Household proximity to water and nontuberculous mycobacteria in children with cystic fibrosis.

BACKGROUND: Nontuberculous mycobacteria (NTM) have a particular affinity for patients with cystic fibrosis (CF). Recent studies suggest a possible relationship between acquiring NTM and the level of environmental water in a given area. We sought to determine if there is an association between household proximity to water and NTM in children with CF. MATERIALS AND METHODS: An IRB-approved retrospective chart review was completed on 150 children with CF in Florida. Inclusion criteria required regular follow-up, at least two acid-fast bacilli cultures, and a consistent home address over a 3-year period. The distance from each patient's home to the nearest body of water was measured using ArcMap®, a Geographic Information System, and the mean distance to water for NTM-positive and NTM-negative groups were compared. A stepwise backwards logistic regression was used to evaluate for predictors of NTM-positivity. RESULTS: Of the 150 CF patients, 65 met inclusion criteria and 21 (32.3%) tested positive for NTM. Comparison of the mean distance to water for NTM-positive versus NTM-negative groups revealed a cutoff of 500 meters. On the logistic regression, CF patients who lived within 500 meters of water were 9.4 times more likely to acquire NTM (P = 0.013). Other significant predictors included a history of Aspergillus fumigatus (OR 7.9, P = 0.011) and recent history of Pseudomonas aeruginosa (OR 2.5, P = 0.007). CONCLUSIONS: In the regions studied, children with CF who live closer to water are more likely to acquire nontuberculous mycobacteria. Future studies in other geographic areas are needed to determine if these results are generalizable. Pediatr Pulmonol. 2017;52:324-330. © 2016 Wiley Periodicals, Inc.

Lung transplantation for childhood diffuse lung disease.

BACKGROUND: Pediatric diffuse lung diseases comprise a heterogeneous group of rare lung disorders which may lead to end stage lung disease and referral for lung transplantation. Previous studies are limited by small numbers of patients with specific forms of diffuse lung disease. Children with all forms of diffuse lung disease who underwent lung transplantation at two pediatric centers were evaluated in terms of several pre- and post-transplant factors and compared to children with other end stage lung disorders. METHODS: A retrospective chart review was performed on all patients transplanted between October 1, 2002 and June 15, 2007 at Texas Children's Hospital and St. Louis Children's Hospital. Multiple pre-transplant characteristics and post-transplant morbidities and mortality were compared between diffuse lung disease, cystic fibrosis, and pulmonary vascular disease groups. RESULTS: There were 31 diffuse lung disease (DLD), 57 cystic fibrosis (CF), and 16 pulmonary vascular disease (PVD) patients included in our analysis. Patients with DLD had significantly higher pre-transplant morbidity including lower percent predicted of forced expiratory volume in first second (P = 0.013) and more patients with pulmonary hypertension (P = 0.001) and hypercapnia (P = 0.031). Compared to CF patients, more DLD and PVD patients required invasive ventilation (P = 0.001) and care in the pediatric intensive care unit (P = 0.001). After transplant, there was a difference among the three groups with regards to number of acute allograft rejections but statistical limitations preclude knowing between which group the difference lies. A difference in time to bronchiolitis obliterans was found between the PVD and CF groups but not when compared to the DLD patients. The three groups had similar time to post-transplant lymphoproliferative disease, rate of infections, and survival. CONCLUSION: Lung transplantation is as successful for patients with end stage diffuse lung disease as compared to other lung transplant candidates.

Decline in 25% to 75% forced expiratory flow as an early predictor of chronic airway rejection in pediatric lung transplant recipients.

BACKGROUND: Bronchiolitis obliterans (BO) is the major obstacle to long-term lung allograft viability. Its clinical correlate, BO syndrome (BOS), is defined as a decline of at least 20% in forced expiratory volume in 1 second (FEV(1)) from baseline. BOS is often diagnosed after significant organ dysfunction has occurred. Because BO is a small-airways disease, we hypothesized that a 20% decline in the 25% to 75% forced expiratory flow (FEF(25-75)) from baseline should occur before a decline in FEV(1) and should predict progression to BOS with high sensitivity and specificity. METHODS: Pulmonary function tests and records of pediatric lung transplantation patients at Texas Children's Hospital from 2002 to 2007 were reviewed. Declines in FEV(1) and FEF(25-75) from the best post-transplant baseline values were recorded and analyzed. Sensitivity, specificity, and positive and negative predictive values were calculated. RESULTS: Thirty-one patients were eligible for the study. In 11 BOS patients, the mean±standard deviation number of days from transplant until a 20% decline in FEV(1) was 896.5±400 compared with 728.0±475 (p = 0.022) until a 20% decline in FEF(25-75) was reached. The sensitivity, specificity, and positive predictive and negative predictive values of a 20% reduction in FEF(25-75) in determining BOS were 100%, 90.0%, 84.6%, and 100%, respectively. CONCLUSIONS: All patients who developed BOS had a decline in FEF(25-75) at or before the decline in FEV(1). The reduction in FEF(25-75) occurred statistically significantly earlier than the decline in FEV(1), by an average of 168.5 days. This decline in FEF(25-75) was also highly sensitive and specific for the diagnosis of BOS.

Two decades of pediatric lung transplant in the United States: have we improved?

OBJECTIVE: Since 1988, approximately 1100 pediatric lung transplants have been performed worldwide with consistent improvement in survival. Similarly, survival for pediatric heart transplant has increased over the years; however, in this cohort improvement in survival is exclusively a result of increased early (1-year) survival. To observe if this same phenomenon exists in pediatric lung transplants, the United Network for Organ Sharing database was analyzed to evaluate and characterize how pediatric lung transplant survival has changed in the past 2 decades. METHODS: The United Network for Organ Sharing database was queried for patients aged 18 years or less who underwent lung transplantation from May 1988 to May 2008. Analysis included 959 pediatric lung transplants. RESULTS: Age groups were infants (≤1 years) (n = 106 [11%]), children (2-12 years) (n = 299 [31%]), and adolescents (≥13 years) (n = 554 [58%]). A total of 546 (57%) were girls. Kaplan-Meier survival was significantly better in the late era (2002-2008) than in all other eras (1988-1994 and 1995-2001) (P < .05). The half-life for graft has increased significantly over the eras (early, 2.2 years; mid, 3.3 years; and late, 3.8 years). Conditional 1-year survival (ie, mid to late survival) was not significantly different (P = .3) among the eras. Gender, age, diagnosis, prolonged ischemic time, and cytomegalovirus mismatch did not significantly affect overall patient or graft survival. Chronic preoperative steroid dependence (P = .02), preoperative ventilatory dependence (P < .001), and retransplantation (P = .02) were associated with decreased survival. CONCLUSIONS: Survival in pediatric lung transplant has increased significantly over the years, but this improvement primarily reflects improvement in early survival. Survival in pediatric lung transplant after the first posttransplant year has not changed in more than 2 decades.

Serum KL-6 level and the development of bronchiolitis obliterans syndrome in lung transplant recipients.

KL-6 is a glycoprotein expressed by pulmonary epithelial cells, and its serum level has been used as a marker of disease activity in a variety of respiratory illnesses. Previously, we showed that KL-6 was elevated in lung transplant recipients diagnosed with BOS. In this study, we followed serum KL-6 levels and lung functions prospectively in lung transplant recipients who were within the first five-yr post-transplant and had no evidence of BOS at the time of study entry. Mean peak KL-6 levels were 596.16 ± 309.32 U/mL in the nine recipients who developed BOS compared to 352.41 ± 140.68 in 36 recipients who did not (p = 0.05). Six of the nine patients with BOS had an absolute rise in KL-6 above baseline level >200 U/mL compared to two of the 37 who had the same increase in KL-6 but did not develop BOS. Using the 200 U/mL elevation of KL-6 from baseline as a threshold for a positive test would produce a sensitivity of 67%, specificity of 95%, PPV of 75%, and a NPV of 92%. In addition, mean KL-6 levels of patients during acute rejection were not significantly elevated compared to the prerejection mean KL-6 levels (p = 0.71). We conclude that serum KL-6 is a relatively specific marker of BOS in lung transplant recipients.

Minimal acute rejection in pediatric lung transplantation--does it matter?

In adult lung transplantation, a single minimal AR episode is a significant predictor of BOS independent of other factors. However, the significance of single minimal AR episodes in children is unknown. A retrospective, multi-center analysis was performed to determine whether isolated single AR episodes are associated with an increased BOS risk in children. Risk factors for BOS, death, or re-transplantation, and a combined outcome of BOS, death, or re-transplantation were assessed. Original data included 577 patients (<21 yr of age). A total of 383 subjects were eligible for the study. Fifteen percent of patients developed BOS, and 13% of patients either died or underwent re-transplant within one-yr post-transplant. In the multivariable survival model for time to BOS, there was no significant risk to developing BOS after a single minimal AR (A1) episode (HR 1.7, 95% CI 0.64-4.8; p=0.28). Even after a second minimal AR episode, no significant risk for BOS was appreciated. However, a single episode of mild AR (A2) was associated with twice the risk of BOS within one-yr post-transplant. In this select cohort, a single minimal AR episode was not associated with an increased risk for BOS within one yr following lung transplantation, in contrast to previous reports in adults.

IgA nephropathy presenting with renal failure and pulmonary hemorrhage.

Pulmonary renal syndromes are unusual, but frequently life-threatening manifestations of a distinct group of disorders in the pediatric age group. Although IgA nephropathy is a common cause of hematuria, it is an extremely rare cause of pulmonary renal syndrome, causing high mortality, and has mostly been reported in adult patients. We describe the youngest patient with this presentation reported to date, a 14-year-old male, who presented with end stage renal disease and pulmonary hemorrhage and was found to have IgA nephropathy by renal biopsy and pulmonary capillaritis by open lung biopsy. His lung disease was successfully treated with immunosuppressive medications. Despite this being a rare manifestation of IgA nephropathy, clinicians need to be aware of this presentation as it is potentially fatal, but amenable to aggressive immunosuppression.

Cytomegalovirus immunoglobulin decreases the risk of cytomegalovirus infection but not disease after pediatric lung transplantation.

BACKGROUND: Cytomegalovirus (CMV) has been associated with morbidity, including chronic allograft rejection, in transplant recipients. Data from adult centers suggests that CMV hyperimmune globulin (CMVIG) and ganciclovir together are superior in preventing CMV viremia than ganciclovir alone. METHODS: A retrospective review of pediatric lung transplant recipients at 14 sites in North America and Europe was conducted to evaluate the effect of adding cytomegalovirus immunoglobulin (CMVIG) prophylaxis to at least 3 weeks of intravenous ganciclovir therapy in pediatric lung transplant recipients. Data were recorded for the first year after transplantation. Associations between time to CMV and risk factors, including CMVIG use, were assessed by multivariable Cox proportional hazards models. RESULTS: Of 599 patients whose records were reviewed, 329 received at least 3 weeks of ganciclovir, with 62 (19%) receiving CMVIG. CMVIG was administered more frequently with CMV donor-positive/recipient-negative serostatus (p < 0.05). In multivariable models, patients who did not receive CMVIG as part of their prophylaxis were 3 times more likely to develop CMV infection (hazard ratio, 3.4; 95% confidence interval, 1.2-9.5) independent of CMV serostatus. However, CMVIG administration was not associated with decreased risk of episodes of CMV disease. Receipt of CMVIG was not associated with decreased risks of post-transplant morbidities (acute rejection, respiratory viral infection or early bronchiolitis obliterans) or morbidity within the first year after pediatric lung transplantation. CONCLUSION: The use of CMVIG in addition to antiviral prophylaxis in pediatric lung transplantation requires further evaluation.

Fungal infections in pediatric lung transplant recipients: colonization and invasive disease.

BACKGROUND: The purpose of this study was to evaluate the epidemiology and investigate the impact of colonization and pulmonary fungal infections (PFIs). METHODS: In this investigation we performed a retrospective analysis of 55 pediatric lung transplant recipients from 2002 to 2007 at a single institution. Associations between risk factors and time to post-transplant colonization, PFI, and other outcomes were assessed using Cox proportional hazard models. RESULTS: Although 29 patients had positive pre-transplant colonization, 33 (60%) were colonized post-transplant and 20% (11 subjects) developed proven or probable PFI. In a multivariate model, post-transplant fungal colonization was associated with older age (hazard ratio [HR] 2.9, 95% confidence interval [CI] 1.1 to 7.6), cytomegalovirus (CMV) prophylaxis (HR 5.6, 95% CI 1.3 to 24.6) and respiratory viral infection prior to fungal colonization (HR 2.9, 95% CI 1.0 to 8.3). CONCLUSION: Neither fungal colonization nor PFI was associated with the development of chronic allograft rejection or death.

Cerebral aspergillosis caused by Aspergillus granulosus.

Disseminated disease by Aspergillus granulosus has been reported only once previously in a cardiac transplant recipient. We report a fatal central nervous system infection in a lung transplant recipient. Key features of this species in the section Usti include growth at 37 degrees C and large, randomly spaced aggregates of variably shaped Hülle cells.

Management of the pediatric organ donor to optimize lung donation.

Lung transplantation in childhood is a highly specialized clinical practice confined to a few centers around the world. Organ availability remains an important limiting factor in extending the application of this procedure to more infants, children and adolescents. The lungs are the organ most vulnerable to injury, infection and dysfunction among transplantable organs in the brain dead deceased donor. In this manuscript, we review the pathophysiology of the most common and important disease states that affect the lungs in potential donors. Furthermore, we herein provide recommendations for optimal management of the pediatric organ donor with an emphasis on strategies to improve the opportunity for the lungs to be placed in candidates on the transplant list.

The risk, prevention, and outcome of cytomegalovirus after pediatric lung transplantation.

BACKGROUND: A retrospective review of pediatric lung transplant recipients at 14 centers in North America and Europe was conducted to characterize the epidemiology and the risk factors for cytomegalovirus (CMV) and to explore the impact of preventative antiviral therapy. METHODS: Data were recorded for 1 year posttransplant. Associations between CMV and continuous and categorical risk factors were assessed using Wilcoxon rank sum and chi-square tests, respectively. Associations between time to CMV and risk factors or survival were assessed by multivariable Cox proportional hazards models. RESULTS: Within 12 months posttransplant, 172 of 577 subjects (29.8%) developed 218 CMV episodes (90 asymptomatic infection, 25 syndrome, and 103 disease). Forty-one subjects developed more than one episode of CMV. Donor or recipient CMV seropositivity was associated with increased risk of CMV episodes. Except for decreased prophylaxis in CMV D-/R- subjects, duration of prophylaxis did not vary by D/R serostatus. For CMV D+ subjects, not being on prophylaxis at the time of CMV episode increased the risk of CMV (D+/R+ hazard ratio 3.5, 95% confidence interval 1.4-8.4; D+/R- 1.9, 1.02-3.7). CMV was associated with increased mortality within the first posttransplant year among those with donor or recipient CMV seropositivity (hazard ratio 2.0: 95% confidence interval 1.1-3.6; P=0.024). CONCLUSIONS: CMV remains a serious complication after pediatric lung transplant, and the impact of prophylaxis is complex.

Post-transplant lymphoproliferative disease in pediatric lung transplant recipients: recent advances in monitoring.

To investigate the clinical validity of newer diagnostic tests such as monitoring of EBVqPCR and lymphocyte function assay ImmuKnow in helping to diagnose PTLD in pediatric lung transplant recipients. Single-center, retrospective case-control study. CsA trough levels, EBVqPCR and ImmuKnow (Cyclex Inc., Columbia, MD, USA) levels were measured serially as part of routine care. Re-transplant patients and patients who did not reach 12 months post-transplant at the time of analysis were excluded. Twenty-seven patients met the inclusion criteria. The study group consisted of seven patients who developed PTLD, five of which were EBV- recipients who received EBV+ lungs. The rest of the eligible patients served as controls. Median time to develop PTLD was 273 days (range: 166-343). One, two, three, six, and nine months after transplant, mean (+/-s.d.) CsA trough whole blood levels (ng/mL) were not different between the two groups: 378 +/- 38, 390 +/- 52, 402 +/- 89, 359 +/- 42, and 342 +/- 115, vs. 416 +/- 105, 347 +/- 64, 337 +/- 78, 333 +/- 86, and 281 +/- 54 [PTLD vs. no-PTLD, respectively (p > 0.05 for all time points)]. Mean (+/-s.d.) EBVqPCR levels (copies/mL) measured at three, six, and nine months post-transplant were significantly elevated in PTLD group compared to no-PTLD group: 84 +/- 99, 3384 +/- 7428 and 839 +/- 1444 vs. 9 +/- 26, 8 +/- 36 and 32 +/- 136, respectively (p < 0.05 for all time points). Mean (+/-s.d.) ImmuKnow levels (ATP ng/mL) at three, six, and nine months post-transplant were significantly lower in the PTLD group when compared with no-PTLD group: 144 +/- 67, 137 +/- 110, and 120 +/- 153 vs. 290 +/- 161, 300 +/- 162, and 293 +/- 190, respectively (p < 0.05 for all time points). Close monitoring of EBV viral load by qPCR and the degree of immunosuppression via ImmuKnow may guide physicians to reach the diagnosis of PTLD early.

Hypogammaglobulinemia: Incidence, risk factors, and outcomes following pediatric lung transplantation.

Infection is the leading cause of morbidity and mortality in the first year following lung transplantation. HG after adult lung transplantation has been associated with increased infections and hospitalization as well as decreased survival. The purpose of this study is to define the incidence, risk factors, and outcomes of HG in the first year following pediatric lung transplantation. A retrospective review of all lung transplant recipients at a single pediatric center over a four-yr period was performed. All serum Ig levels drawn within one yr of transplantation were recorded. An association between HG during the first year after transplantation and age, race, gender, diagnosis leading to transplantation and clinical outcomes including hospitalization, infections requiring hospitalization, viremia, fungal recovery from BAL lavage, and mortality was sought. HG was defined using age-based norms. Fifty-one charts were reviewed. Mean (+/-s.d.) post-transplantation levels for IgG, IgA, and IgM were 439.9 +/- 201.3, 82.3 +/- 50.2, and 75.2 +/- 41.4 mg/dL, respectively. HG was present in 48.8%, 12.2%, and 17.1% of patients for IgG, IgA, and IgM, respectively. Patients with HG for IgG were older (14.3 +/- 3.8 vs. 9.2 +/- 5.4 yr; p < 0.01). IgA and IgM HG were associated with invasive aspergillosis (p < 0.01 and p = 0.05, respectively). IgG and IgM levels inversely correlated with bacterial infections and hospital days, respectively (p < 0.01, p < 0.05). HG is a frequent complication following pediatric lung transplantation. Low Ig levels are associated with increased infections and hospital stay.

Pulmonary alveolar proteinosis caused by deletion of the GM-CSFRalpha gene in the X chromosome pseudoautosomal region 1.

Pulmonary alveolar proteinosis (PAP) is a rare lung disorder in which surfactant-derived lipoproteins accumulate excessively within pulmonary alveoli, causing severe respiratory distress. The importance of granulocyte/macrophage colony-stimulating factor (GM-CSF) in the pathogenesis of PAP has been confirmed in humans and mice, wherein GM-CSF signaling is required for pulmonary alveolar macrophage catabolism of surfactant. PAP is caused by disruption of GM-CSF signaling in these cells, and is usually caused by neutralizing autoantibodies to GM-CSF or is secondary to other underlying diseases. Rarely, genetic defects in surfactant proteins or the common beta chain for the GM-CSF receptor (GM-CSFR) are causal. Using a combination of cellular, molecular, and genomic approaches, we provide the first evidence that PAP can result from a genetic deficiency of the GM-CSFR alpha chain, encoded in the X-chromosome pseudoautosomal region 1.

Increased mortality after pulmonary fungal infection within the first year after pediatric lung transplantation.

BACKGROUND: Risk factors, morbidity and mortality from pulmonary fungal infections (PFIs) within the first year after pediatric lung transplant have not previously been characterized. METHODS: A retrospective, multicenter study from 1988 to 2005 was conducted with institutional approval from the 12 participating centers in North America and Europe. Data were recorded for the first post-transplant year. The log-rank test assessed for the association between PFI and survival. Associations between time to PFI and risk factors were assessed by Cox proportional hazards models. RESULTS: Of the 555 subjects transplanted, 58 (10.5%) had 62 proven (Candida, Aspergillus or other) or probable (Aspergillus or other) PFIs within the first year post-transplant. The mean age for PFI subjects was 14.0 years vs 11.4 years for non-PFI subjects (p < 0.01). Candida and Aspergillus species were recovered equally for proven disease. Comparing subjects with PFI (n = 58) vs those without (n = 404), pre-transplant colonization was associated with PFI (hazard ratio [HR] 2.0; 95% CI 0.95 to 4.3, p = 0.067). Cytomegalovirus (CMV) mismatch, tacrolimus-based regimen and age >15 years were associated with PFI (p < 0.05). PFI was associated with any prior rejection higher than Grade A2 (HR 2.1; 95% CI 1.2 to 3.6). Cystic fibrosis, induction therapy, transplant era and type of transplant were not associated with PFI. PFI was independently associated with decreased 12-month survival (HR 3.9, 95% CI 2.2 to 6.8). CONCLUSIONS: Risk factors for PFI include Grade A2 rejection, repeated acute rejection, CMV-positive donor, tacrolimus-based regimen and pre-transplant colonization.

Pediatric lung transplantation: a therapy in its adolescence.

Pediatric lung transplant was born at the University of Toronto as an extension of the pioneering work of Cooper and Patterson in adult lung transplant in the 1980s. Through the 1990s, the field of pediatric lung transplantation grew with clinical outcomes in the largest centers being comparable to those in adult lung transplantation. For children and adults, the largest obstacle to long-term survival remains chronic allograft rejection secondary to the development of bronchiolitis obliterans, for which little advancement has been made in prevention or treatment. While transplantation has become accepted therapy for end-stage lung disease in adults, pediatric lung transplant has been less widely embraced for multiple reasons, such as adolescent non-compliance and the investment required in developing freestanding pediatric lung transplant centers. Another factor limiting pediatric lung transplant has been the paucity of suitable donor lungs. In 2002, Texas Children's Hospital and the Baylor College of Medicine successfully collaborated in developing an active and successful pediatric lung transplant program. Through our own work and an international collaborative of pediatric transplant pulmonologists and surgeons, we are hoping to move the field of pediatric lung transplant out of its "adolescence" into adulthood.

Lung transplantation and survival in children with cystic fibrosis: solid statistics--flawed interpretation.

In their provocative paper, "Lung transplantation and survival in children with cystic fibrosis," Liou and colleagues state that "Prolongation of life by means of lung transplantation should not be expected in children with cystic fibrosis. A prospective, randomized trial is needed to clarify whether and when patients derive a survival and quality of life benefit from lung transplantation." Unfortunately, that conclusion is not supportable. Liou's dataset introduced bias against transplantation by using covariates obtained well before the time of transplant (when predicted survival was good) and having a cohort with lower than expected post-transplant survival than reported elsewhere. The calculated hazard ratios are based on factors that may have changed between listing and transplant, and do not reflect true benefit on a patient by patient basis. The findings of the study are contrary to other studies using similar methods. Finally, recent changes in US lung transplant allocation policy may have made the study findings moot. In contrast to Liou's suggestion to perform an ethically and logistically challenging randomized trial to verify the benefit of lung transplantation, a research agenda is recommended for pediatric lung transplantation for cystic fibrosis that focuses on developing strategies to continually reassess and maximize quality of life and survival benefit.