Obstructive sleep-disordered breathing in children: assessment and treatment at Arkansas Children's Hospital.

Obstructive sleep-disordered breathing is associated with upper airway obstruction during sleep, which negatively affects sleep quality, ventilation, and/or oxygenation. The condition affects 2-11% of children. In this paper we discuss the epidemiology, pathophysiology, clinical features, diagnosis, and management of obstructive sleep-disordered breathing in children and provide a brief overview of the Arkansas Children's Hospital Sleep Disorder Center.

Complicated Clostridium difficile colitis in children with cystic fibrosis: association with gastric acid suppression?

Patients with cystic fibrosis (CF) have several risk factors for Clostridium difficile colonization such as frequent hospitalization and exposure to a broad array of antibiotics utilized for the control, eradication, and prophylaxis of respiratory pathogens. However, despite this high rate of colonization, the occurrence of C. difficile infection (CDI) in CF is rare. We report three children with CF who presented with severe community-associated CDI. All three children had complicated courses and one died. These children were in good health without significant morbidities, and were not frequently hospitalized nor did they receive frequent antibiotic courses. The occurrence of 3 severe cases within a 15-month period prompted us to report these cases and review the literature in regard to CDI. We reviewed the CF GI tract as possible risk factors for a high rate of C. difficile colonization in individuals with CF. Since a high percentage of individuals with CF are on gastric acid blocking agents, we also focused on gastric acid suppression as a potential risk factor for CDI.

Increased whole body hydroxyproline production as assessed by a new stable isotope technique is associated with hip and spine bone mineral loss in cystic fibrosis.

BACKGROUND & AIMS: Bone mineral loss, reduced lung function and impaired nutritional status are frequently present in children with Cystic Fibrosis (CF). Blood concentrations and urinary excretion of hydroxyproline (OH-PRO) have been used as markers of bone mineral status and lung function in CF. OBJECTIVE: To examine whether whole body hydroxyproline production, as assessed by a new stable isotope methodology, is increased in pediatric patients with CF and associated with bone mineral loss, lung function decline and impaired nutritional status. DESIGN: In a cross-sectional study in 15 pediatric patients with CF and 17 healthy young control subjects, whole body hydroxyproline production (Wb OH-PRO) was assessed in the postabsorptive state by primed-constant and continuous infusion of the stable isotope 2-D-OH-PRO for 3 h. Bone mineral density (BMD) of whole body, hip and spin, and body composition (fat mass and fat-free mass) were determined by dual-energy X-ray Absorptiometry (DXA). Plasma isotopic enrichments and OH-PRO concentrations were measured by LC/MS/MS. RESULTS: Higher values for WbOH-PRO production and plasma OH-PRO concentrations were found in pediatric CF patients than in the healthy young subjects (p < 0.001). WbOH-PRO production was significantly correlated with plasma OH-PRO concentrations in the CF (r: 0.70, p = 0.007) but not in the healthy group. WbOH-PRO production in CF was associated with low BMD values in hip (r = -0.61, p = 0.02) and spine (r = -0.59, p = 0.02) but not with whole body BMD, lung function or body composition. CONCLUSION: A new stable isotope approach revealed enhanced levels of whole body hydroxyproline production rate in pediatric patients with CF, indicative of enhanced whole body collagen breakdown. Increased levels for whole body hydroxyproline production in CF were associated with severe bone mineral loss in hip and spine but not with lung function decline or impaired nutritional status. Registration ClinicalTrials.gov = NCT01172301.

Redesigning care to meet national recommendation of four or more yearly clinic visits in patients with cystic fibrosis.

Cystic fibrosis (CF) is a chronic disease requiring patients to have frequent specialty healthcare visits to delay progression of lung disease, prevent and treat failure to thrive and initiate early interventions to prevent acute illness and complications. The CF Foundation recommends that patients have visits with the CF care team at least every 3 months. During participation in the CF Foundation Learning and Leadership Collaborative IV, the CF team at Arkansas Children's Hospital initiated quality improvement work with the aim to increase the percentage of patients attending clinic four or more times a year from 35% in 2004 and 56% in 2005 (CF Foundation Registry data) to 90% or greater. We redesigned our scheduling system, rescheduled missed patient appointments in a timely fashion and created a process to monitor attendance. This quality improvement work led to a sustained increase in the percentage of patients attending clinic visits four or more times a year reaching our goal of 90% in 2012. Improvements were also noted in the number of patients with body mass index/weight-for-length centile of 25 or greater, which could be related to more frequent clinic attendance.

New stable isotope method to measure protein digestibility and response to pancreatic enzyme intake in cystic fibrosis.

BACKGROUND & AIMS: Adequate protein intake and digestion are necessary to prevent muscle wasting in cystic fibrosis (CF). Accurate and easy-to-use methodology to quantify protein maldigestion is lacking in CF. OBJECTIVE: To measure protein digestibility and the response to pancreatic enzyme intake in CF by using a new stable isotope methodology. DESIGN: In 19 CF and 8 healthy subjects, protein digestibility was quantified during continuous (sip) feeding for 6 h by adding (15)N-labeled spirulina protein and L-[ring-(2)H5]phenylalanine (PHE) to the nutrition and measuring plasma ratio [(15)N]PHE to [(2)H5]PHE. Pancreatic enzymes were ingested after 2 h in CF and the response in protein digestibility was assessed. To exclude difference in mucosal function, postabsorptive whole-body citrulline (CIT) production rate was measured by L-[5-(13)C-5,5-(2)H2]-CIT pulse and blood samples were taken to analyze tracer-tracee ratios. RESULTS: Protein digestibility was severely reduced in the CF group (47% of healthy subjects; P < 0.001). Intake of pancreatic enzymes induced a slow increase in protein digestibility in CF until 90% of values obtained by healthy subjects. Maximal digestibility was reached at 100 min and maintained for 80 min. Stratification into CF children (n = 10) and adults showed comparable values for protein digestibility and similar kinetic responses to pancreatic enzyme intake. Whole-body citrulline production was elevated in CF indicating preserved mucosal function. CONCLUSION: Protein digestibility is severely compromised in patients with CF as measured by this novel and easy-to-use stable isotope approach. Pancreatic enzymes are able to normalize protein digestibility in CF, albeit with a severe delay. Registration ClinicalTrials.gov = NCT01494909.