whose graft function had deteriorated or who died due to causes other than BOS were excluded from the study. HLA loci mismatches and other covariables, including recipient age, donor age, cytomegalovirus (CMV) mismatch, cold ischemic time, use of cardiopulmonary bypass, ventilatory days, episodes of acute rejection and CMV pneumonitis, mean trough cyclosporin A (CsA) level, episodes of subtherapeutic CsA levels, and histopathology of OB and diffuse alveolar damage were entered into the analysis of BOS predictors.

RESULTS

Sixty-four patients met the inclusion and exclusion criteria of the study at the 4-year posttransplant time point. In univariate analyses, the number of combined HLA-A and HLA-B mismatches was strongly associated with the stage of BOS at 4 years (p = 0.002). This association remained significant after the inclusion of other potential risk factors for BOS in multiple linear regression models. Pretransplant and posttransplant proportional odds models confirmed that the increasing number of combined HLA-A and HLA-B mismatches increased the overall severity of BOS (adjusted odds ratio, 1.84 [p = 0.035] vs 1.69 [p = 0.067], respectively). A trend toward significance was seen with HLA-DR mismatching (p = 0.17).

CONCLUSIONS

The degree of HLA class I mismatching between donors and recipients predisposes lung transplant recipients to the development and severity of BOS.

Aspergillus infection in lung transplant recipients with cystic fibrosis: risk factors and outcomes comparison to other types of transplant recipients

STUDY OBJECTIVES

To characterize Aspergillus infections in lung transplant recipients with cystic fibrosis (CF).

DESIGN

A retrospective analysis of 32 consecutive lung transplant recipients with CF who underwent bilateral lung transplant at the University of Wisconsin from 1994 to 2000 to determine the incidence, risk factors, and consequences of Aspergillus infection. The findings were compared to 101 non-CF recipients of lung transplants (93) and heart-lung transplants (8) for other transplant indications.

SETTING

A university hospital.

PATIENTS OR PARTICIPANTS

Lung transplant recipients with CF or other indications for transplantation.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Seventeen of 32 CF recipients (53%) had Aspergillus fumigatus isolated from their respiratory secretions prior to undergoing transplantation. Ten of these 17 (59%) recipients had A fumigatus persistently found in their respiratory secretions posttransplant vs 6 of 15 CF patients (40%) who had not been colonized pretransplant and 28 of 101 of the non-CF recipients (28%). Four of the preoperatively colonized CF recipients developed tracheobronchial aspergillosis (TBA) just distal to the bronchial anastomoses, and one recipient had dehiscence of the involved anastomosis. None of the CF recipients developed disseminated aspergillosis or pneumonia. Prophylactic antifungal therapy did not prevent TBA, and IV amphotericin B therapy was required to clear the infection in all four patients, with endobronchial debridement of necrotic tissue required in two of them. In contrast, 10 of the non-CF (10%) recipients developed Aspergillus infections posttransplant (TBA, 4 recipients; pneumonitis, 6 recipients), and only 3 patients had successful treatment and long-term survival (TBA, 2 patients; pneumonia, 1 patient). Donor lung ischemia time, cytomegalovirus infection or pneumonia, or pretransplant mechanical ventilation did not increase the risk of developing TBA in CF recipients.

CONCLUSIONS

The risk of TBA for patients receiving lung transplants for CF warrants early surveillance bronchoscopy to detect TBA, particularly in recipients with pretransplant colonization.

Saprophytic fungal infections and complications involving the bronchial anastomosis following human lung transplantation

STUDY OBJECTIVE

To demonstrate an association between saprophytic fungal infections occurring at the bronchial anastomosis (BA) and the development of additional complications arising at this site.

DESIGN

Retrospective review.

SETTING

University lung transplant center.

MATERIALS AND METHODS

Review of all single-lung and double-lung transplant (LTX) recipients who underwent transplantation between June 1993 and December 2000. All recipients were subjected to surveillance bronchoscopy with biopsy at predetermined intervals and when clinically indicated. Bronchial wash fluid and biopsy material were examined using appropriate fungal stains and culture techniques. An infection was defined when fungal organisms were identified in tissue specimens.

RESULTS

Fifteen saprophytic fungal infections involving the BA were identified in 61 LTX recipients (24.6%) who survived a minimum of 75 days post-transplantation. Infections were attributed to Aspergillus sp (n = 9), Candida sp (n = 2), Torulopsis sp (n = 1), and mixed flora (ie, Penicillium + Candida, two patients; and Aspergillus + Candida, one patient). Saprophytic fungal infections occurred by a median of postoperative day 35 (range, 13 to 159 days). Airway complications involving the BA ultimately developed in 11 of 61 recipients (18%). These complications included symptomatic bronchial stenosis (nine patients), bronchomalacia (one patient), and fatal hemorrhage (one patient). Bronchial complications arose in 7 of 15 recipients (46.7%) with saprophytic fungal infections of the BA in contrast to 4 of 46 (8.7%) without infections (p = 0.003, Fisher exact test). Also demonstrated was a positive correlation between anastomotic infections and bronchial complications (Phi coefficient = 0.43; p = 0.001), while logistic regression analysis revealed that the absence of anastomotic infections predicted the absence of such complications (p = 0.002). The risk of developing an additional complication following an anastomotic infection in patients with infections was five times that of those recipients without an infection (relative risk, 5.36; 95% confidence interval [CI], 1.82 to 15.79). The odds in favor of a bronchial complication following an infection were eight times greater than in those recipients without infection (odds ratio, 8.31; 95% CI, 1.96 to 35.16).

CONCLUSIONS

Following LTX, saprophytic fungal infections of the BA are associated with serious airway complications.

Nontuberculous mycobacteria in the setting of cystic fibrosis

Nontuberculous mycobacterial pulmonary infections are increasingly recognized in patients with CF. This may reflect the increasing longevity of this population with increased environmental exposure time, a higher clinical index of suspicion, and/or some as yet unidentified predisposing factor(s). The most common species of NTM in CF is MAC, followed by M abscessus. We recommend that adult patients with CF be screened for the presence of nontuberculous mycobacteria in pulmonary secretions on a regular basis, and that consideration be given to this diagnosis if a patient has an escalating pattern of exacerbations or admissions. Positive cultures are likely to indicate disease if they are multiple or if a patient has clinical evidence of pulmonary disease exacerbation (increased cough, increased purulence of secretions, systemic manifestations such as fever, weight loss) that is not responding to conventional antibiotic therapy. Cystic fibrosis patients who do not respond to treatment for the usual organisms should be carefully re-evaluated for the presence of NTM and treated with a macrolide-containing multidrug regimen directed against the identified NTM if diagnostic criteria are met. Novel treatments with cytokines and intermittent dosing of antibiotics are currently under investigation in non-CF populations and may have applicability to CF in the future.

Invasive and Allergic Fungal Sinusitis

Fungal sinusitis encompasses a wide range of clinical syndromes. Disease is classified into four major categories: 1) acute invasive fungal sinusitis, 2) chronic invasive fungal sinusitis, 3) mycetoma, and 4) allergic fungal sinusitis. Acute disease is most often a fulminant, life-threatening process seen in immunocompromised patients. Treatment requires prompt antifungal therapy and extensive surgical debridement. Other types of fungal sinusitis are more indolent. For chronic invasive sinusitis, a combination of surgical debridement and antifungal agents is the cornerstone of treatment. Mycetomas can usually be extirpated surgically and do not require therapy with antifungal agents. Treatment of allergic fungal sinusitis remains controversial, but most current management regimens utilize surgical debridement combined with corticosteroid therapy, rather than antifungal agents.

Perioperative care of the lung transplant patient

Improvements in the perioperative management of lung transplant recipients have produced a 90% survival in the first 30 days following surgery. Detailed attention to donor organ procurement and preservation of the allograft are important in ensuring an early successful outcome. Early antibacterial administration based on donor or pretransplant cultures and antiviral therapy in CMV-negative recipients assist in avoiding early infectious complications. Development of hypoxemia or hemodynamic instability in the perioperative period requires a rapid, systematic evaluation with attention to mechanical, immunologic, or infectious causes. Nonpulmonary complications are not infrequent in lung transplant recipients.

Imaging of the chest after lung transplantation

Lung transplantation is a well-accepted treatment for numerous lung diseases when medical or surgical therapy is ineffective or unavailable and the patient has a limited life expectancy (usually less than 2 to 3 years). When appropriate, single-lung transplantation is the preferred procedure because of a critical shortage of available donor lungs. Preoperative imaging is useful for selecting which lung should be transplanted, size matching between donor lung and recipient thorax, and screening for malignancy. Cardiac-related deaths, infection, and primary graft failure are the leading causes of perioperative death. Obliterative bronchiolitis is the "Achilles heel" of lung transplantation and accounts for the largest number of late deaths. This article reviews the preoperative, perioperative, and postoperative considerations and the utility of radiologic imaging after lung transplantation.

Nontuberculous mycobacteria in cystic fibrosis

The incidence of NTM pulmonary infections increasingly is recognized in patients with CF. This may reflect the increasing longevity of this population with increased environmental exposure time, a high index of suspicion, and/or some as of yet unidentified predisposing factor(s). The most common species of NTM in CF is MAC, followed by M. abscessus. The authors recommend that adult patients with CF be screened for the presence of NTM pulmonary secretions on a regular basis. Positive cultures are likely to indicate disease if they are multiple or if a patient has clinical evidence of pulmonary disease exacerbation (increased cough, increased purulence of secretions, or systemic manifestations such as fever and weight loss) that is not responding to conventional antibiotic therapy. CF patients who do not respond to treatment for the usual organisms should be re-evaluated for the presence of NTM and treated with a macrolide-containing regimen directed against the identified NTM if diagnostic criteria are met. Novel treatments with cytokines and intermittent dosing of antibiotics are currently under investigation.

Aspergillosis in lung transplantation: incidence, risk factors, and prophylactic strategies

Invasive aspergillosis remains a significant cause of morbidity and mortality in transplantation, especially lung and allogeneic bone marrow transplant recipients. The epidemiology, classic and newly recognized risk factors, and incidence of aspergillosis are reviewed. Risk factors include environmental exposures, airway colonization, profound immunosuppression, neutropenia, prior cytomegalovirus infection, and renal dysfunction. Clinical and radiographic presentations of invasive aspergillosis are discussed, including some unusual manifestations in lung transplant recipients. Early and accurate diagnosis of aspergillosis remains a challenge, and diagnostic strategies are reviewed, with an emphasis on the chest computerized tomography scan and on transbronchial or open lung biopsy. Recent advances include prophylactic and pre-emptive antifungal strategies, newer therapeutic agents, and improved risk stratification.

Infectious complications of lung transplantation

Lung transplantation is associated with a high incidence of infection which directly impacts the morbidity and mortality associated with the procedure. In addition, these infections may also have immunologic consequences that play a role in the evolution of lung injury syndromes, resulting in earlier loss of graft than otherwise would be expected to occur. Although bacteria are responsible for the majority of infections following lung transplantation, fungal infections are associated with the highest mortality. This paper is an overview of the major infectious complications encountered in the lung transplant population. The epidemiology, prophylaxis, and treatment of infections following lung transplantation are critical areas for continued research.

Burkholderia cepacia complex: a contraindication to lung transplantation in cystic fibrosis?

Previous studies have indicated that pulmonary infection with Burkholderia cepacia is associated with poor clinical outcome after lung transplantation in cystic fibrosis (CF). Many treatment centers consider B. cepacia infection an absolute contraindication to lung transplantation. However, the B. cepacia complex actually consists of several closely related bacterial species. Although each of these has been isolated from CF sputum culture, certain species are much more frequently recovered than others, and it is not yet clear whether all species have the same potential for virulence in CF. Additional study is needed to better define the relative risks associated with each species of the B. cepacia complex.

Medical Management Considerations for Patients With Lung Transplantation

Lung transplantation has become an accepted modality for the treatment of end-stage lung disease. Adult and pediatric patients with a variety of lung diseases, including cystic fibrosis, chronic obstructive pulmonary disease, and idiopathic pulmonary fibrosis are candidates for lung transplantation. Lung transplantation can extend survival and improve quality of life for these patients. With the introduction of new immunosuppressive agents and enhanced surgical and medical care, both short- and long-term morbidity and mortality in these populations, although not as good as other transplant types, are improving. After lung transplantation, recipients continue to face a number of obstacles including post-operative complications, complex drug regimens, drug-induced toxicities, infection, and rejection. An understanding of the management and monitoring issues after lung transplantation is the focus of this review.

[Infection and colonization by Scedosporium prolificans]

BACKGROUND

Scedosporium prolificans is a dematiaceous fungus that is known to cause a wide spectrum of infections in humans, bearing a severity and a prognosis that is relationed with the patients immune status.

METHODS

A retrospective review was made of the clinical charts of all patients who developed positive S. prolificans cultures in our centre from 1990 to 2000. Isolates were identified by colonial morphology and microscopic features. The in vitro susceptibility was evaluated using the microdilution method according to NCCLS.

RESULTS

S. prolificans was isolated in 15 patients. Eight were affected with cystic fibrosis and the isolation of S. prolificans in their airways did not worsen their clinical status. Among the remaining 7 cases there were five leukemic patients with neutropenia and two immunocompetent hosts with cutaneous infection and endocarditis. Four of five neutropenic patients died of sudden sepsis and S. prolificans was isolated from blood cultures made a few days before their death, and the fifth neutropenic case suffered a bilateral pneumonia with improving course probably due to recovery from neutropenia. As to the immunocompetent group the clinical course was good in the cutaneous infection case, but the endocarditis case died four days after the antifungical therapy was started. All the isolates tested were found to be resistant to amphotericin, 5 flucytosine, fluconazole, itraconazole, voriconazole, miconazole and terbinafine.

CONCLUSIONS

Scedosporium prolificans is a fungal pathogen that colonizes the airways of patients affected with cystic fibrosis. It can also cause a wide variety of infections, whose severity and prognosis depends on the patients immune status. Due to the resistance of this fungus to antifungal drugs, the therapeutic options are limited. Only with the correction of neutropenia and surgery in local infections in immunocompetent hosts it has been possible to cure these infections.

Epidemiology and management of infections after lung transplantation

Lung transplantation has become an accepted treatment for end-stage pulmonary parenchymal and vascular diseases. Infections still are the most common cause of early and late morbidity and mortality in lung transplant recipients. Bacterial infections comprise approximately half of all infectious complications. Cytomegalovirus (CMV) infections and disease have become less frequent, because of prophylaxis with ganciclovir. Because CMV is also involved in the pathogenesis of obliterative bronchiolitis, the frequency of this infection may also reduce the occurrence of this main obstacle to successful lung transplantation. Invasive fungal infections remain a problem, but they have also decreased in frequency because of better control of risk factors such as CMV disease and preemptive antifungal therapy. Nonherpes respiratory viral infections have emerged as a serious problem. Their severity may be reduced by treatment with ribavirin. Meticulous postoperative surveillance, however, is still crucial for the management of lung transplant patients with respect to early detection and treatment of rejection and infection.

Prophylaxis strategies for solid-organ transplantation

In addition to the net state of immunosuppression, the risk of infection after transplantation is largely determined by the transplant recipient's epidemiologic exposures. Potential sources of infection in the transplant recipient include the environment and the recipient's endogenous flora. This article presents aspects of prevention of infection after solid-organ transplantation such as avoidance of epidemiologic exposures, antibacterial prophylaxis, prophylaxis for tuberculin-positive transplant recipients, and prophylaxis against infections with Pneumocystis carinii and Toxoplasma gondii.

Infectious complications of solid organ transplantations

The rate of infectious complications in SOT recipients has declined dramatically. As improvements in immunosuppressive therapy, surgical techniques, and diagnostics and antimicrobial treatment continue, further declines in infectious complications are expected. Refinements to preemptive therapy for high-risk patients are likely to contribute further to this decrease. Further investigation is required to define what role various infectious agents play in chronic allograft injury and rejection.

Infection with Burkholderia cepacia in cystic fibrosis: outcome following lung transplantation

As a result of concern over excessive mortality after lung transplantation, many transplant programs refuse to accept cystic fibrosis (CF) patients infected with Burkholderia cepacia. As a significant proportion of patients with CF in our community are infected with this organism, we have continued to provide lung transplantation as an option. A retrospective review was conducted of medical records of all patients with CF transplanted between March 1988 and September 1996. Fifty-six transplant procedures were performed in 53 recipients with CF between March 1988 and September 1996. Twenty-eight had B. cepacia isolated pretransplant and 25 remaining positive post-transplant. Of the 53 recipients, 19 have died (15 of 28 [54%] B. cepacia positive and 4 of 25 [16%] B. cepacia negative). B. cepacia was responsible for or involved in 14 deaths. Nine of the deaths occurred in the first 3 mo post-transplantation. One-year survival was 67% for B. cepacia positive patients and 92% for B. cepacia negative patients. Recent modifications in antimicrobial and immunosuppressive therapy since 1995 have resulted in no deaths early post-transplant in the last five patients transplanted. We conclude that early mortality in patients with CF infected with B. cepacia is significantly higher than in those not infected with B. cepacia. Modifications in post-transplant medical therapy may improve outcome.

Spectrum of Aspergillus infection in lung transplant recipients: case series and review of the literature

STUDY OBJECTIVES

(1) To define the incidence and natural history of Aspergillus colonization and infection in lung transplant recipients, and (2) to assess the impact of prophylaxis, surveillance, and therapy on the incidence and outcome of the disease.

DESIGN

Retrospective review of 133 consecutive single or bilateral lung transplantations performed at a single institution, and review of the published literature.

RESULTS

Airway colonization, isolated tracheobronchitis, and invasive pneumonia due to Aspergillus species occurred in 29%, 5%, and 8% of our series, and in 26%, 4%, and 5% of the pooled published data (all series, including ours), respectively. Greater than 50% of all diagnoses were made in the first 6 months after transplantation in both our series and the published literature. Incidence of progression from airway colonization to invasive disease was 1 in 38 in our series and 3 of 97 (3%) in the pooled published data. In patients with isolated tracheobronchitis, all 6 patients in our series and 41 of 50 patients (82%) in all published series, including ours, responded to antifungal therapy and/or surgical debridement. Among patients with invasive pneumonia or disseminated disease, however, 5 of 10 patients in our series and 26 of 64 patients (41%) in the pooled series survived their infection.

CONCLUSIONS

The role of antifungal therapy in Aspergillus airway colonization in lung transplant recipients is unclear. Data support a strategy of scheduled screening bronchoscopy followed by aggressive treatment for isolated Aspergillus tracheobronchitis in lung transplant recipients.

Complications (excluding hyperinflation) involving the native lung after single-lung transplantation: incidence, radiologic features, and clinical importance

PURPOSE

To determine the incidence, importance, and radiologic features of native lung complications after single-lung transplantation.

MATERIALS AND METHODS

Seventeen (15%) of 111 single-lung transplant recipients developed native lung complications (excluding hyperinflation) 0-58 months (mean, 17 months) after transplantation. Complaints at presentation, culture or histopathologic results, diagnostic or therapeutic procedures, and outcome were recorded. Chest radiographs (n = 17) and computed tomographic (CT) scans (n = 8) obtained at time of diagnosis were reviewed. Serial radiographs were assessed for disease progression or improvement.

RESULTS

The most common complications were infection (n = 10), caused by bacteria (n = 4), fungi (n = 4), or mycobacteria (n = 2), typically manifested as lobar or segmental opacities on chest radiographs or CT scans. Lung cancer manifested as a solitary well-circumscribed nodule (n = 1), multiple nodules (n = 1), or a hilar mass (n = 1). Five (29%) of 17 patients died of native lung complications. Seven patients underwent mediastinoscopy (n = 3), lobectomy (n = 2), thoracoscopic wedge resection (n = 2), tube thoracostomy (n = 2), or pneumonectomy (n = 1) for diagnosis or treatment.

CONCLUSION

Native lung complications occurred in 17 (15%) single-lung transplant recipients, were most commonly due to infection or lung cancer, and caused serious morbidity or mortality in 12 (71%) of 17 patients affected.

Outpatient care of the cystic fibrosis patient after lung transplantation

Lung transplantation has become an accepted treatment for respiratory failure due to cystic fibrosis (CF). Effective means of patient selection, surgical technique, immunosuppression, and post-transplant management permit survival as good as that of transplant patients with other diseases. The new lungs do not acquire the CF ion transport abnormalities but are subject to the usual post-transplant complications. CF problems in other organ systems persist and may be worsened by some of the immunosuppressive regimens. Prolonged survival increases the risk of age-related CF and other complications. Effective medical management requires expert knowledge of CF and lung transplantation and of how their problems interact, and good communications among the participating care teams.

Fluconazole in transplant recipients: options and limitations

Fluconazole is currently a first-line agent used for therapy of non-critically ill patients with candidal infection. Its efficacy, the availability of an oral formula, and its relatively low toxicity make it a very attractive drug for use in many clinical situations. The advisability of prophylaxis and empirical treatment in transplant patients is a difficult issue for the following reasons: the potential emergence of resistance to the azoles, the lack of solid data establishing its advantage over placebo and/or oral nonabsorbable antifungal agents in some of the clinical conditions encountered, its ineffectiveness against molds, and its cost. Judicious use of fluconazole where its efficacy has been well established would provide the best therapy for patients and would limit the emergence of potential pathogens. As new antifungal agents are approved for clinical use, appropriate clinical trials will need to be designed and conducted in order for clinicians to make rational decisions in selecting the most appropriate drug for the specific indication. Prophylaxis and treatment with fluconazole in various transplant situations is reviewed.

Kidney function in cyclosporine-treated paediatric pulmonary transplant recipients

BACKGROUND

Lung or heart-lung transplantation is a useful therapy in life-threatening pulmonary disorders during childhood. Cyclosporine A is a major immunosuppressive treatment but has a number of adverse effects including nephrotoxicity. There have been no reports on the long-term evolution of renal function in a large series of paediatric pulmonary transplantation recipients.

METHODS

We examined 19 patients followed up for at least 3 years after pulmonary transplantation. The mean time of follow-up was 5.36 years. Kidney function was evaluated by calculation of glomerular filtration rate (GFR) according the Schwartz formula.

RESULTS

The GFR was normal before transplantation in all patients. The short-term evolution of GFR was marked by a significant drop during the first and until the 6th month. Then, regardless of the level reached at the end of the 6th month, the GFR remained stable in all patients except one until the end of follow-up. At the end of follow-up, 31% had normal GFR, 57% had mild chronic renal failure, and 5% had advanced renal failure. Hypertension was frequent and associated with renal failure.

CONCLUSIONS

Paediatric pulmonary recipients showed evidence of long-term cyclosporine A-associated nephrotoxicity. Most of this toxicity occurred during the first 6 months.

Prevention and prophylaxis of invasive fungal sinusitis in the immunocompromised patient

Fungal infections are a leading cause of morbidity and mortality among immunocompromised patients. Invasive fungal sinusitis is a devastating complication of immunosuppression. Treatment options are limited and often ineffective, making prevention important. Measures to decrease environmental exposure, indications for antifungal prophylaxis, and limitations of current regimens are discussed.

Cystic fibrosis: usefulness of thoracic CT in the examination of patients before lung transplantation

PURPOSE

To evaluate the usefulness of thoracic computed tomography (CT) in the pre-lung transplantation examination of patients with cystic fibrosis (CF).

MATERIALS AND METHODS

Fifty-six patients (age range, 12-42 years) with CF were evaluated for possible lung transplantation from 1991 to 1997. Twenty-six of these patients underwent bilateral lung transplantation, 19 were awaiting transplantation at the time of the study, seven died before transplantation, and four were excluded for psychosocial concerns. Preoperative chest radiographic and CT findings were reviewed and correlated with clinical, operative, and pathology records.

RESULTS

In seven patients, discrete, 1-2-cm pulmonary nodules were detected at CT. Five of these patients underwent transplantation; the nodules were found to be mucous impactions. No malignancy was found in any of the patients who underwent transplantation. Pretransplantation sputum cultures grew Aspergillus fumigatus in seven patients, none of whom had radiologic findings suggestive of Aspergillus infection. Radiographic or CT findings were suggestive of mycetoma in five cases, but no such tumors were found at transplantation. The accuracies of chest radiography and CT for the detection of pleural disease in 48 hemithoraces were 81% (n = 39) and 69% (n = 33), respectively. The radiologic findings of pleural thickening did not influence the surgical approach in any patient.

CONCLUSION

Thoracic CT has little utility in the routine pre-lung transplantation examination of patients with CF.

Allergic bronchopulmonary aspergillosis in cystic fibrosis: reported prevalence, regional distribution, and patient characteristics. Scientific Advisory Group, Investigators, and Coordinators of the Epidemiologic Study of Cystic Fibrosis

OBJECTIVES

Using the large database from the Epidemiologic Study of Cystic Fibrosis (ESCF), the objectives of this study were to (1) estimate the reported prevalence of allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis (CF); (2) compare reported prevalence rates across geographic regions; (3) compare reported prevalence rates between patient subgroups based on demographic and disease characteristics; and (4) describe the ABPA group with regard to their sex, age, and disease severity.

STUDY DESIGN

All patients > or = 5 years of age enrolled in ESCF between December 1993 and May 1996 were eligible. Criteria for the diagnosis of ABPA were defined by the ESCF guidelines. Prevalence rates for ABPA were calculated, and potential risk factors for the diagnosis of ABPA were analyzed, including sex, age, pulmonary function, diagnosis of asthma, presence of wheeze, and positive respiratory culture for Pseudomonas.

RESULTS

There were 14,210 eligible patients enrolled in ESCF during this period, and ABPA was diagnosed in 281 patients (2%). Regional prevalence varied from 0.9% in the Southwest to 4.0% in the West. Increased prevalence rates occurred in female patients, the adolescent age group, and subjects with lower lung function, wheeze, asthma, and positive Pseudomonas cultures. Although most ABPA patients had evidence of airway obstruction, 10% had an FEV1 of > 100% of predicted. The rates of wheeze (17%) and asthma (30%) were lower than expected in the ABPA group.

CONCLUSIONS

This observational study found a reported prevalence rate of ABPA of 2% of CF patients in a large database. This rate was lower than the 5 to 15% rate reported in smaller studies, suggesting that ABPA is underdiagnosed in the CF population. There was wide regional variation in reported prevalence rates, which is unexplained at this time. The characteristics of the patients with ABPA and the epidemiologic risk factors for diagnosis of ABPA were described. Simplified diagnostic criteria were adapted for ESCF with the intent of increasing awareness of ABPA among the participants in this study.

Native lung pneumonectomy for invasive pulmonary aspergillosis following lung transplantation: a case report

Pulmonary aspergillosis occurs most commonly as a consequence of immunosuppression in recipients of pulmonary transplantation and is associated with a high mortality. It affects the native lung more commonly than the transplanted lung in single lung transplant patients. Infection often progresses despite aggressive medical therapy. The cornerstone of treatment of acute, semi-invasive, and invasive pulmonary aspergillosis (IPA) is medical, with intravenous amphotericin B, and oral itraconazole either as isolated or combined therapy. While newer, and more expensive liposomal forms of amphotericin B have been used to enhance tissue penetration and minimize renal toxicity, an appreciable improvement in clinical outcome has not been reported. The role of surgery in localized pulmonary aspergillus infection is well recognized, but remains undefined in immunosuppressed patients. We report a case where a pneumonectomy was performed for progressive, refractory angioinvasive aspergillosis in a lung transplant recipient whose disease progressed despite conventional antifungal therapy.

Antifungal prophylaxis during the early postoperative period of lung transplantation. Valencia Lung Transplant Group

INTRODUCTION

Fungal infections occur frequently in lung transplant patients, with the highest risk being in the early postoperative period (the initial hospitalization after lung transplantation). Aspergillus is responsible for more than half of all fungal infections, and Aspergillus has even been considered a contraindication for lung transplantation because of its difficult therapy and frequently fatal outcome. The aim of this article is to evaluate the success of an antifungal prophylaxis protocol to prevent fungal infection in the immediate postoperative period in lung transplant recipients.

MATERIAL AND METHODS

From March 1994 to March 1997, we performed 52 lung transplants in 31 men and 21 women who received antifungal prophylaxis with fluconazole, 400 mg/d, and aerosolized amphotericin B, 0.6 mg/kg/d, during the postoperative period.

RESULTS

The mean (+/- SD) postoperative period duration was 49 +/- 27.5 days. No fungal infections were observed during this period, and all patients provided negative cultures. We also found no toxicity related to antifungal drugs. The dose of cyclosporine was easily adjusted in every recipient according to blood levels so that effective immunosuppression was not compromised.

DISCUSSION

In our study, the removal of the lungs and antifungal prophylaxis with fluconazole and aerosolized amphotericin B prevented fungal infection in the postoperative period in all 52 lung transplant recipients.

Tobramycin pharmacokinetics in patients with cystic fibrosis preceding and following lung transplantation

The pharmacokinetics of tobramycin in patients with cystic fibrosis before and after lung transplantation were evaluated. Twenty-nine lung transplant recipients with cystic fibrosis who received at least one course of tobramycin pre- and posttransplantation were included in this study. Pharmacokinetic parameters (clearance, volume of distribution, elimination rate and half-life) were calculated using a one-compartment Bayesian method. Comparisons were made both between and within pre- and posttransplant periods for patients receiving multiple courses. Significant differences were noted. Clearance was decreased 40%, volume of distribution increased 20%, elimination rate increased 52%, and half-life increased 141%, respectively, posttransplant as compared to pretransplant. There were no differences within each time period between each tobramycin course. The results indicate that tobramycin pharmacokinetics are significantly altered in patients with cystic fibrosis after lung transplantation. Patients with cystic fibrosis require early and close monitoring of tobramycin after lung transplantation.

Pulmonary aspergillosis in cystic fibrosis lung transplant recipients

STUDY OBJECTIVE

To define the prevalence of colonization and infection of the lower respiratory tract (LRT) with Aspergillus in lung transplant recipients with and without cystic fibrosis (CF).

DESIGN

Retrospective review.

SETTING

Large university lung transplant center.

MATERIALS AND METHODS

The postoperative course of 31 CF and 53 non-CF double lung or double lobar transplant recipients receiving allografts from April 1991 to February 1996 was reviewed. All recipients were subjected to surveillance bronchoscopy and biopsy at predetermined intervals and when clinically indicated. BAL fluid (BALF) and biopsy material were examined by appropriate fungal culture and staining techniques. Infection was defined by the finding of tissue-invasive disease on biopsy specimens.

RESULTS

Seven of the 31 CF recipients (22%) had Aspergillus isolated from cultures of sputum prior to transplantation. Following transplantation, 15 CF recipients (48%) had Aspergillus isolated from either sputum or BALF, including 4 of the 7 recipients identified with the fungus prior to transplantation. By contrast, 21 of the 53 non-CF recipients (40%) had Aspergillus isolated from the LRT following transplantation, none having had the fungus isolated prior to transplantation. The prevalence of Aspergillus did not differ between these groups (p = 0.51). Infections with Aspergillus occurred in 4 of the CF recipients (27%) and did not differ from the 3 infections (14%) identified in the non-CF recipients (p = 0.36). However, three of the four infections in the CF recipients involved the healing bronchial anastomosis and occurred prior to postoperative day 60. All three of these recipients had Aspergillus preoperatively. Postoperative infection was more common in the CF recipients having Aspergillus preoperatively than in those CF recipients without preoperative Aspergillus (p = 0.02).

CONCLUSIONS

Isolation of Aspergillus from the LRT following double lung transplantation is common and generally not associated with tissue-invasive disease. Those CF recipients with Aspergillus isolated in cultures of sputum preoperatively are at risk for postoperative infections with this agent. The healing bronchial anastomosis is particularly vulnerable.

Lung transplantation for cystic fibrosis

Lung transplantation currently stands as the only therapeutic option that carries the potential to restore patients with advanced cystic fibrosis to a more normal state of health. Nonetheless, the procedure carries significant risk and median survival following transplantation is only 5 years. This article discusses the currently achievable outcomes and the common short-comings of transplantation. Strategies to optimize outcomes through appropriate patient selection, use of living donors, and novel research initiatives are discussed.

Lung transplantation for cystic fibrosis--a single center experience over 8 years

OBJECTIVE

Colonization of the lung and mediastinal lymph nodes with multi-resistant bacteria, diabetes and malnutrition represent potential risk factors for lung transplantation in cystic fibrosis. We therefore reviewed our experience in this patient population.

METHODS

Between December 1988 and March 1997, 219 lung and heart-lung transplantations were performed at our institution. Of these, 39 procedures were done in 35 patients with cystic fibrosis. All candidates (mean age 26 years) were oxygen dependent (preoperative mean PO2: 44.8 +/- 9.1 Torr, preoperative mean PCO2: 53.4 +/- 10.5 Torr, one patient on respirator). Of the primary operations, 34 were performed as bilateral sequential lung transplants, one as a heart-lung transplantation.

RESULTS

Mean duration on respirator for survivors was 3.1 (1-12) days, mean ICU and hospital stay were 4.7 (1-13) and 28 (12-79) days, respectively. The 3-month mortality rate was 5.7% (two patients died due to acute graft failure on days 36 and 73). Other causes of death in the follow-up were cerebral bleeding (one patient) and chronic graft failure (three patients). The survival rates were 91% at 1 year, 83% at 3 years and 76% at 5 years. In eight patients, a bronchiolitis obliterans syndrome (BOS) developed (in four cases grade 3). The freedom of BOS (grade 1 or more) at 1, 3 and 5 years was 87, 79 and 55%, respectively. Four retransplantations were performed. Of the 29 patients alive, only seven are physically limited.

CONCLUSION

Bilateral lung transplantation for cystic fibrosis allows for acceptable early- and long-term results. Postoperative survival is not impaired by infection, diabetes and malnutrition. Long-term functional outcome seems to be comparable to lung transplantation in patients without infectious pulmonary disease.