Margaret F. Guill

Serial Analysis of the Gut and Respiratory Microbiome in Cystic Fibrosis in Infancy: Interaction between Intestinal and Respiratory Tracts and Impact of Nutritional Exposures

ABSTRACT Pulmonary damage caused by chronic colonization of the cystic fibrosis (CF) lung by microbial communities is the proximal cause of respiratory failure. While there has been an effort to document the microbiome of the CF lung in pediatric and adult patients, little is known regarding the developing microflora in infants. We examined the respiratory and intestinal microbiota development in infants with CF from birth to 21 months. Distinct genera dominated in the gut compared to those in the respiratory tract, yet some bacteria overlapped, demonstrating a core microbiota dominated by Veillonella and Streptococcus. Bacterial diversity increased significantly over time, with evidence of more rapidly acquired diversity in the respiratory tract. There was a high degree of concordance between the bacteria that were increasing or decreasing over time in both compartments; in particular, a significant proportion (14/16 genera) increasing in the gut were also increasing in the respiratory tract. For 7 genera, gut colonization presages their appearance in the respiratory tract. Clustering analysis of respiratory samples indicated profiles of bacteria associated with breast-feeding, and for gut samples, introduction of solid foods even after adjustment for the time at which the sample was collected. Furthermore, changes in diet also result in altered respiratory microflora, suggesting a link between nutrition and development of microbial communities in the respiratory tract. Our findings suggest that nutritional factors and gut colonization patterns are determinants of the microbial development of respiratory tract microbiota in infants with CF and present opportunities for early intervention in CF with altered dietary or probiotic strategies. IMPORTANCE While efforts have been focused on assessing the microbiome of pediatric and adult cystic fibrosis (CF) patients to understand how chronic colonization by these microbes contributes to pulmonary damage, little is known regarding the earliest development of respiratory and gut microflora in infants with CF. Our findings suggest that colonization of the respiratory tract by microbes is presaged by colonization of the gut and demonstrated a role of nutrition in development of the respiratory microflora. Thus, targeted dietary or probiotic strategies may be an effective means to change the course of the colonization of the CF lung and thereby improve patient outcomes. While efforts have been focused on assessing the microbiome of pediatric and adult cystic fibrosis (CF) patients to understand how chronic colonization by these microbes contributes to pulmonary damage, little is known regarding the earliest development of respiratory and gut microflora in infants with CF. Our findings suggest that colonization of the respiratory tract by microbes is presaged by colonization of the gut and demonstrated a role of nutrition in development of the respiratory microflora. Thus, targeted dietary or probiotic strategies may be an effective means to change the course of the colonization of the CF lung and thereby improve patient outcomes.

Cystic Fibrosis Foundation Pulmonary Guideline*. Pharmacologic Approaches to Prevention and Eradication of Initial Pseudomonas aeruginosa Infection

DESCRIPTION The Cystic Fibrosis (CF) Foundation developed clinical care guidelines for the prevention of Pseudomonas aeruginosa infection, the treatment of initial P. aeruginosa infection, and the use of bronchoscopy to obtain routine airway cultures in individuals with CF. METHODS A multidisciplinary committee developed questions about the prevention and treatment of initial P. aeruginosa infection and the use of bronchoscopy to obtain routine airway cultures. The outcome measure of interest was cultures without P. aeruginosa growth. Systematic reviews of PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials were conducted in May 2012 and August 2013. Searches combined controlled vocabulary terms and text words for CF and terms relevant to each question. The entire committee reviewed the evidence, and final recommendation statements were graded using the U.S. Preventive Services Task Force system. Recommendation 1: The CF Foundation strongly recommends inhaled antibiotic therapy for the treatment of initial or new growth of P. aeruginosa from an airway culture (certainty of net benefit, high; estimate of net benefit, substantial; grade of recommendation, A). The favored antibiotic regimen is inhaled tobramycin (300 mg twice daily) for 28 days. Recommendation 2: The CF Foundation recommends against the use of prophylactic antipseudomonal antibiotics to prevent the acquisition P. aeruginosa (certainty of net benefit, moderate; estimate of net benefit, zero; grade of recommendation, D). Recommendation 3: The CF Foundation recommends routine oropharyngeal cultures rather than bronchoalveolar lavage cultures obtained by bronchoscopy in individuals with CF who cannot expectorate sputum to determine if they are infected with P. aeruginosa (certainty of net benefit, moderate; estimate of net benefit, moderate; grade of recommendation, B).

Associations between Gut Microbial Colonization in Early Life and Respiratory Outcomes in Cystic Fibrosis

OBJECTIVE To examine patterns of microbial colonization of the respiratory and intestinal tracts in early life in infants with cystic fibrosis (CF) and their associations with breastfeeding and clinical outcomes. STUDY DESIGN A comprehensive, prospective longitudinal analysis of the upper respiratory and intestinal microbiota in a cohort of infants and young children with CF followed from birth was performed. Genus-level microbial community composition was characterized using 16S-targeted pyrosequencing, and relationships with exposures and outcomes were assessed using linear mixed-effects models, time-to-event analysis, and principal components analysis. RESULTS Sequencing of 120 samples from 13 subjects collected from birth to 34 months revealed relationships between breastfeeding, microbial diversity in the respiratory and intestinal tracts, and the timing of onset of respiratory complications, including exacerbations and colonization with Pseudomonas aeruginosa. Fluctuations in the abundance of specific bacterial taxa preceded clinical outcomes, including a significant decrease in bacteria of the genus Parabacteroides within the intestinal tract prior to the onset of chronic P aeruginosa colonization. Specific assemblages of bacteria in intestinal samples, but not respiratory samples, were associated with CF exacerbation in early life, indicating that the intestinal microbiome may play a role in lung health. CONCLUSIONS Our findings relating breastfeeding to respiratory outcomes, gut diversity to prolonged periods of health, and specific bacterial communities in the gut prior to respiratory complications in CF highlight a connection between the intestinal microbiome and health and point to potential opportunities for antibiotic or probiotic interventions. Further studies in larger cohorts validating these findings are needed.

Clinical Practice Guidelines From the Cystic Fibrosis Foundation for Preschoolers With Cystic Fibrosis

Cystic fibrosis (CF) clinical care guidelines exist for the care of infants up to age 2 years and for individuals ≥6 years of age. An important gap exists for preschool children between the ages of 2 and 5 years. This period marks a time of growth and development that is critical to achieve optimal nutritional status and maintain lung health. Given that disease often progresses in a clinically silent manner, objective and sensitive tools that detect and track early disease are important in this age group. Several challenges exist that may impede the delivery of care for these children, including adherence to therapies. A multidisciplinary committee was convened by the CF Foundation to develop comprehensive evidence-based and consensus recommendations for the care of preschool children, ages 2 to 5 years, with CF. This document includes recommendations in the following areas: routine surveillance for pulmonary disease, therapeutics, and nutritional and gastrointestinal care.

Paraneoplastic Autoimmune Multiorgan Syndrome (Paraneoplastic Pemphigus) in a Child: Case Report and Review of the Literature

Paraneoplastic autoimmune multiorgan syndrome, also known as paraneoplastic pemphigus, has been observed only rarely among children. We describe a 10-year-old boy with typical clinical and histologic findings of paraneoplastic pemphigus associated with Castleman’s disease. His disease was refractory to resection of the tumor and aggressive combination immunosuppressive therapies. The patient died 1 year after presentation, as a result of complications of bronchiolitis obliterans. This case is unusual because of the young age of the patient.

Pediatric acquired immune deficiency syndrome with panhypogammaglobulinemia

Acquired immune deficiency syndrome has been characterized by T cell dysfunction, occasionally normal but more often elevated immunoglobul in levels, and ant ibody to the h u m a n immunodeficiency virus. 1 However, the manifesta t ions of HIV infection can be quite va r i ed ) We report a child with panhypogammaglobul inemia , which caused a delay in recognizing the diagnosis of H I V infection.

Type I diabetes in an adolescent with common variable immunodeficiency

A male adolescent with common variable immunodeficiency developed type I diabetes approximately 1 year after the initiation of immunoglobulin therapy. Immunologic evaluation revealed decreased numbers of T cells and an intrinsic B cell defect in immunoglobulin production. Lymphocytes from the patient failed to generate normal suppressor activity. There were no insulin or islet cell antibodies present in the patients serum or in the commercial immunoglobulin preparations he received. The patients HLA phenotype included HLA-DR3 and 4, placing him genetically at high risk for type I diabetes.

Cystic fibrosis foundation pulmonary guidelines: Use of cystic fibrosis transmembrane conductance regulator modulator therapy in patients with cystic fibrosis

Rationale: Cystic fibrosis (CF) transmembrane conductance regulator (CFTR) modulators are a new class of medications targeting the underlying defect in CF. Ivacaftor (IVA) and IVA combined with lumacaftor (LUM; IVA/LUM) have been approved by the U.S. Food and Drug Administration (FDA) for use in patients with CF. However, the FDA label for these medications encompasses patient groups that were not studied as part of the drug approval process. CF clinicians, patients, and their families have recognized a need for recommendations to guide the use of these medications. Objective: Develop evidence‐based guidelines for CFTR modulator therapy in patients with CF. Methods: A multidisciplinary committee of CF caregivers and patient representatives was assembled. A methodologist, an epidemiologist, a medical librarian, and a biostatistician were recruited to assist with the literature search, evidence grading, and generation of recommendations. The committee developed clinical questions using the Patient‐Intervention‐Comparison‐Outcome format. A systematic review was conducted to find relevant publications. The evidence was then evaluated using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach, and recommendations were made based on this analysis. Results: For adults and children aged 6 years and older with CF due to gating mutations other than G551D or R117H, the guideline panel made a conditional recommendation for treatment with IVA. For those with the R117H mutation, the guideline panel made a conditional recommendation for treatment with IVA for 1) adults aged 18 years or older, and 2) children aged 6‐17 years with a forced expiratory volume in 1 second (FEV1) less than 90% predicted. For those with the R117H mutation, the guideline panel made a conditional recommendation against treatment with IVA for 1) children aged 12‐17 years with an FEV1 greater than 90% predicted, and 2) children less than 6 years of age. Among those with two copies of F508del, the guideline panel made a strong recommendation for treatment with IVA/LUM for adults and children aged 12 years and older with an FEV1 less than 90% predicted; and made a conditional recommendation for treatment with IVA/LUM for 1) adults and children aged 12 years or older with an FEV1 greater than 90% predicted, and 2) children aged 6‐11 years. Conclusions: Using the GRADE approach, we have made recommendations for the use of CFTR modulators in patients with CF. These recommendations will be of help to CF clinicians, patients, and their families in guiding decisions regarding use of these medications.

Atypical presentation of chronic granulomatous disease with Burkholderia cepacia

Chronic granulomatous disease (CGD) is a rare inherited disorder of neutrophil oxidative burst. In patients with CGD, phagocyte destruction of catalase-producing organisms is impaired, resulting in recurrent and potentially fatal infections. Burkholderia cepacia, a catalase-producing organism, is known to infect patients with dysfunctional immune systems. We report a case of a 3-year-old boy with this rare infection that unravelled the diagnosis of CGD.

Use of an In-line Digestive Cartridge With Enteral Nutrition Improves the Weight Trajectory of 2 Children With Cystic Fibrosis Complicated by Another Medical Diagnosis

This clinical observation describes the enteral nutrition (EN) management of 2 toddlers at high nutrition risk due to cystic fibrosis (CF), exocrine pancreatic insufficiency, and comorbid medical conditions. The first case report describes a boy with severe malabsorption after intestinal resection. The second case report reviews a boy with CF and neuroblastoma. When pancreatic enzyme replacement therapy with EN was not effective or appropriate, use of an in-line digestive cartridge was initiated. While using the digestive cartridge, both children showed improvements in their anthropometric measures. This observation reviews the nutrition management throughout their clinical course and describes the use of a digestive cartridge with EN.