Parental perceptions of body weight and appetite in infants and toddlers with cystic fibrosis

Nutritional status has clinical relevance and is a target of guidance to parents of children with cystic fibrosis (CF). Growth is routinely monitored in CF clinics but there is no standardized way of assessing appetitive behaviors or parents' perceptions of their children's appetite. Greater understanding of these factors could improve clinical guidance regarding parent feeding behaviors. We therefore aimed to assess parent perceptions of child weight, and parent reports of child appetite using the Baby Eating Behavior Questionnaire (BEBQ), in a sample of infants and toddlers with CF, compared with a community sample. We additionally assessed relationships of parent perceptions of child weight with parent feeding behaviors in the sample with CF. Anthropometric and questionnaire data were collected for 32 infants and toddlers with CF, as well as 193 infants and toddlers drawn from RESONANCE, a community cohort study. Parents perceived children with CF to be lower in weight than their actual weight, to a greater extent than was evident in the community sample. Parents who perceived their children with CF to be underweight vs. right weight reported greater slowness in eating on the BEBQ. Parents perceived children with CF to have greater slowness in eating and lower enjoyment of food, compared to parents of children in the community sample, independent of sample differences in child weight, age, and sex. Our results demonstrate the potential utility of the BEBQ in a clinical sample and suggest it may be helpful for clinicians to assess parents' perceptions of their child's weight and appetite to promote a fuller understanding of the child's nutritional status, facilitate appropriate feeding behaviors and alleviate unnecessary concerns.

Neurodevelopmental Outcomes in Children After Fetoscopic Endoluminal Tracheal Occlusion for Severe Congenital Diaphragmatic Hernia: Results From a Multidisciplinary Clinic

BACKGROUND

We compared early neurodevelopmental morbidity in young children with severe CDH who underwent FETO to those without fetal therapy.

METHODS

We conducted a prospective study of severe CDH patients undergoing FETO (n = 18) at a single North American center from 2015 to 2021 (NCT02710968). Outpatient survivors (n = 12) were evaluated by a multidisciplinary team and compared to expectantly managed CDH patients. Neurodevelopmental outcomes were assessed using the Capute Scales [Clinical Linguistic and Auditory Milestone Scales (CLAMS) and Cognitive Adaptive Test (CAT)], with a developmental quotient (DQ) < 85 indicative of at-risk for delay.

RESULTS

At one year, 58% (n = 7) of FETO patients underwent evaluation, with notable concern for language delay (CLAMS median DQ, 80.1 [interquartile range, 67.6-86.7]). FETO scores improved by 24-months, whereas high severity/non-FETO scores declined [CLAMS median DQ (Difference in DQ), 92.3 (+12.2) vs. 77.1 (-13.4), respectively; p = 0.049]. On the initial CAT, FETO patients had concern for visual motor and problem-solving delays, with a median DQ of 81.3 (62.1-89.4). At 24-months, FETO patients had improving scores [Median CAT DQ, 90.8 (+9.5)], whereas high severity/non-FETO [87.5 (-3.0), p = 0.28] had declining scores.

CONCLUSION

These initial data suggest that FETO is associated with favorable neurodevelopmental outcomes at 24-months compared to severe CDH under expectant management.

LEVEL OF EVIDENCE

III.

Morbidity in children after fetoscopic endoluminal tracheal occlusion for severe congenital diaphragmatic hernia: Results from a multidisciplinary clinic

BACKGROUND

Although fetoscopic endoluminal tracheal occlusion (FETO) was recently shown to improve survival in a multicenter, randomized trial of severe congenital diaphragmatic hernia (CDH), morbidity outcomes remain essentially unknown. The purpose of this study was to assess long-term outcomes in children with severe CDH who underwent FETO.

METHODS

We conducted a prospective study of severe CDH patients undergoing FETO at an experienced North American center from 2015-2021 (NCT02710968). This group was compared to a cohort of non-FETO CDH patients with severe disease as defined by liver herniation, large defect size, and/or ECMO use. Clinical data were collected through a multidisciplinary CDH clinic. Statistics were performed with t-tests and Chi-squared analyses (p≤0.05).

RESULTS

There were 18 FETO and 17 non-FETO patients. ECMO utilization was 56% in the FETO cohort. Despite significantly lower median observed/expected lung-to-head ratio (O/E LHR) in the FETO group, [FETO: 23% (IQR:18-25) vs. non-FETO: 36% (IQR: 28-41), p<0.001], there were comparable survival rates at discharge (FETO: 78% vs. non-FETO: 59%, p = 0.23) and at 5-years (FETO: 67% vs. non-FETO: 59%, p = 0.53) between the two cohorts. At a median follow up of 5.8 years, metrics of pulmonary hypertension, pulmonary morbidity, and gastroesophageal reflux disease improved among patients after FETO. However, most FETO patients remained on bronchodilators/inhaled corticosteroids (58%) and were feeding tube dependent (67%).

CONCLUSIONS

These North American data show that prenatal tracheal occlusion, in conjunction with a long-term multidisciplinary CDH clinic, is associated with acceptable long-term survival and morbidity in children after FETO.

LEVEL OF EVIDENCE

Level III.

Rechallenge of Elexacaftor/Tezacaftor/Ivacaftor After Skin Rash in Two Pediatric Patients

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have revolutionized care for patients with cystic fibrosis (CF). The triple combination product elexacaftor/tezacaftor/ivacaftor is a highly effective CFTR modulator that is generally well tolerated. However, in clinical trials of pediatric and adult patients, 4% to 12% developed rash after initiation of therapy. Few reports have described approaches to management of this adverse effect. In this report, we describe 2 children with CF who developed a pruritic, maculopapular rash after initiating elexacaftor/tezacaftor/ivacaftor. These patients were successfully rechallenged after rash resolution with a practical titration schedule.

Real World Experience of Pseudomonas aeruginosa Eradication at an Urban Pediatric Cystic Fibrosis Center

OBJECTIVES

Clinical practice guidelines for eradication of Pseudomonas aeruginosa (PA) in patients with cystic fibrosis (CF) have been established, but current studies have not assessed how these guidelines translate into clinical practice. This study aimed to characterize the real-world eradication strategies, eradication rates, and microbiologic outcomes of patients with first acquisition of PA at an urban pediatric CF center.

METHODS

The Cystic Fibrosis Foundation Patient Registry was used to identify patients with CF who received care between January 2014 and September 2018 and had PA isolated from an airway culture. Patients were included if they had a first positive PA culture or the first positive culture in 2 years. Data regarding patient demographics, timing and results of airway cultures, and treatment regimens were collected.

RESULTS

Over a 3.75-year period, 75 patients had an initial positive culture for PA. Of those patients, 74 (98.7%) received eradication treatment. Tobramycin inhalation solution (TIS) monotherapy was the most common regimen prescribed (52.7%) followed by TIS plus an oral fluoroquinolone (28.4%) (TIS + FQ). Of those treated, 62 (83.8%) patients had eradication of PA at first follow-up culture (median, 58 days; IQR, 49-77 days). Eradication rates (84.6% vs 76.2%, p = 0.421) and times to recurrence (6.37 months vs 5.1 months, p = 0.726) were comparable between TIS and TIS + FQ cohorts.

CONCLUSIONS

The eradication rate for PA in clinical practice is similar to that published in the literature. Consistent with published guidelines, these microbiologic outcomes do not support the addition of an oral FQ to TIS for initial PA eradication.

Changes in mucociliary clearance over time in children with cystic fibrosis

OBJECTIVES

(a) To quantify changes in mucociliary clearance (MCC) over time in children with cystic fibrosis (CF) and the relationship between MCC and rate of infection with Pseudomonas aeruginosa (PA); (b) to determine the impact of MCC on the evolution of CF lung disease; and (c) to explore the role of mucus composition as a determinant of MCC.

METHODS

Children with CF, who had previously undergone an MCC measurement (visit 1), underwent the following tests 3 to 10 years later: (a) second MCC measurement (visit 2); (b) multiple breath washout to assess ventilation inhomogeneity, expressed as lung clearance index (LCI); (c) high resolution computed tomography lung scan (HRCT); and (d) induced sputum test. Number of PA + cultures/year between visits was documented and mucus dry weight was quantified in the children and adult controls.

RESULTS

Nineteen children completed both visits. Median time between visits was 4.6 years. Clearance declined 30% between visits. Lower MCC on visit 2 was associated with more PA+ cultures/year between visits. Lower MCC values on visit 1 were associated with higher LCI values and higher HRCT scores on visit 2. Mucus dry weight was significantly higher in children with CF compared with controls. Higher dry weights were associated with lower MCC.

CONCLUSIONS

Mucociliary clearance declines significantly over time in children with CF. The decline is associated with PA infection rate and is affected by mucus composition. Children with early slowing of MCC appear to be at risk for developing ventilation inhomogeneity and parenchymal lung damage when they are older.

A longitudinal assessment of non-invasive biomarkers to diagnose and predict cystic fibrosis-associated liver disease

BACKGROUND & AIMS

A practical, inexpensive, and non-invasive biomarker of liver fibrosis is needed as a reliable screening test for cystic fibrosis-associated liver disease (CFLD). Studies have shown the utility of AST to Platelet Ratio Index (APRI), fibrosis index based on 4 factors (FIB-4), and gamma-glutamyl transferase (GGT) as good biomarkers for identifying CFLD. The goal of the study was to evaluate the effectiveness of APRI, FIB-4, AST/ALT ratio, platelet count, GGT, and GGT platelet ratio (GPR) in predicting CFLD development.

METHODS

Data was collected from CF Foundation Patient Registry for patients aged 3-21 years at Johns Hopkins from January 1, 2002 to December 31, 2014. Collected data included demographic characteristics, presence of splenomegaly, hepatomegaly, ascites, and variceal bleeding, AST, ALT, GGT, platelet count, and FEV₁. The sensitivity and specificity of each biomarker were analyzed and reported by the area under receiver operating characteristic (AUROC) curve.

RESULTS

By the end of the study, 144 "healthy" CF, 12 CFLD, 19 CF-associated pulmonary disease (CFPD), and 4 CFLD with CFPD cases were identified. APRI scores were higher in CFLD, 0.85 versus 0.28 in "healthy" CF and 0.23 in CFPD groups (p<0.001). GPR had the highest AUROC curve at 0.91.

CONCLUSIONS

GPR, GGT, APRI score, and platelet count were potentially useful biomarkers while FIB-4 did not predict CFLD development. Cost-effectiveness studies are needed to analyze the utility of these biomarkers in clinical practice.

Ivacaftor for the treatment of cystic fibrosis in children under six years of age

Introduction: Cystic fibrosis (CF) results from aberrant ion transport due to abnormalities or absence of the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride transporter that resides on the apical surface of epithelial cells. A novel class of medications, known as CFTR modulators, specifically target the abnormal protein.Areas covered: Ivacaftor increases the open probability of CFTR located on the cell surface, leading to enhanced chloride transport, and has been shown to improve lung function, weight, and quality of life. We reviewed the sentinel studies that lead to the approval of the use of ivacaftor in people with CF age six months and older with at least one CFTR gene mutation that is responsive to ivacaftor based on clinical trial and/or in vitro data. Children with CF have the greatest potential to benefit from CFTR modulator therapy when it is initiated prior to the development of permanent damage; however, challenges remain regarding use of ivacaftor in the youngest pediatric population.Expert opinion: Ivacaftor is safe and effective CFTR modulator that can be prescribed in children over six months of age with at least one CFTR gene mutation that is responsive to ivacaftor.

Comparison of US Federal and Foundation Funding of Research for Sickle Cell Disease and Cystic Fibrosis and Factors Associated With Research Productivity

IMPORTANCE

Sickle cell disease (SCD) and cystic fibrosis (CF) are severe autosomal recessive disorders associated with intermittent disease exacerbations that require hospitalizations, progressive chronic organ injury, and substantial premature mortality. Research funding is a limited resource and may contribute to health care disparities, especially for rare diseases that disproportionally affect economically disadvantaged groups.

OBJECTIVE

To compare disease-specific funding between SCD and CF and the association between funding and research productivity.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study examined federal and foundation funding, publications indexed in PubMed, clinical trials registered in ClinicalTrials.gov, and new drug approvals from January 1, 2008, to December 31, 2018, in an estimated US population of approximately 90 000 individuals with SCD and approximately 30 000 individuals with CF.

MAIN OUTCOMES AND MEASURES

Federal and foundation funding, publications indexed in PubMed, clinical trial registrations, and new drug approvals.

RESULTS

From 2008 through 2018, federal funding was greater per person with CF compared with SCD (mean [SD], $2807 [$175] vs $812 [$147]; P < .001). Foundation expenditures were greater for CF than for SCD (mean [SD], $7690 [$3974] vs $102 [$13.7]; P < .001). Significantly more research articles (mean [SD], 1594 [225] vs 926 [157]; P < .001) and US Food and Drug Administration drug approvals (4 vs 1) were found for CF compared with SCD, but the total number of clinical trials was similar (mean [SD], 27.3 [6.9] vs 23.8 [6.3]; P = .22).

CONCLUSIONS AND RELEVANCE

The findings show that disparities in funding between SCD and CF may be associated with decreased research productivity and novel drug development for SCD. Increased federal and foundation funding is needed for SCD and other diseases that disproportionately affect economically disadvantaged groups to address health care disparities.

Appetitive characteristics in children with cystic fibrosis: Questionnaire validation and associations with nutritional status

BACKGROUND

Appetitive characteristics are an important factor in the nutritional status of children with cystic fibrosis (CF). We administered a brief parent-report eating behavior questionnaire, validated in healthy children, to determine the relationship between appetitive characteristics and body weight in children with CF.

METHODS

Parents of children attending the Johns Hopkins Pediatric CF Clinic completed the Child Eating Behavior Questionnaire (CEBQ) at a routine clinic visit. Responses were correlated with anthropometric and other clinical data.

RESULTS

Parents of 64 children with CF aged 7.74 ± 3.17 years (mean ± SD) completed the CEBQ. The CEBQ subscales demonstrated good internal consistency (Cronbach's α = 0.76-0.94). Higher scores on food avoidance subscales (Slowness in Eating) were associated with lower body mass index (BMI) z-scores, and higher scores on food approach subscales (Food Responsiveness, Enjoyment of Food, Emotional Overeating) with higher BMI z-scores. Children with feeding aids (i.e. gastric tube or appetite-stimulating medications) demonstrated greater food avoidance (Slowness in Eating) and lesser food approach (Enjoyment of Food) when compared to those without feeding aids. Children with pancreatic insufficiency also demonstrated greater food avoidance (Slowness in Eating).

CONCLUSIONS

The CEBQ can be used in a clinical setting to identify children with CF with appetitive characteristics associated with difficulty gaining weight. These children could potentially benefit from earlier interventions to aid in weight gain. Characterization of appetite using the CEBQ could aid investigation of the biological etiology of low appetite, and optimization of clinical and parental approaches to achieving a healthy nutritional status.

[Value of sweat conductivity testing in the diagnosis of cystic fibrosis in children]

Objective: To assess the diagnostic value of sweat conductivity testing in Chinese children with cystic fibrosis (CF). Methods: This is a retrospective study. Sweat conductivity tests were conducted in 45 CF children (CF group) and 200 non-CF children (non-CF group) diagnosed with other chronic pulmonary diseases at the No. 2 Department of Respiratory Medicine, Beijing Children's Hospital from May 2014 to June 2018. Pearson's chi-square test was used to assess the differences between CF and non-CF groups. A receiver operating characteristic curve was constructed to calculate the best cut-off value to diagnose or rule out CF. The pulmonary function parameters (forced expiratory volume in the first second, forced vital capacity,forced expiratory flows at 75% of exhaled vital capacity) of CF children over 6 years old were analyzed. The relationship between sweat conductivity and pulmonary function was compared between the two groups (80-120mmol/L vs.>120mmol/L). Results: The age of CF group was 9 (7,12) years old, 19 males (42%) and 26 females(58%); the age of non-CF group was 8 (5,11) years old, 106 males (53%) and 94 females(47%). The results of sweat conductivity test showed that sweat conductivity in CF group 108(99, 122) mmol/L was significantly higher than that in non-CF group 43(36, 52) mmol/L (χ(2)=207, P<0.01). A cut-off value of 80 mmol/L for CF diagnosis showed a sensitivity of 93.3% and a specificity of 98.5%. The receiver operating characteristic curve analysis suggested the best conductivity cut-off value for the diagnosis of CF was at 83.5 mmol/L,with a sensitivity of 93.3% and a specificity of 100%,and an area under the curve of 0.993 (95% confidence interval 0.985-1.000). The best conductivity cut-off value to rule out CF diagnosis was at 63.5 mmol/L,with a sensitivity of 97.8% and a specificity of 90.5%. There was no correlation between the level of sweat conductivity and the extent of pulmonary function decline. Conclusions: Sweat conductivity testing can be used for the screening of CF in Chinese children. A diagnosis of CF should be considered if the value is greater than 80 mmol/L.

Effect of ivacaftor on mucociliary clearance and clinical outcomes in cystic fibrosis patients with G551D-CFTR

BACKGROUND

The ability to restore cystic fibrosis transmembrane regulator (CFTR) function with effective small molecule modulators in patients with cystic fibrosis provides an opportunity to study relationships between CFTR ion channel function, organ level physiology, and clinical outcomes.

METHODS

We performed a multisite, prospective, observational study of ivacaftor, prescribed in patients with the G551D-CFTR mutation. Measurements of lung mucociliary clearance (MCC) were performed before and after treatment initiation (1 and 3 months), in parallel with clinical outcome measures.

RESULTS

Marked acceleration in whole lung, central lung, and peripheral lung MCC was observed 1 month after beginning ivacaftor and was sustained at 3 months. Improvements in MCC correlated with improvements in forced expiratory volume in the first second (FEV1) but not sweat chloride or symptom scores.

CONCLUSIONS

Restoration of CFTR activity with ivacaftor led to significant improvements in MCC. This physiologic assessment provides a means to characterize future CFTR modulator therapies and may help to predict improvements in lung function.

TRIAL REGISTRATION

ClinicialTrials.gov, NCT01521338.

FUNDING

CFF Therapeutics (GOAL11K1).

Cystic fibrosis in the era of precision medicine

The treatment of people with cystic fibrosis (CF) has been transformed by the availability of drugs that target the basic chloride defect in the disease. The use of drugs that target specific molecular defects embodies the goals of precision medicine, which incorporate preventive and therapeutic strategies and takes into account differences among individuals. However, the entirety of CF care, from diagnosis to understanding the clinical phenotype and developing a therapeutic strategy, depends on taking into account individual characteristics to achieve optimal outcomes. Future therapies are likely to be even more individualized ushering in a new era of precision medicine.

Asthma Screening in Pediatric Sickle Cell Disease: A Clinic-Based Program Using Questionnaires and Spirometry

A clinician diagnosis of asthma is associated with increased morbidity and mortality in people with sickle cell disease (SCD). We hypothesized that a screening program would help identify children with asthma needing referral to pulmonary clinic. We conducted a single-center project to screen patients with SCD for asthma using a previously validated questionnaire (Breathmobile) and for pulmonary function abnormalities with portable spirometry. Participants with a positive questionnaire and/or abnormal spirometry were referred to pediatric pulmonary clinic. We evaluated clinical associations with abnormal spirometry and questionnaire responses. Of the 157 participants, 58 (37%) had a positive asthma screening questionnaire. Interpretable spirometry was available for 105 (83% of those eligible) and of these, 35 (34%) had abnormal results. The asthma questionnaire was 87.5% sensitive [95% confidence interval (CI) 74.8-95.3] and 85.3% specific (95% CI 77.3-91.4) to detect a clinician diagnosis of asthma. Participants with positive questionnaires were older (mean age 12.2 vs. 9.9 years, P = 0.012). Spirometry identified 16 additional participants who had normal asthma questionnaires. Seventy-four participants (47%) were referred to pediatric pulmonary clinic and 25 (34%) of these participants scheduled clinic appointments; however, only 13 (52%) were evaluated in pulmonary clinic. Clinic-based asthma screening and spirometry frequently identified individuals with asthma and pulmonary function abnormalities. Only 22% of those referred were eventually seen in pulmonary clinic. The impact of improved screening and treatment on the pulmonary morbidity in SCD needs to be defined and is an area for future investigation. In addition, case management or multidisciplinary clinics may enhance future screening programs.

Home Monitoring of Patients with Cystic Fibrosis to Identify and Treat Acute Pulmonary Exacerbations. eICE Study Results

RATIONALE

Individuals with cystic fibrosis (CF) experience frequent acute pulmonary exacerbations, which lead to decreased lung function and reduced quality of life.

OBJECTIVES

The goal of this study was to determine if an intervention directed toward early detection of pulmonary exacerbations using home spirometry and symptom monitoring would result in slower decline in lung function than in control subjects.

METHODS

We conducted a multicenter, randomized trial at 14 CF centers with subjects at least 14 years old. The early intervention arm subjects measured home spirometry and symptoms electronically twice per week. Sites were notified if a participant met criteria for an exacerbation and contacted participants to determine if treatment for acute exacerbation was required. Participants in the usual care arm were seen every 3 months and were asked to contact the site if they were concerned about worsening pulmonary symptoms.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was the 52-week change in FEV₁. Secondary outcomes included time to first exacerbation and subsequent exacerbation, quality of life, and change in weight. A total of 267 patients were randomized, and the study arms were well matched at baseline. There was no significant difference between study arms in 52-week mean change in FEV₁ slope (mean slope difference, 0.00 L, 95% confidence interval, -0.07 to 0.07; P = 0.99). The early intervention arm subjects detected exacerbations more frequently than usual care arm subjects (time to first exacerbation hazard ratio, 1.45; 95% confidence interval, 1.09 to 1.93; P = 0.01). Adverse events were not significantly different between treatment arms.

CONCLUSIONS

An intervention of home monitoring among patients with CF was able to detect more exacerbations than usual care, but this did not result in slower decline in lung function. Clinical trial registered with www.clinicaltrials.gov (NCT01104402).

Homogeneity of Aerosol Deposition and Mucociliary Clearance are Improved Following Ivacaftor Treatment in Cystic Fibrosis

BACKGROUND

Using planar gamma scintigraphy of inhaled radioaerosols, we have developed new analytical methods for assessing homogeneity of aerosol deposition and time-dependent particle clearance on a pixel-by-pixel basis, and applied them to a therapeutic cystic fibrosis (CF) study.

METHODS

At baseline and 1 month after beginning treatment with ivacaftor, a cystic fibrosis transmembrane regulator modulator for CF patients with at least one copy of the G551D mutation (n = 13), initial deposition and subsequent mucociliary clearance (MCC) of radiolabeled particles (^99mTechnetium-sulfur colloid, 5 μm mass median aerodynamic diameter) inhaled under controlled breathing conditions were measured.

RESULTS

Improved homogeneity of deposition, that is, decreased areas of higher and lower particle deposition in the lungs, was observed following ivacaftor treatment. The mean number ratio (NR) of pixels with higher deposition, relative to lung size, decreased from 0.14 to 0.09 (p = 0.003) and mean NR of colder pixels decreased from 0.23 to 0.19 (p = 0.004). Particle clearance was also improved following treatment, with mean MCC through 60 minutes equal to 12% versus 24%, without and with treatment, respectively (p = 0.010). Pixel-level analysis of MCC showed that (1) the fraction of pixels clearing >30% at 60 minutes was increased from 0.13 to 0.32 (p = 0.007); and (2) the fraction of pixels clearing <5% at 60 minutes was decreased from 0.54 to 0.37 (p = 0.014), indicating an overall recruitment of more fast-clearing lung regions with ivacaftor treatment.

CONCLUSION

These detailed pixel analyses of deposition and clearance homogeneity may supplement traditional methods that use large regions of interest for assessing efficacy and mechanisms of therapeutic intervention in patients with airways disease.

Extracorporeal Photopheresis in the Treatment of Persistent Rejection in a Pediatric Lung Transplant Recipient

Lung transplantation is an accepted therapy for children with end-stage lung disease. One-year lung transplant survival rates of 86% have been reported by the United Network for Organ Sharing. Allograft rejection is a common cause of death following transplantation. Extracorporeal photopheresis is a novel therapy used to treat solid-organ rejection; this therapy involves separating the leukocyte-rich fraction from whole blood, treating with psoralen and ultraviolet light A exposure. The objective of therapy is to reverse progressive and persistent rejection. Working collaboratively with an institution that offers extracorporeal photopheresis may provide an alternative or additional therapy in the management of ongoing rejection following solid-organ transplantation.

Clinical Phenotypes and Genotypic Spectrum of Cystic Fibrosis in Chinese Children

OBJECTIVES

To characterize the clinical phenotypes and genotypic spectrum of cystic fibrosis (CF) in Chinese children.

STUDY DESIGN

We recruited and characterized the phenotypes of 21 Chinese children with CF. All 27 exons and their flanking sequences of the CF transmembrane conductance regulator gene were amplified and sequenced to define the genotypes.

RESULTS

Bronchiectasis (95.2%) and sinusitis (76.2%) were the most common clinical presentations among our patients. By contrast, pancreatic insufficiency was rare (14.3%). The predominant organism found in the airways was Pseudomonas aeruginosa (66.7%). There were obvious reductions of forced expiratory volume in the first second (mean ± SD: 71.8% ± 17.2% predicted) and forced expiratory flows at 75% of exhaled vital capacity (33.7% ± 20.4% predicted) in children with CF. Overall, we identified 22 different mutations, including 12 missense, 5 nonsense, 2 frameshift, 1 in-frame insertion, 1 splice site, and 1 3'untranslated region mutation. Of these, 7 were novel observations (W216X[780G→A], 1092insA, Q359X, D567Y, 2623-126T→C, 3439delA and 4575+110C→G), and the most common types were L88X and I556V. One de novo mutation (1092insA) was also revealed. Except for N1303K and R334W, none of them were present in the common Caucasian CF transmembrane conductance regulator mutation-screening panels.

CONCLUSIONS

There was a 5.7-year delay between the first clinical presentation and the eventual CF diagnosis, suggesting that CF may be underdiagnosed in China. The clinical phenotypes and genotypic spectrum are different from that observed in Caucasians.

Web-Based Intervention for Nutritional Management in Cystic Fibrosis: Development, Usability, and Pilot Trial

OBJECTIVES

Usability and pilot testing of a web intervention (BeInCharge.org [BIC]) of behavior plus nutrition intervention for children with cystic fibrosis (CF) ages 4-9 years.

METHODS

Think Aloud methodology was used with five mothers to assess usability and refine the intervention. A pilot trial was then conducted with 10 mothers of children with CF ages 4-9 years randomized to the web-based BIC or a Standard Care Control (STC). Change in weight gain for each group was compared in a pre-to-post design.

RESULTS

Mothers rated the usability and clarity of BIC highly. The pilot trial showed children of mothers who received BIC had a significant change in weight pre-to-post-treatment (0.67 kg, p = .04). Change for the STC was not significant (0.41 kg, p = .10).

CONCLUSIONS

A web-based behavior plus nutrition intervention appears promising in increasing weight gain in children with CF.

Mucus removal is impaired in children with cystic fibrosis who have been infected by Pseudomonas aeruginosa

OBJECTIVE

To determine if mucus removal is impaired in children with cystic fibrosis (CF) who have been recently infected with Pseudomonas aeruginosa.

STUDY DESIGN

We compared mucociliary clearance (MCC), cough clearance (CC), lung morphology, and forced expiratory volume in 1 second (FEV1) in 7- to 14-year-old children with CF and mild lung disease (FEV1 ≥ 80%). Children were either P. aeruginosa negative (n = 8), or P. aeruginosa positive (P. aeruginosa obtained from at least 1 airway culture in the preceding 18 months) (n = 10). MCC and CC were quantified from gamma camera imaging of the right lung immediately after inhalation of (99m)technetium sulfur-colloid (time 0), over the next 60 minutes (average percent clearance over the first 60 minutes [AveMCC60]), 60-90 minutes (average percent clearance between 70 and 90 minutes [AveMCC/CC90]), and after 24 hours (percent clearance after 24 hours [MCC24hrs]). Children coughed 30 times between 60 and 90 minutes. Lung morphology was assessed by high resolution computed tomography (HRCT) scores of both lungs (total score) and of the right lung, using the Brody scale. Percent AveMCC60, AveMCC/CC90, MCC24hrs, FEV1, and HRCT scores were compared across the 2 groups using unpaired t tests. Associations were assessed using Spearman correlation.

RESULTS

There were no differences between the 2 groups in AveMCC60, MCC24hrs, mean HRCT total scores, right lung HRCT scores, or mean FEV1. AveMCC/CC90 was significantly decreased in children with P. aeruginosa compared with those without (16.2% ± 11.0% vs 28.6% ± 7.8%, respectively; P = .016). There was a significant negative correlation of AveMCC60 and AveMCC/CC90 with total lung HRCT score (all P < .05) but not with FEV1.

CONCLUSIONS

Infection with P. aeruginosa is associated with a significant slowing of MCC/CC in children with mild CF and may be a more sensitive indicator of the effects of P. aeruginosa than measurements of FEV1.

Environmental allergies and respiratory morbidities in cystic fibrosis

BACKGROUND

Cystic fibrosis (CF) is characterized by recurrent respiratory infections and progressive lung disease. Although environmental factors account for 50% of the variation in CF lung function, few specific exposures have been identified. Studies using small study samples focusing on environmental allergies in CF have had inconsistent results. Our objective was to examine the role of environmental allergies in upper and lower respiratory tract morbidities in CF.

METHODS

A total of 1,321 subjects with CF were recruited through the U.S. CF Twin-Sibling Study. Questionnaires were used to determine the presence/absence of environmental allergies. Questionnaires, chart review, and U.S. CF Foundation Patient Registry data were used to track outcomes.

RESULTS

Within the study sample 14% reported environmental allergies. Environmental allergies were associated with a higher risk of sinus disease (adjusted OR: 2.68; P < 0.001) and nasal polyps (adjusted OR: 1.74; P = 0.003). Environmental allergies were also associated with a more rapid decline in lung function (additional -1.1%/year; P = 0.001). However, allergies were associated with a later median age of acquisition of Pseudomonas aeruginosa (6.6 years vs. 4.4 years; log rank P = 0.027). The reported use of common allergy medications, anti-histamines and leukotriene inhibitors, did not alter the frequency of respiratory morbidities.

CONCLUSIONS

Environmental allergies are associated with an increased risk of sinus disease and nasal polyps and a more rapid decline in CF lung function, but may have a protective effect against the acquisition of P. aeruginosa. Prospective studies are needed to confirm these associations which have implications for more aggressive management of allergies.

Association of lung function, chest radiographs and clinical features in infants with cystic fibrosis

The optimal strategy for monitoring cystic fibrosis lung disease in infancy remains unclear. Our objective was to describe longitudinal associations between infant pulmonary function tests, chest radiograph scores and other characteristics. Cystic fibrosis patients aged ≤24 months were enrolled in a 10-centre study evaluating infant pulmonary function tests four times over a year. Chest radiographs ∼1 year apart were scored using the Wisconsin and Brasfield systems. Associations of infant pulmonary function tests with clinical characteristics were evaluated with mixed effects models. The 100 participants contributed 246 acceptable flow/volume (forced expiratory volume in 0.5 s (FEV0.5) and forced expiratory flow at 75% of the forced vital capacity (FEF75%)), 303 functional residual capacity measurements and 171 chest radiographs. Both Brasfield and Wisconsin chest radiograph scores worsened significantly over the 1-year interval. Worse Wisconsin chest radiograph scores and Staphylococcus aureus were both associated with hyperinflation (significantly increased functional residual capacity), but not with diminished FEV0.5 or FEF75%. Parent-reported cough was associated with significantly diminished forced expiratory flow at 75% but not with hyperinflation. In this infant cohort in whom we previously reported worsening in average lung function, chest radiograph scores also worsened over a year. The significant associations detected between both Wisconsin chest radiograph score and S. aureus and hyperinflation, as well as between cough and diminished flows, reinforce the ability of infant pulmonary function tests and chest radiographs to detect early cystic fibrosis lung disease.

Multisite comparison of mucociliary and cough clearance measures using standardized methods

BACKGROUND

A standardized protocol for measuring mucociliary (MCC) and cough clearance (CC) was developed and tested at the University of North Carolina at Chapel Hill, NC (UNC), Johns Hopkins University (JHU), and the University of Pittsburgh (Pitt).

METHODS

A total of 50 healthy nonsmoking adults with normal lung function were studied at the three sites: 30 [21 males/9 females (21M/9F)] at UNC, 10 (6M/4F) at JHU, and 10 (4M/6F) at Pitt. Subjects inhaled an aerosol of (99m)technetium sulfur colloid in 0.9% saline (mass median aerodynamic diameter=5.4 μm) under controlled breathing conditions (500 mL/sec, 30 breaths/min) by following a metronome and flow signal from a commercial dosimeter. Following inhalation, subjects sat in front of a gamma camera as sequential lung images were acquired for 60 min. Subjects then coughed 60 times, and images were acquired after each set of 20 coughs, i.e., at 70, 80, and 90 min. Subjects returned to the laboratory approximately 24 hr later for a final image of residual lung activity. Initial aerosol distribution was measured as a central/peripheral (C/P) ratio of activity. MCC/CC was expressed as the area under the retention versus time curve over 90 min (AUC90).

RESULTS

A multivariate analysis of clearance versus time with site and C/P as covariates showed no significant site-specific differences. Interestingly, MCC/CC was greater in females (n=19) versus males (n=31), with AUC90=0.84 ± 0.11 and 0.90±0.07, respectively (p=0.03), for the combined data set from all sites (not significant for any given site). There were no gender differences for either C/P ratio or 24-hr clearance.

CONCLUSIONS

This standardized protocol may prove beneficial in multicenter trials for testing new therapies that are designed to improve MCC/CC.

A pilot study to examine the effect of chronic treatment with immunosuppressive drugs on mucociliary clearance in a vagotomized murine model

BACKGROUND

Previously, we have demonstrated that mucociliary clearance (MCC) is diminished within the first months after surgery in lung transplant patients and the explanation for the reduction in MCC is unknown. We hypothesized that chronic treatment with a commonly prescribed regimen of immunosuppressive drugs significantly impairs MCC. We tested this hypothesis in a murine model of lung transplantation.

METHODS

Fifteen C57BL/6 mice underwent vagotomy on the right side to simulate denervation associated with lung transplantation in humans. For 6 days, seven mice (controls) were intraperitoneally injected with three 100 µL doses of phosphate buffered saline and eight mice (immunosuppressed) were injected with three 100 µL injections of tacrolimus (1 mg/kg), mycophenolate mofetil (30 mg/kg), and prednisone (2 mg/kg) once daily. Then, mice inhaled the radioisotope (99m)technetium and underwent gamma camera imaging of their lungs for 6.5 hrs. Counts in the right lung at 1-1.5 hrs and at 6-6.5 hrs were first background-corrected and then decay-corrected to time 0 counts. Decay-corrected counts were then divided by time 0 counts. Retention at each time point was subtracted from 1.00 and multiplied by 100% to obtain percent removed by mucociliary clearance.

RESULTS

Although there was a slowing of MCC at 1-1.5 hrs for the immunosuppressed mice, there was no statistical difference in MCC measured at 1-1.5 hrs for the two groups of mice. At 6-6.5 hrs, MCC was significantly slower in the immunosuppressed mice, compared to controls, with 7.78±5.9% cleared versus 23.01±11.7% cleared, respectively (p = 0.006).

CONCLUSIONS

These preliminary results suggest that chronic treatment with immunosuppressive medications significantly slows MCC in vagotomized C57BL/6 mice. These findings could shed light on why MCC is reduced in lung transplant patients whose lungs are denervated during surgery and who are chronically treated with immunosuppressive drugs post surgery.

Nutritional outcomes following gastrostomy in children with cystic fibrosis

OBJECTIVE

In 2005 the Cystic Fibrosis (CF) Foundation recommended that children with CF maintain a body mass index (BMI) ≥ 50th percentile. Our study evaluated if gastrostomy (GT) placement increases the likelihood of reaching that goal compared to a standardized nutrition protocol.

STUDY DESIGN

Retrospective study of 20 children with CF ages 2-20 years with GTs placed from 2005 to 2010. Each case was pair-matched on age, sex, pancreatic status, BMI, and lung function with a nonGT child with CF. Outcome measures included nutritional status and lung function at 6 months and 1 year.

RESULTS

At baseline, mean ± SD BMI Z-scores were similar (cases -1.19 ± 0.60, controls -1.10 ± 0.50; P = 0.10). Cases had a significant 6-month increase in mean BMI Z-score to -0.29 ± 0.84 compared to -1.02 ± 0.67 for controls (P < 0.001). By 1 year, the change in mean BMI Z-score was less different (cases -0.41 ± 0.76, controls -0.71 ± 0.51; P = 0.07). Both groups had stable lung function. From exact logistic regression analysis, the odds ratio for cases compared to controls of reaching BMI ≥ 50th percentile was 9.70 (95% CI: 1.05-484.7; P = 0.04) at 6 months and 3.65 (95%CI: 0.69-25.86; P = 0.16) at 1 year.

CONCLUSION

Our study suggests that children with CF who receive GTs are more likely to achieve BMI ≥ 50th percentile than matched children without GTs.

Treatment of plastic bronchitis by orthotopic heart transplantation

This case illustrates the successful use of orthotopic heart transplantation for the treatment of plastic bronchitis in a 6-year-old boy with hypoplastic left heart syndrome, which developed 2 years after Fontan procedure. Transplantation was undertaken after he failed medical management of airway obstruction. He is currently 1-year post-cardiac transplantation and has no evidence of plastic bronchitis despite weaning of an aggressive airway clearance regimen.

Acute inhalation of hypertonic saline does not improve mucociliary clearance in all children with cystic fibrosis

Background

Little is known of how mucociliary clearance (MCC) in children with cystic fibrosis (CF) and normal pulmonary function compares with healthy adults, or how an acute inhalation of 7% hypertonic saline (HS) aerosol affects MCC in these same children.

Methods

We compared MCC in 12 children with CF and normal pulmonary function after an acute inhalation of 0.12% saline (placebo), or HS, admixed with the radioisotope ^{99 m}technetium sulfur colloid in a double-blind, randomized, cross-over study. Mucociliary clearance on the placebo day in the children was also compared to MCC in 10 healthy, non-CF adults. Mucociliary clearance was quantified over a 90 min period, using gamma scintigraphy, and is reported as MCC at 60 min (MCC60) and 90 min (MCC90).

Results

Median [interquartile range] MCC60 and MCC90 in the children on the placebo visit were 15.4 [12.4-24.5]% and 19.3 [17.3-27.8%]%, respectively, which were similar to the adults with 17.8 [6.4-28.7]% and 29.6 [16.1-43.5]%, respectively. There was no significant improvement in MCC60 (2.2 [-6.2-11.8]%) or MCC90 (2.3 [-1.2-10.5]%) with HS, compared to placebo. In addition, 5/12 and 4/12 of the children showed a decrease in MCC60 and MCC90, respectively, after inhalation of HS. A post hoc subgroup analysis of the change in MCC90 after HS showed a significantly greater improvement in MCC in children with lower placebo MCC90 compared to those with higher placebo MCC90 (p = 0.045).

Conclusions

These data suggest that percent MCC varies significantly between children with CF lung disease and normal pulmonary functions, with some children demonstrating MCC values within the normal range and others showing MCC values that are below normal values. In addition, although MCC did not improve in all children after inhalation of HS, improvement did occur in children with relatively low MCC values after placebo. This finding suggests that acute inhalation of hypertonic saline may benefit a subset of children with low MCC values.

Trial Registration

ClinicalTrials.gov: NCT01293084

Implementation of the first worldwide quality assurance program for cystic fibrosis multiple mutation detection in population-based screening

BACKGROUND

CDC's Newborn Screening Quality Assurance Program collaborated with several U.S. Cystic Fibrosis Care Centers to collect specimens for development of a molecular CFTR proficiency testing program using dried-blood spots for newborn screening laboratories.

METHODS

Adult and adolescent patients or carriers donated whole blood that was aliquoted onto filter paper cards. Five blind-coded specimens were sent to participating newborn screening laboratories quarterly. Proficiency testing results were evaluated based on presumptive clinical assessment. Individual evaluations and summary reports were sent to each participating laboratory and technical consultations were offered if incorrect assessments were reported.

RESULTS

The current CDC repository contains specimens with 39 different CFTR mutations. Up to 45 laboratories have participated in the program. Three years of data showed that correct assessments were reported 97.7% of the time overall when both mutations could be determined. Incorrect assessments that could have lead to a missed case occurred 0.9% of the time, and no information was reported 1.1% of the time due to sample failure.

CONCLUSIONS

Results show that laboratories using molecular assays to detect CFTR mutations are performing satisfactorily. The programmatic results presented demonstrate the importance and complexity of providing proficiency testing for DNA-based assays.

Pain is a common problem affecting clinical outcomes in adults with cystic fibrosis

BACKGROUND

As the cystic fibrosis (CF) population has aged, many chronic health problems have emerged, including diabetes mellitus and osteoporosis. Previous studies have suggested that pain is common in patients with CF; however, little is known about the factors associated with it or its impact on clinical outcomes. We hypothesized that pain is common, is associated with psychologic distress, and adversely affects clinical outcomes.

METHODS

From February 1, 2008, to April 3, 2008, adults with CF from Johns Hopkins Hospital were surveyed about their pain. Outcomes were assessed for 12 months following survey completion. Bivariate analyses were performed using Wilcoxon log rank, Kruskal-Wallis tests, and Spearman correlations. Logistic regression models and Cox proportional hazard models were used to analyze clinical outcomes.

RESULTS

Eighty-three patients (61%) completed the survey. Eighty-two percent of patients reported pain within the past month, the most common sites being the head, sinuses, back, and chest. Pain frequently interfered with general activities (41.9%), mood (56.8%), and work (47.3%). Symptoms of depression and anxiety, as well as lower quality-of-life (QOL) scores, were associated with the presence of pain (P < .05 for each). The risk of pulmonary exacerbations was increased in patients with higher levels of pain, even after adjusting for FEV(1) and age (OR = 1.65; P = .038; 95% CI, 1.03-2.64). Additionally, the risk of death was higher in patients with higher average pain scores (HR = 2.28; P = .008; 95% CI = 1.2-4.2).

CONCLUSIONS

Pain is common in adults with CF, interferes with activities, and is associated with lower QOL and an increased risk of both exacerbations and death.

Longitudinal association between medication adherence and lung health in people with cystic fibrosis

BACKGROUND

This study examined the relationship of medication adherence to frequency of pulmonary exacerbation and rate of decline in FEV(1)% predicted (FEV(1)).

METHODS

95 CF patients aged 6 years or older and prescribed a pulmonary medication, were enrolled in a longitudinal retrospective review of medication adherence and health outcomes (the occurrence and frequency of intravenous (IV) antibiotic treatments and FEV(1)) over 12-months. Pharmacy refill records were used to calculate a medication possession ratio (MPR).

RESULTS

Composite MPR predicted the occurrence of at least one pulmonary exacerbation requiring a course of IV antibiotics (IRR=2.34, p=0.05), but not the frequency of exacerbations, after controlling for gender, baseline FEV(1,) and regimen complexity. Composite MPR predicted baseline FEV(1) (estimate=29.81, p=.007), but not decline in FEV(1).

CONCLUSIONS

These results demonstrate a significant relation between medication adherence and IV antibiotics in CF patients, highlighting the importance of addressing adherence during clinic visits to improve health outcomes.

CFTR transcription defects in pancreatic sufficient cystic fibrosis patients with only one mutation in the coding region of CFTR

BACKGROUND

Patients with cystic fibrosis (CF) manifest a multisystem disease due to deleterious mutations in each gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). However, the role of dysfunctional CFTR is uncertain in individuals with mild forms of CF (ie, pancreatic sufficiency) and mutation in only one CFTR gene.

METHODS

Eleven pancreatic sufficient (PS) CF patients with only one CFTR mutation identified after mutation screening (three patients), mutation scanning (four patients) or DNA sequencing (four patients) were studied. Bi-directional sequencing of the coding region of CFTR was performed in patients who had mutation screening or scanning. If a second CFTR mutation was not identified, CFTR mRNA transcripts from nasal epithelial cells were analysed to determine if any PS-CF patients harboured a second CFTR mutation that altered RNA expression.

RESULTS

Sequencing of the coding regions of CFTR identified a second deleterious mutation in five of the seven patients who previously had mutation screening or mutation scanning. Five of the remaining six patients with only one deleterious mutation identified in the coding region of one CFTR gene had a pathologic reduction in the amount of RNA transcribed from their other CFTR gene (8.4-16% of wild type).

CONCLUSIONS

These results show that sequencing of the coding region of CFTR followed by analysis of CFTR transcription could be a useful diagnostic approach to confirm that patients with mild forms of CF harbour deleterious alterations in both CFTR genes.

Early eradication of Pseudomonas aeruginosa in patients with cystic fibrosis

Pseudomonas aeruginosa (Pa) is the predominant organism infecting the airways of patients with cystic fibrosis (CF). This organism has an armamentarium of survival mechanisms that allows it to survive in the CF airway. Since colonization and chronic infection with Pa is associated with poorer lung function and increased morbidity and mortality, therapies that can prevent infection could significantly improve the lives of patients with CF. Numerous studies have examined the effects of treatment on the eradication of Pa as a means to ameliorate disease. This article outlines the pathophysiology and clinical implication of Pa acquisition, and reviews the existing treatment regimens aimed at early eradication of Pa in patients with CF.

Familial neuroendocrine cell hyperplasia of infancy

BACKGROUND

Neuroendocrine cell hyperplasia of infancy (NEHI) is a recently described children's interstitial lung disease (chILD) disorder of unknown etiology. It manifests clinically with tachypnea, retractions, hypoxemia, and crackles. The characteristic radiographic appearance consists of pulmonary hyperexpansion and ground-glass densities on high-resolution computed tomography (HRCT). Lung histology shows hyperplasia of bombesin-immunopositive neuroendocrine cells within distal bronchioles and alveolar ducts without other identifiable lung pathology or developmental anomaly.

METHODS

We describe four families with multiple siblings diagnosed with NEHI. Cases were identified at three pediatric centers. Inclusion criteria included clinical findings consistent with NEHI, lung biopsy confirmation in the index case, and a diagnostic HRCT or biopsy in other siblings.

RESULTS

Each family had a proband diagnosed with NEHI based upon pathologic review, and at least one additional sibling diagnosed either by pathologic review or HRCT. All patients presented between 2 and 15 months of age. Both male and female children were affected. The majority of the patients underwent both HRCT and lung biopsy. There were no deaths among affected children. No environmental exposures or other potential etiologies were identified as a cause of presenting symptoms.

CONCLUSIONS

The familial occurrence of NEHI suggests the possibility of a genetic etiology for this disorder and highlights the importance of taking a complete family medical history for infants presenting with a suggestive clinical picture. Identification of familial NEHI patients allows for the opportunity to further our understanding of this disorder, its natural history, the phenotypic spectrum, and potential genetic causes.

Multicenter evaluation of infant lung function tests as cystic fibrosis clinical trial endpoints

RATIONALE

The conducting of clinical trials in infants with cystic fibrosis (CF) has been hindered by lack of sensitive outcome measures.

OBJECTIVES

To evaluate safety, feasibility, and ability to detect abnormalities in lung function of serial pulmonary function tests (PFTs) in infants with CF.

METHODS

Multicenter observational study using a commercial device, rigorous training, ongoing quality control, and over-reading of data by an independent panel. Raised volume rapid thoracoabdominal compression technique and plethysmography were performed at enrollment and at 6 and 12 months, with an additional 1-month reproducibility visit.

MEASUREMENTS AND MAIN RESULTS

A total of 342 procedures were performed in 100 infants with CF at 10 centers. FRC measurements were acceptable at a higher proportion of study visits (89%) than raised volume (72%) or fractional lung volume (68%) measurements. Average Z scores for many parameters differed significantly from historical control values. Mean (95% confidence interval) Z scores were: -0.52 (-0.78 to -0.25) for forced expiratory flow at 75% (FEF₇₅) for FVC; 1.92 (1.39-2.45) for FRC; 1.22 (0.68-1.76) for residual volume; 0.87 (0.60-1.13) for FRC/total lung capacity; and 0.66 (0.27-1.06) for residual volume/total lung capacity. For future multicenter clinical trials using infant PFTs as primary endpoints, minimum detectable treatment effects are presented for several sample sizes.

CONCLUSIONS

In this 10-center study, key PFT measures were significantly different in infants with CF than in historical control subjects. However, infant PFTs do not yet appear ready as primary efficacy endpoints for multicenter clinical trials, particularly at inexperienced sites, based on acceptability rates, variability, and potentially large sample sizes required to detect reasonable treatment effects.

Location and duration of treatment of cystic fibrosis respiratory exacerbations do not affect outcomes

RATIONALE

Individuals with cystic fibrosis (CF) are subject to recurrent respiratory infections (exacerbations) that often require intravenous antibiotic treatment and may result in permanent loss of lung function. The optimal means of delivering therapy remains unclear.

OBJECTIVES

To determine whether duration or venue of intravenous antibiotic administration affect lung function.

METHODS

Data were retrospectively collected on 1,535 subjects recruited by the US CF Twin and Sibling Study from US CF care centers between 2000 and 2007.

MEASUREMENTS AND MAIN RESULTS

Long-term decline in FEV₁ after exacerbation was observed regardless of whether antibiotics were administered in the hospital (mean, -3.3 percentage points [95% confidence interval, -3.9 to -2.6]; n = 602 courses of therapy) or at home (mean, -3.5 percentage points [95% confidence interval, -4.5 to -2.5]; n = 232 courses of therapy); this decline was not different by venue using t tests (P = 0.69) or regression (P = 0.91). No difference in intervals between courses of antibiotics was observed between hospital (median, 119 d [interquartile range, 166]; n = 602) and home (median, 98 d [interquartile range, 155]; n = 232) (P = 0.29). Patients with greater drops in FEV₁ with exacerbations had worse long-term decline even if lung function initially recovered with treatment (P < 0.001). Examination of FEV₁ measures obtained during treatment for exacerbations indicated that improvement in FEV₁ plateaus after 7-10 days of therapy.

CONCLUSIONS

Intravenous antibiotic therapy for CF respiratory exacerbations administered in the hospital and in the home was found to be equivalent in terms of long-term FEV₁ change and interval between courses of antibiotics. Optimal duration of therapy (7-10 d) may be shorter than current practice. Large prospective studies are needed to answer these essential questions for CF respiratory management.

Lung function and late pulmonary complications among survivors of hematopoietic stem cell transplantation during childhood

Hematopoietic stem cell transplantation (HSCT) is used to treat an expanding array of malignant and non-malignant disorders. Pulmonary complications represent a significant source of morbidity and mortality in HSCT recipients. Young children, whose lungs are still developing and growing, may be especially susceptible to the insults of irradiation, drug toxicities, and recurrent infections associated with immunosuppression. Late pulmonary complications, those occurring more than three months after transplantation, are often noninfectious and present with nonspecific symptomatology. Pulmonary function testing (PFT) is a mainstay of monitoring pulmonary health in HSCT recipients. The pulmonologist should be familiar with common patterns seen on PFT in recipients of HSCT during childhood. In this review, we describe the findings in studies which have examined lung function over time in patients who underwent HSCT during childhood. We discuss patterns of PFT abnormalities, associated noninfectious syndromes and their clinical implications, as well as directions for future research.

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.