Evaluation of a multidimensional cystic fibrosis transition program: a quality improvement initiative.

The adequate preparation of cystic fibrosis (CF) youth for the transfer from pediatric to adult-based health care services is essential to meet the needs of this changing population. This paper describes the evolution of a transition clinic for patients with CF into a multidimensional quality improvement transition initiative. Three transition interventions (a patient transition clinical pathway; collaboration with the adult clinic; and a tool to measure transfer readiness) were sequentially implemented and evaluated. Each was found to be a valuable addition to a comprehensive transition protocol and today are endorsed as part of transition best practices.

Effects of a Pseudomonas aeruginosa eradication policy in a cystic fibrosis clinic.

PURPOSE OF REVIEW: This review is based upon the recent literature regarding eradication of newly acquired infection with Pseudomonas aeruginosa (Psa) in patients with cystic fibrosis (CF) and the economic and other effects of such an early eradication policy in a CF clinic. RECENT FINDINGS: Various Psa eradication protocols which utilize intravenous or aerosol anti-pseudomonal antibiotics, with or without oral antibiotics, have been reported. The recent ELITE trial reported successful eradication of 90% of Psa in selected Psa antibody negative patients after 28 days of tobramycin for inhalation. Another recent report of a protocol based on intravenous antibiotic use reported elimination of 'first growth' Psa in over 96% of all patients, accompanied by decreased chronic Psa infection, decreased anti-Psa treatment costs and decreased hospitalization costs. SUMMARY: The effects of early eradication protocols for Psa have included decreased prevalence of chronic Psa infection, improved patient health and pulmonary function, and decreased hospital and antibiotic costs.

Mucoid and nonmucoid Burkholderia cepacia complex bacteria in cystic fibrosis infections.

RATIONALE: infection with Burkholderia cepacia complex (BCC) bacteria in cystic fibrosis (CF) is associated with an unpredictable rate of pulmonary decline. Some BCC, but not others, elaborate copious mucoid exopolysaccharide, endowing them with a gross mucoid phenotype, the clinical significance of which has not been described. OBJECTIVES: to determine whether there was a correlation between bacterial mucoid phenotype, as assessed in a semiquantitative manner from plate culture, and severity of disease as assessed by the rate of decline in lung function. METHODS: we performed a retrospective clinical review of 100 patients with CF attending the Vancouver clinics between 1981 and 2007 and analyzed the rate of lung function decline (% predicted FEV(1)). MEASUREMENTS AND MAIN RESULTS: patients infected exclusively with nonmucoid BCC had a more rapid decline in lung function (annual FEV(1) change, -8.51 ± 2.41%) than those infected with mucoid bacteria (-3.01 ± 1.09%; P < 0.05). Linear mixed-effects data modeling revealed a statistically significant inverse association between semiquantitative mucoid exopolysaccharide production and rate of decline of lung function. In vitro incubation of BCC with ceftazidime and ciprofloxacin but not meropenem caused conversion of BCC from mucoid to nonmucoid. CONCLUSIONS: our data suggest an inverse correlation between the quantity of mucoid exopolysaccharide production by BCC bacteria and rate of decline in CF lung function. Certain antibiotics may induce a change in bacterial morphology that enhances their virulence. A simple in vitro test of bacterial mucoidy may be useful in predicting the rate of decline of respiratory function in CF.

Renal function in pediatric cystic fibrosis patients in the first decade of life.

With increasing life expectancy and the need for lung transplantation in the cystic fibrosis (CF) population, there are increasing reports of chronic kidney disease (CKD). However, values for baseline or longitudinal glomerular filtration rate (GFR) as measured by exogenous clearance markers are lacking in this population. Retrospective cross-sectional study in 2 to 18-year-olds cared for at a single CF center who had a GFR measured by plasma disappearance of Technetium-99 m diethylenetriaminepentaacetic acid (mGFR). The primary outcome was evidence of renal dysfunction as defined by CKD stage II or below (mGFR <90 ml/min/1.73 m(2), persistent abnormalities in urinary sediment, abnormal renal imaging). Of 63 patients evaluated, four had apparent renal dysfunction, one demonstrated decreased mGFR, and three others had persistent microscopic hematuria. The mean mGFR was substantially higher (140 ± 24 ml/min/1.73 m(2)) than expected or previously reported for healthy children. We did not demonstrate the presence of significant renal impairment after limited aminoglycoside exposure in the first decade following diagnosis with CF. However, we did document the presence of glomerular hyperfiltration in a significant proportion of our CF patients.

Phthalate metabolites in urine of CF patients are associated with use of enteric-coated pancreatic enzymes.

In metabolomic studies using liquid chromatography mass spectrometry of urine from children with cystic fibrosis (CF), high levels of metabolites of low molecular weight phthalates were found. Phthalate metabolite excretion was explained by therapy with enteric-coated pancreatic enzyme replacements. Phthalate metabolite identity was confirmed by tandem mass spectrometry. Pancreatic insufficient CF children taking Cotazym ECS(®), which is formulated with diethyl phthalate (DEP), had urinary metabolites of DEP. Children taking Creon(®), which has dibutyl phthalate (DBP), excreted DBP metabolites. The estimated concentrations of free MEP were 2-3 orders of magnitude higher than reported from environmental phthalate exposure. Enteric-coated pancreatic enzymes can expose individuals with CF to incessant, high oral intakes of phthalates. Although adverse effects have neither been shown to be present nor absent, we raise the need to consider that individuals requiring life-long therapy with some current pancreatic enzyme replacements chronically ingest high amounts of phthalates.

Monitoring of serum prolactin in pediatric patients with cystic fibrosis who are receiving domperidone.

BACKGROUND: Since 2003, it has been routine practice at Children's and Women's Health Centre of British Columbia to monitor serum levels of prolactin in pediatric patients with cystic fibrosis who are receiving domperidone. Although a pharmacologic relationship between domperidone and prolactin has been documented in the literature, there is no information about routine monitoring of prolactin, and guidance on interpretation of prolactin values is lacking. OBJECTIVES: To characterize how prolactin levels were being used in monitoring patients with cystic fibrosis who were receiving domperidone therapy at this institution, to evaluate the need for this practice, and to formulate recommendations accordingly. METHODS: A chart review was conducted for pediatric patients with cystic fibrosis who had been receiving domperidone therapy and whose serum prolactin levels had been monitored between June 1, 2001, and October 1, 2005. RESULTS: A total of 219 samples had been drawn, from 49 patients, for determination of prolactin level. Of these, 100 (45.7%) were above the normal range. Of the values above the normal range, 86 (86%) led to no dosage adjustment of domperidone and 14 (14%) led to either a decrease in dose or discontinuation of therapy. None of the elevated prolactin levels were associated with supratherapeutic doses of domperidone. CONCLUSION: The role of routine monitoring of prolactin in this patient population requires further study. In particular, more information is needed about prolactin levels in pediatric patients and the relationship of prolactin level to domperidone dose.

Delays in diagnosing cystic fibrosis: can we find ways to diagnose it earlier?

OBJECTIVE: To describe the clinical presentation and delays in diagnosis of patients with cystic fibrosis (CF) with the goal of raising physicians' awareness of CF and establishing baseline data for comparison with outcomes of patients who undergo newborn screening for CF. DESIGN: Retrospective review of hospital medical records and CF clinic charts of newly diagnosed CF patients younger than 18 years who had attended the CF clinic at the BC Children's Hospital in Vancouver between January 1, 1993, and January 1, 2005. Age at diagnosis of CF was ascertained for 24 adult patients diagnosed during the same period from the CF clinic at St Paul's Hospital in Vancouver, BC. SETTING: Cystic fibrosis clinic at the BC Children's Hospital. PARTICIPANTS: All newly diagnosed CF patients from mainland BC and northern Vancouver Island (N = 122). MAIN OUTCOME MEASURES: Mean age at diagnosis; mean delay in diagnosis; weight and height or length at diagnosis; vitamin E status; mean head circumference; types of symptoms before diagnosis; Pseudomonas aeruginosa status; and number of days spent in tertiary care hospitals before diagnosis. RESULTS: Excluding the adult patients and patients with meconium ileus, mean age at diagnosis of CF was 3.6 years, and mean delay in diagnosis after first symptoms was 2.1 years. Weight at diagnosis was < or = 5th percentile in 37% of cases, and height or length was < or = 5th percentile in 26% of cases. Excluding those with meconium ileus and those taking vitamin E supplementation, 70% of the children were vitamin E deficient at diagnosis. These children had a mean head circumference substantially smaller than that of children who had adequate levels of vitamin E. About 95% of children had gastrointestinal (GI) or malnutrition symptoms before diagnosis; 15% had GI symptoms only. About 81% of patients had respiratory symptoms, but only 4% had respiratory symptoms as the only evidence of CF before diagnosis. Around 9% were colonized with P aeruginosa at diagnosis. Before being diagnosed, 79% of patients had required tertiary care hospitalization for a group total of 320 hospital days. CONCLUSION: Considerable delays in diagnosis of children with CF occur when the disease is identified solely on clinical presentation. Morbidity is often severe enough to require hospital admission before CF is diagnosed. Symptoms that occurred before diagnosis were often GI or malnutritional in nature rather than respiratory, but all such symptoms were associated with diagnostic delays.

Choline-related supplements improve abnormal plasma methionine-homocysteine metabolites and glutathione status in children with cystic fibrosis.

BACKGROUND: Liver triacylglycerol accumulation and oxidative stress are common in cystic fibrosis (CF) and also occur in choline deficiency. Previously, we showed an association between elevated plasma homocysteine, reduced ratios of S-adenosylmethionine to S-adenosylhomocysteine (SAM:SAH) and of phosphatidylcholine to phosphatidylethanolamine, and phospholipid malabsorption in children with CF. OBJECTIVE: The objective was to address a possible relation between altered methionine-homocysteine metabolism and choline metabolism in children with CF. DESIGN: Children with CF were assigned without bias to supplementation with 2 g lecithin/d (n = 13), 2 g choline/d (n = 12), or 3 g betaine/d (n = 10) for 14 d. Plasma concentrations of methionine, adenosine, cysteine, cysteinyl-glycine, glutathione, glutathione disulfide (GSSG), and fatty acids; SAM:SAH; and red blood cell phospholipids were measured within each group of children with CF before and after supplementation. Plasma from healthy children without CF (n = 15) was analyzed to obtain reference data. RESULTS: Children with CF had higher plasma homocysteine, SAH, and adenosine and lower methionine, SAM:SAH, and glutathione:GSSG than did children without CF. Supplementation with lecithin, choline, or betaine resulted in a significant increase in plasma methionine, SAM, SAM:SAH, and glutathione:GSSG and a decrease in SAH (n = 35). Supplementation with choline or betaine was associated with a significant decrease in plasma SAH and an increase in SAM:SAH, methionine, and glutathione:GSSG. Supplementation with lecithin or choline also increased plasma methionine and SAM. CONCLUSION: We showed that dietary supplementation with choline-related compounds improves the low SAM:SAH and glutathione redox balance in children with CF.

Phosphatidylcholine and lysophosphatidylcholine excretion is increased in children with cystic fibrosis and is associated with plasma homocysteine, S-adenosylhomocysteine, and S-adenosylmethionine.

BACKGROUND: Hepatic steatosis and fat malabsorption are common in cystic fibrosis (CF). Choline deficiency results in decreased phosphatidylcholine synthesis through the cytidine diphosphocholine-choline pathway and hepatic steatosis and in increased synthesis of phosphatidylcholine from phosphatidylethanolamine using methyl groups from S-adenosylmethionine. The intestinal absorption of phosphatidylcholine in CF is unknown. OBJECTIVES: The objective was to determine whether excretion of choline phosphoglyceride (phosphatidylcholine and lysophosphatidylcholine) is increased in CF and whether loss of fecal choline phosphoglyceride is associated with altered plasma methionine cycle metabolites. DESIGN: A cross-sectional study involved 53 children with CF and 18 control children without CF. Blood was collected from all participants. A subset of 18 children with CF and 8 control children provided 72-h fecal samples and 5-d food records. RESULTS: Fat absorption was significantly lower (x+/- SEM: 86.2 +/- 1.6% and 94.1 +/- 1.2%) and excretion of fecal fat (12.9 +/- 1.7 and 3.9 +/- 0.7 g/d), phospholipid (median: 130 and 47.7 mg/d), phosphatidylcholine (19.6 and 2.1 mg/d), and lysophosphatidylcholine (60.3 and 16.9 mg/d) was significantly higher in children with CF than in control children, respectively (P < 0.05). Choline phosphoglyceride excretion was positively correlated with plasma homocysteine and S-adenosylhomocysteine and inversely related with plasma methionine (P < 0.05). CONCLUSIONS: Choline phosphoglyceride excretion is increased in children with CF and is associated with decreased plasma methionine and increased homocysteine and S-adenosylhomocysteine. These findings suggest choline depletion and an increased choline synthesis by S-adenosylmethionine-dependent methylation in CF, as well as a metabolic link between phosphatidylcholine metabolism and the methionine-homocysteine cycle in humans.

Economic effects of an eradication protocol for first appearance of Pseudomonas aeruginosa in cystic fibrosis patients: 1995 vs. 2009.

BACKGROUND: Acquisition of Pseudomonas aeruginosa (Psa) and infection with mucoid strains is associated with repeated pulmonary exacerbations which often require intravenous and long-term nebulised antibiotic treatments, repeated hospitalizations and leads to a more precipitous decline in lung function. Anti-Psa antibiotic therapy early in the course of Psa infection in patients with cystic fibrosis (CF) may result in eradication of Psa and prevention or delay of colonization with the organism. From January 1995 to December 2009 our paediatric CF clinic has followed an early eradication protocol for the first appearance of Psa. In this paper we report on the economic effects after 15 years as reflected in hospitalization and antibiotic usage and cost. METHODS: The Psa-eradication protocol includes 2 weeks of IV piperacillin and tobramycin, followed by oral ciprofloxacin for 3 weeks, and nebulised colistimethate for 6 months. The same protocol is used for newly diagnosed CF patients who grow Psa on their first visit or who grow a mucoid strain, multiresistant strain of Psa or whose Psa co-cultured with Burkholderia cepacia complex, and for patients in whom Psa recurs after initial clearance. RESULTS: 195 Psa eradication courses were completed from 1995 to 2009 with an overall Psa clearance rate of 90%. Patients that only cultured a Psa classic (non-mucoid) strain had a clearance rate was 96.5%. The percentage of children chronically infected with Psa has declined from 44% in 1994 to 15% in 2009.Total days spent in hospital for all reasons declined by 43%; chronic Psa hospital days declined by 75%; IV and nebulised anti-Psa antibiotic costs reduced by 44%. CONCLUSIONS: Results indicate that application of a Pseudomonas eradication protocol as described in this report has economic and resource utilization benefits in addition to clinical benefits.

Plasma choline depletion is associated with decreased peripheral blood leukocyte acetylcholine in children with cystic fibrosis.

BACKGROUND: Choline is an important constituent of acetylcholine. Choline is needed for acetylcholine in the nonneuronal acetylcholine system that includes epithelial cells of the lung and intestine, endothelial cells, and immune cells. Plasma free choline concentrations are low in children with cystic fibrosis (CF), but the implications for acetylcholine are unknown. OBJECTIVE: We determined the relation between plasma free choline and related metabolites and leukocyte acetylcholine in children with CF and in a control group of healthy children without CF. DESIGN: This was a cross-sectional study in 34 children with CF who were pancreatic insufficient and taking pancreatic enzyme-replacement therapy and in 16 healthy children. Plasma free choline, betaine, dimethylglycine, methionine, homocysteine, and leukocyte acetylcholine concentrations were quantified by using isotope-dilution HPLC-tandem mass spectrometry. RESULTS: Mean (±SE) plasma free choline was 9.30 ± 0.37 and 6.54 ± 0.38 µmol/L (P < 0.05) and leukocyte acetylcholine was 1.21 ± 0.016 and 0.077 ± 0.011 pmol leukocyte acetylcholine/10(6) cells (P < 0.05) in control children and children with CF, respectively. Leukocyte acetylcholine was positively correlated with plasma free choline concentration in children with CF (r = 0.412, P < 0.05) but not in control children. Plasma betaine, dimethylglycine, and methionine concentrations were also lower in children with CF than in control children (P < 0.05). CONCLUSIONS: A low free choline and methyl status in children with CF is associated with reduced acetylcholine in leukocytes. Whether these changes are explained by a mutation in the CF transmembrane conductance regulator or disturbances in choline metabolism and the implications for immune cell dysfunction in CF are unknown. This trial was registered at clinicaltrials.gov as NCT01150136.

Cystic fibrosis and nutrition: linking phospholipids and essential fatty acids with thiol metabolism.

Cystic fibrosis (CF) is the most common lethal inherited disorder among Caucasians and results from mutation in the gene encoding the CF transmembrane conductance regulator. In addition to its multisystem clinical effects, the disease is characterized by increased proinflammatory mediators and oxidant stress, and systemic redox imbalance with reduced glutathione (GSH), together with alterations in circulating and tissue (n-6) and (n-3) fatty acids, particularly a decrease in docosahexaenoic acid. The metabolism of phospholipids and fatty acids is closely related to GSH through the methionine-homocysteine cycle, in which choline via betaine provides methyl groups to regenerate S-adenosylmethionine, important in generating phosphatidylcholine and amino acid precursors for GSH. Current research focuses both on fatty acid supplementations to normalize altered (n-6) to (n-3) fatty acid balance and decrease generation of (n-6) fatty acid-derived inflammatory mediators, and strategies to improve oxidant defenses and redox balance. However, further research is needed before such strategies can be included in clinical care of individuals with CF.

Innate immunity mediated by TLR5 as a novel antiinflammatory target for cystic fibrosis lung disease.

Novel therapies to target lung inflammation are predicted to improve the lives of people with cystic fibrosis (CF) but specific antiinflammatory targets have not been identified. The goal of this study was to establish whether TLR5 signaling is the key molecular pathway mediating lung inflammation in CF, and to determine whether strategies to inhibit TLR5 can reduce the damaging inflammatory response. The innate immune responses were analyzed in both airway epithelial cells and primary PBMCs from CF patients and matched controls. Additionally, 151 clinical isolates of Pseudomonas aeruginosa from CF patients were assessed for motility and capacity to activate TLR5. Blood and airway cells from CF patients produced significantly more proinflammatory cytokine than did control cells following exposure to the CF pathogens P. aeruginosa and Burkholderia cepacia complex (p < 0.001). Stimulation with pure TLR ligands demonstrated that TLR signaling appears to mediate the excessive cytokine production occurring in CF. Using complementary approaches involving both neutralizing Ab targeting TLR5 and flagellin-deficient bacteria, we established that inhibition of TLR5 abolished the damaging inflammatory response generated by CF airway cells following exposure to P. aeruginosa (p < 0.01). The potential therapeutic value of TLR5 inhibition was further supported by our demonstration that 75% of clinical isolates of P. aeruginosa retained TLR5 activating capacity during chronic CF lung infection. These studies identify the innate immune receptor TLR5 as a novel antiinflammatory target for reducing damaging lung inflammation in CF.

Increased plasma homocysteine and S-adenosylhomocysteine and decreased methionine is associated with altered phosphatidylcholine and phosphatidylethanolamine in cystic fibrosis.

OBJECTIVE: We used a novel approach based on the intersection of phospholipid and methionine metabolism at the S-adenosylmethionine (SAM)-dependent methylation of phosphatidylethanolamine (PE) to study potential alterations in phospholipid metabolism in children with cystic fibrosis (CF). Methyl groups from methionine via SAM are used for sequential methylation of PE to form phosphatidylcholine (PC) with the generation of S-adenosylhomocysteine (SAH) and homocysteine. STUDY DESIGN: Plasma phospholipids and methionine metabolites and plasma and red blood cell phospholipid fatty acids were determined in 53 children with CF and 18 control children. RESULTS: Plasma methionine and the PC/PE ratio was lower and homocysteine, SAH, and PE were higher in children with CF than in control children (P<.001). Plasma methionine was inversely (P<.05) and SAH and homocysteine were positively (P<.001) correlated with the plasma PE. Docosahexaenoic acid (22:6n-3) was significantly lower in plasma phospholipids and triglycerides and in red blood cell PC and PE of children with CF than in control children (P<.05). CONCLUSIONS: These studies demonstrate that methionine metabolism is altered and associated with alteration of the plasma PC/PE ratio in CF. Altered phospholipid and methionine metabolism may contribute to the clinical complications associated with CF.

Epidemiology of Pseudomonas aeruginosa in cystic fibrosis in British Columbia, Canada.

Pseudomonas aeruginosa is the most common respiratory pathogen in patients with cystic fibrosis (CF), but the predominant mechanism by which it is acquired is controversial. To determine the frequency of patient-to-patient spread, we evaluated P. aeruginosa isolates from 174 patients treated at the CF clinics in Vancouver, BC, Canada, since 1981. Multiple isolates were obtained from each patient and genetically typed by random amplified polymorphic DNA and pulsed field gel electrophoresis analyses. A total of 157 genetic types of P. aeruginosa was identified, 123 of which were unique to individual patients. A total of 34 types was shared by more than one patient; epidemiologic evidence linked these individuals only in the cases of 10 sibships and 1 pair of unrelated patients. We conclude that there is an extremely low risk in Vancouver for patients with CF to acquire P. aeruginosa from other patients. It appears that prolonged close contact, such as occurs between siblings, is necessary for patient-to-patient spread. The major source of acquisition of P. aeruginosa in CF appears to be from the environment. Considering these observations, we do not recommend segregation of patients with CF on the basis of their colonization status with P. aeruginosa.

Alpha 1-antitrypsin deficiency alleles in cystic fibrosis lung disease.

Cystic fibrosis (CF) transmembrane conductance regulator (CFTR) genotype does not explain the heterogeneity observed in CF pulmonary disease severity. Modifier genes are implicated for this heterogeneity. alpha1-antitrypsin (alpha1-AT) is one of the few antiproteases capable of inactivating neutrophil elastase. We investigated whether alpha1-AT alleles (Z, S deficiency alleles and the 3' G1237-->A mutation) were associated with increased disease severity and the alpha1-AT acute phase response during pulmonary exacerbations. This was a multicenter Canadian study. Seven hundred sixteen patients with CF (age range, 5.0-63.6 yr) were genotyped for the Z, S, and G1237-->A polymorphisms of the alpha1-AT gene. Stable and acute levels of alpha1-AT were measured on 31 adult patients with CF and were correlated to clinical parameters. There were 69, 13, and 18 patients with CF who were MS, SS, and MZ, respectively. There were 95 and 7 patients with CF heterozygous or homozygous for the A1237 allele, respectively. alpha1-AT genotype did not predict pulmonary disease severity, and was not associated with more severe clinical outcome (death or lung transplantation) or age of onset of Pseudomonas aeruginosa infection. Body mass index was a significant predictor of alpha1-AT levels during exacerbations. alpha1-AT genotype is not a major contributor to the variability of pulmonary disease severity in CF.