Fibrosis Transmembrane Conductance Regulator Mutations Research Articles

Report of two patients with associated conditions in addition to cystic fibrosis

Purpose To report two patients with associated conditions in addition to cystic fibrosis. Methods We reviewed our database and report two patients with cystic fibrosis who had associated conditions. These patients also had novel disease causing CFTR mutations on full gene sequence analysis. Results We identified 2 patients with novel disease causing cystic fibrosis transmembrane conductance regulator mutations that we report here. A 12-year-old female with cystic fibrosis, diagnosed at 18 months, had normal pulmonary function tests and chest X-ray. Her main cystic fibrosis-related health issue was poor growth. Results of cystic fibrosis transmembrane conductance regulator DNA analysis showed deltaF508; L467P; and 7T/9T. She was later diagnosed with Crohn's disease. An 11-year-old male with Rubinstein–Taybi syndrome, diagnosed with cystic fibrosis at 2 years of age, had minimal findings on chest X-ray and pancreatic insufficiency. Results of his cystic fibrosis transmembrane conductance regulator DNA analysis showed deltaF508; 4329delCT; and 7T/9T. Conclusion We report 2 patients with CF who had associated conditions and also had novel disease causing CFTR mutations. Associated conditions may worsen the clinical manifestations of CF and complicate medical management.

CFTR Depletion Results in Changes in Fatty Acid Composition and Promotes Lipogenesis in Intestinal Caco 2/15 Cells

BackgroundAbnormal fatty acid composition (FA) in plasma and tissue lipids frequently occurs in homozygous and even in heterozygous carriers of cystic fibrosis transmembrane conductance regulator (CFTR) mutations. The mechanism(s) underlying these abnormalities remained, however, poorly understood despite the potentially CFTR contributing role.Methodology/Principal FindingsThe aim of the present study was to investigate the impact of CFTR depletion on FA uptake, composition and metabolism using the intestinal Caco-2/15 cell line. shRNA-mediated cftr gene silencing induced qualitative and quantitative modifications in FA composition in differentiated enterocytes as determined by gas-liquid chromatography. With the cftr gene disruption, there was a 1,5 fold increase in the total FA amount, largely attributable to monounsaturated and saturated FA compared to controls. The activity of delta-7 desaturase, estimated by the 16:1(n-7)/16:0, was significantly higher in knockdown cells and consistent with the striking elevation of the n-7 FA family. When incubated with [14C]-oleic acid, CFTR-depleted cells were capable of quick incorporation and export to the medium concomitantly with the high protein expression of L-FABP known to promote intracellular FA trafficking. Accordingly, lipoprotein vehicles (CM, VLDL, LDL and HDL), isolated from CFTR knockdown cells, exhibited higher levels of radiolabeled FA. Moreover, in the presence of [14C]-acetate, knockdown cells exhibited enhanced secretion of newly synthesized phospholipids, triglycerides, cholesteryl esters and free FA, thereby suggesting a stimulation of the lipogenic pathway. Conformably, gene expression of SREBP-1c, a key lipogenic transcription factor, was increased while protein expression of the phosphorylated and inactive form of acetylCoA carboxylase was reduced, confirming lipogenesis induction. Finally, CFTR-depleted cells exhibited lower gene expression of transcription factors (PPARα, LXRα, LXRβ and RXRα).Conclusions/SignificanceCollectively, our results indicate that CFTR depletion may disrupt FA homeostasis in intestinal cells through alterations in FA uptake and transport combined with stimulation of lipogenesis that occurs by an LXR/RXR-independent mechanism. These findings exclude a contributing role of CFTR in CF-associated fat malabsorption.

Risk factors for allergic bronchopulmonary aspergillosis in paediatric patients with cystic fibrosis

<h3>Introduction</h3> Allergic bronchopulmonary aspergillosis (ABPA) is increasingly prevalent among cystic fibrosis (CF) patients. Atopy, sex, season at diagnosis and cystic fibrosis transmembrane conductance regulator (CFTR) mutation are suggested risk factors for ABPA. Studies indicate that centres using a high amount of intravenous antibiotics have better outcomes, but this has also been linked to the increase in ABPA. The objective of this retrospective case-control study was to assess potential risk factors for ABPA, in particular intravenous antibiotic use. <h3>Methods</h3> Of 150 paediatric patients, 13 fulfilled the CF foundation consensus diagnostic criteria for ABPA. These were compared to 130 patients without evidence of ABPA. Seven patients were excluded from the study as they showed evidence of ABPA but did not fulfil the diagnostic criteria. The intravenous antibiotic data for the ABPA group was compared to 80 patients without ABPA using extended matching by age of diagnosis. The data collected included age, sex, CFTR mutation, atopy (history or family history of diagnosed hay fever, eczema or asthma), and weeks of intravenous antibiotics administered. Season of diagnosis was noted for the ABPA group. <h3>Results</h3> The median duration of use of intravenous antipseudomonal antibiotics in the ABPA group was 38 weeks, compared to 5 weeks in the non-ABPA group (p&lt;0.05). No difference was found in the duration of use of non-antipseudomonal antibiotics (median 12 weeks in ABPA group, 2 weeks in non-ABPA group). The average time since diagnosis of CF was higher in the ABPA group by 3 years (p=0.01). 12/13 (92%) of ABPA patients had a history of atopy compared to 50/105 (47%) of the non-ABPA group (p=0.05). There was no difference in CFTR mutation, sex or season of ABPA diagnosis. <h3>Conclusion</h3> Intravenous antipseudomonal antibiotic use was substantially higher in the ABPA population. This could be a factor in the increase in ABPA, suggesting that tighter microbiological guidance may be useful before initiating antibiotic treatment. However, this could also be that IV use and ABPA are both markers for increased disease severity. Atopy was also significantly higher in the ABPA population. This could potentially be used to highlight those CF patients at risk from this disease.

Non‐classic cystic fibrosis associated with D1152H CFTR mutation

Limited knowledge exists on phenotypes associated with the D1152H cystic fibrosis transmembrane conductance regulator (CFTR) mutation. Subjects with a D1152H allele in trans with another CFTR mutation were identified using the French Cystic Fibrosis Registry. Phenotypic characteristics were compared with those of pancreatic insufficient (PI) and pancreatic sufficient (PS) cystic fibrosis (CF) subjects in the Registry (CF cohort). Forty-two subjects with D1152H alleles were identified. Features leading to diagnosis included chronic sinopulmonary disease (n = 25), congenital absence of the vas deferens (n = 11), systematic neonatal screening (n = 4), and genetic counseling (n = 2). Median age at diagnosis was 33 [interquartile range (IQR, 24-41)] years in D1152H subjects. Median sweat chloride concentrations were 43.5 (39-63) mmol/l in D1152H subjects and were markedly lower than in PI and PS CF subjects (p < 0.05). Bronchiectasis was present in 67% of D1152H subjects, but Pseudomonas aeruginosa colonization and pancreatic insufficiency were present in <30% of subjects. Estimated rates of decline in forced expiratory volume in 1 s (FEV(1)) were lower in D1152H subjects vs PI CF subjects (p < 0.05). None of the D1152H subjects identified since 1999 had died or required lung transplantation. When present in trans with a CF-causing mutation, D1152H causes significant pulmonary disease, but all subjects had prolonged survival.

Association of cystic fibrosis genetic modifiers with congenital bilateral absence of the vas deferens

To investigate whether genetic modifiers of cystic fibrosis (CF) lung disease also predispose to congenital bilateral absence of the vas deferens (CBAVD) in association with cystic fibrosis transmembrane conductance regulator (CFTR) mutations. We tested the hypothesis that polymorphisms of transforming growth factor (TGF)-β1 (rs 1982073, rs 1800471) and endothelin receptor type A (EDNRA) (rs 5335, rs 1801708) are associated with the CBAVD phenotype. Genotyping of subjects with clinical CBAVD. Outpatient and hospital-based clinical evaluation. DNA samples from 80 subjects with CBAVD and 51 healthy male controls from various regions of Europe. This is one of the largest genetic studies of this disease to date. None. Genotype analysis. For single nucleotide polymorphism (SNP) rs 5335, we found increased frequency of the CC genotype among subjects with CBAVD. The difference was significant among Turkish patients versus controls (45.2% vs. 19.4%), and between all cases versus controls (36% vs. 15.7%). No associations between CBAVD penetrance and polymorphisms rs 1982073, rs 1800471, or rs 1801708 were observed. Our findings indicate that endothelin receptor type A polymorphism rs 5335 may be associated with CBAVD penetrance. To our knowledge, this is the first study to investigate genetic modifiers relevant to CBAVD.

Common CFTR gene variants influence body composition and survival in rural Ghana

Various studies in mice have found support for the hypothesis that heterozygous carriers of cystic fibrosis transmembrane conductance regulator (CFTR) mutations have an increased resistance to fatal infection compared to both homozygous mutation carriers and non-carriers, while in humans such evidence is scarce. In this study, we assessed the CFTR heterozygotes survival advantage hypothesis in a contemporary rural population that lives under adverse environmental conditions in the Upper-East region of Ghana. We genotyped 30 SNPs throughout the CFTR gene in 4,230 participants and tested their influence on survival and on body composition in the population at large. With a sliding-window haplotype analysis, we identified a set of six common haplotypes that influenced survival probabilities (global p = 6.00 × 10−05). Individual haplotype analyses revealed two haplotypes of specific interest. One of these haplotypes was enriched (p = 0.003), whereas the other was depleted (p = 0.041) among people of old age (≥65 years) compared to young study participants (≤5 years). In addition, children (n = 474) carrying the latter haplotype had lower body weight (p trend = 0.020) and height (p trend = 0.010) compared to non-carriers. For all these analyses, similar associations for heterozygous and homozygous CFTR haplotype carriers were observed, revealing an additive effect of haplotype alleles. In conclusion, we identified common haplotypes in the CFTR gene that influence survival and body composition in the population at large with no evidence for heterozygote advantage.Electronic supplementary materialThe online version of this article (doi:10.1007/s00439-009-0762-2) contains supplementary material, which is available to authorized users.

Cystic fibrosis transmembrane conductance regulator mutations in azoospermic and oligospermic men and their partners

The objective of this study was to investigate the contribution of cystic fibrosis transmembrane conductance regulator (CFTR) to human infertility and to define screening and counselling procedures for couples asking for assisted reproduction treatment. Extended CFTR mutation screening was performed in 310 infertile men (25 with congenital absence of the vas deferens (CAVD), 116 with non-CAVD azoospermia, 169 with severe oligospermia), 70 female partners and 96 healthy controls. CFTR mutations were detected in the majority (68%) of CAVD patients and in significant proportions in azoospermic (31%) and oligospermic (22%) men. Carrier frequency among partners of infertile men was 16/70, exceeding that of controls (6/96) significantly (P = 0.0005). Thus, in 23% of infertile couples both partners were carriers, increasing the risk for their offspring to inherit two mutations to 25% or 50%. This study emphasizes the necessity to offer extended CFTR mutation screening and counselling not only to patients with CAVD but also to azoospermic and oligozoospermic men and their partners before undergoing assisted reproduction techniques. The identification of rare and/or mild mutations will not be a reason to abstain from parenthood, but will allow adequate treatment in children at risk for atypical or mild cystic fibrosis as soon as they develop any symptoms.

Cystic Fibrosis Transmembrane Conductance Regulator Mutation Spectrum in Patients with Cystic Fibrosis in Tunisia

To determine the frequency and types of mutations causing cystic fibrosis (CF) in Tunisia. We analyzed the complete coding region and flanking intronic sequences of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in 68 unrelated patients suffering from the classical form of the disease. Twelve different CFTR mutations accounted for 90% (123/136) of CF alleles, including F508del (47.06%), E1104X (16.18%), N1303K (6.62%), 711 + 1T > G (5.88%), W1282X (4.41%), G542X (3.67%), R1158X (1.47%), 4016insT (0.74%), and R785X (0.74%). Three novel mutations were detected in this study: I1203V (1.47%), 1811 + 5A > G (0.74%), and 4268 + 2T > G (1.47%). Fifty patients (74%) were homozygous, among which 28 (41.17%) for F508del and 10 (14.7%) for E1104X. Ninety-seven percent of patients were found with at least one CFTR mutation. This study contributes to a better knowledge on CF-causing mutations in different regions in Tunisia and demonstrates that a complete scanning of CFTR sequences is necessary to implement efficient programs for CF genetic screening and counseling in this part of North Africa.

Protein–energy malnutrition as the first manifestation of cystic fibrosis in infancy

The protein-energy malnutrition (PEM) that is characterized by hypoproteinemia, edema, and anemia has been reported in 5-13% of infants with cystic fibrosis (CF). Due to the surprising higher incidence of PEM as the first presenting manifestation of CF in Macedonia, the aim of the present study was to evaluate the possible risk factors in its development. Clinical and laboratory profiles (hemoglobin, red blood cell count, total serum protein, serum albumin and liver enzyme levels) and genotype data were analyzed in 115 newly diagnosed infants with CF, during the period 1990-2006. PEM manifested in 39 CF infants (33%), usually within the first 5 months of life and in breast-fed infants. Mean hemoglobin, red blood cell count, total serum protein and serum albumin values in the PEM subgroup were, respectively, 76.0 g/L, 2.4 x 10(12)/L, 38.0 g/L and 16.6 g/L. Clinically significant liver involvement was found in 22 patients (56.4%) with PEM. Concerning the molecular basis of CF in these patients, PEM was always associated with triangle upF508, G542X, N1303K and other severe mutations. PEM is a common manifestation of CF in infancy. Early infant age, breast-feeding, impaired liver function and the presence of severe cystic fibrosis transmembrane conductance regulator mutations are predisposing factors for the development of PEM.

Functional characterisation of the CFTR mutations M348V and A1087P from patients with pancreatitis suggests functional interaction between CFTR monomers

In a recent study on the role of cystic fibrosis transmembrane conductance regulator (CFTR) mutations in idiopathic chronic pancreatitis ( Gut 2005; 54 :1456–60) we sequenced the complete CFTR-coding region...

Clarification of Laboratory and Clinical Variables That Influence Cystic Fibrosis Newborn Screening With Initial Analysis of Immunoreactive Trypsinogen

To ensure that each newborn receives an equitable test of the highest possible sensitivity, we recognized the necessity to reassess immunoreactive trypsinogen and DNA issues in cystic fibrosis newborn screening algorithms. Our objectives included clarification of various factors that influence immunoreactive trypsinogen concentrations and resolution of long-standing questions about variations in immunoreactive trypsinogen levels among newborns. Immunoreactive trypsinogen data on 660443 newborns who were born between July 1, 1994, and June 30, 2004, were abstracted from the Wisconsin State Laboratory of Hygiene databases and deidentified for analysis. Using a compiled data set, we analyzed various demographic characteristics to determine their role, if any, in immunoreactive trypsinogen variation. Specifically, season of birth, reagent lot, and birth weight were examined. Sensitivities of the most common cystic fibrosis newborn screening protocols, namely immunoreactive trypsinogen/immunoreactive trypsinogen and immunoreactive trypsinogen/DNA, were also investigated. Mean and 95th percentile immunoreactive trypsinogen levels were shown to vary by both season and reagent lot number and affect sensitivity of the assay. Low birth weight infants had significantly higher immunoreactive trypsinogen values than normal birth weight infants. Sensitivities were also found to vary on the basis of the algorithm used, with the highest sensitivity of 96.2% calculated for an immunoreactive trypsinogen/DNA protocol with 23 cystic fibrosis transmembrane conductance regulator mutation analyses compared with 80.2% with the immunoreactive trypsinogen/immunoreactive trypsinogen method used in 9 states. Floating, rather than fixed, cutoff values for the initial immunoreactive trypsinogen portion of any cystic fibrosis newborn screening protocol are generally necessary on the basis of the seasonal and reagent lot variations observed. Because of its lower sensitivity, immunoreactive trypsinogen/immunoreactive trypsinogen does not optimize detection of patients with cystic fibrosis.

Evaluation of High-Resolution Melting (HRM) for Mutation Scanning of Selected Exons of the CFTR Gene

Hereby we present evaluation of high-resolution melting for mutation scanning applied to the cystic fibrosis transmembrane conductance regulator gene. High resolution melting was used for mutation scanning of selected samples derived from cystic fibrosis patients with a known cystic fibrosis transmembrane conductance regulator genotype. We tested 19 different disease-causing cystic fibrosis transmembrane conductance regulator mutant genotypes located within six exons of the cystic fibrosis transmembrane conductance regulator gene (4, 7, 10, 11, 14b and 22). Normalized melting curves of tested samples were compared to sequenced-verified wildtype samples. Determined mutations are as follows: p.F508del, p.I507del, p.G551D, p.R347P, c.17171G&gt;A, c.621+1G&gt;T, p.Y122X, p.I336K, p.R553X, c.2789+5G&gt;A, c.574delA, c.1811+1G&gt;C, p.L1335F, p.L1335P, p.L1324P and p.M470V and represent minimally 76.5 % of all cystic fibrosis alleles detected in the Czech cystic fibrosis population. All analysed samples with mutant genotypes were unambiguously distinguished from wild-type samples. High-resolution melting analysis enabled reliable detection of all single-nucleotide polymorphism classes and 1or 3-base pair deletions. We examined the specificity, sensitivity and precision of this methodology. High-resolution melting analysis is an economical, sensitive and specific close-tube method and has a high utility for the detection of unknown mutations in cystic fibrosis DNA diagnostics.

The role of the F508C mutation in congenital bilateral absence of the vas deferens

PurposeCongenital bilateral absence of the vas deferens is a pathologic condition associated with normal spermatogenesis, azoospermia, and lack of both vasa deferentia. A significant association between mutations in the cystic fibrosis transmembrane conductance regulator gene among men with congenital bilateral absence of the vas deferens has been established. The objective of this study was to determine whether the F508C variant in the cystic fibrosis transmembrane conductance regulator gene has a significant effect on congenital bilateral absence of the vas deferens prevalence, when present in conjunction with a second cystic fibrosis transmembrane conductance regulator disease causing mutation. Methods and ResultsWe compared the frequency of F508C in male subjects submitted for diagnostic testing on suspicion of cystic fibrosis or during cystic fibrosis carrier screening, to men with a clinical diagnosis of congenital bilateral absence of the vas deferens. Although frequencies of F508C did not vary significantly between 850 individuals undergoing cystic fibrosis carrier screening and those submitted for diagnostic testing on suspicion of cystic fibrosis, the frequency of F508C in the congenital bilateral absence of the vas deferens population was significantly higher than expected (χ2 = 6.95, corrected P = 0.0486). ConclusionWe conclude that the F508C variant in cystic fibrosis transmembrane conductance regulator may represent a pathogenic defect and lead to congenital bilateral absence of the vas deferens when combined with a second cystic fibrosis transmembrane conductance regulator mutation.

Pulmonary Nontuberculous Mycobacterial Disease

Pulmonary nontuberculous mycobacterial (PNTM) disease is increasing, but predisposing features have been elusive. To prospectively determine the morphotype, immunophenotype, and cystic fibrosis transmembrane conductance regulator genotype in a large cohort with PNTM. We prospectively enrolled 63 patients with PNTM infection, each of whom had computerized tomography, echocardiogram, pulmonary function, and flow cytometry of peripheral blood. In vitro cytokine production in response to mitogen, LPS, and cytokines was performed. Anthropometric measurements were compared with National Health and Nutrition Examination Survey (NHANES) age- and ethnicity-matched female control subjects extracted from the NHANES 2001-2002 dataset. Patients were 59.9 (+/-9.8 yr [SD]) old, and 5.4 (+/-7.9 yr) from diagnosis to enrollment. Patients were 95% female, 91% white, and 68% lifetime nonsmokers. A total of 46 were infected with Mycobacterium avium complex, M. xenopi, or M. kansasii; 17 were infected with rapidly growing mycobacteria. Female patients were significantly taller (164.7 vs. 161.0 cm; P < 0.001) and thinner (body mass index, 21.1 vs. 28.2; P < 0.001) than matched NHANES control subjects, and thinner (body mass index, 21.1 vs. 26.8; P = 0.002) than patients with disseminated nontuberculous mycobacterial infection. A total of 51% of patients had scoliosis, 11% pectus excavatum, and 9% mitral valve prolapse, all significantly more than reference populations. Stimulated cytokine production was similar to that of healthy control subjects, including the IFN-gamma/IL-12 pathway. CD4(+), CD8(+), B, and natural killer cell numbers were normal. A total of 36% of patients had mutations in the cystic fibrosis transmembrane conductance regulator gene. Patients with PNTM infection are taller and leaner than control subjects, with high rates of scoliosis, pectus excavatum, mitral valve prolapse, and cystic fibrosis transmembrane conductance regulator mutations, but without recognized immune defects.

Modulation of cystic fibrosis lung disease by variants in interleukin-8

Cystic fibrosis pulmonary disease is characterized by excessive and prolonged inflammation. CF Pulmonary disease severity exhibits considerable variation that, to some extent, appears to be due to the presence of modifier genes. Several components of the inflammatory response are known to have altered regulation in the CF lung. Genetic variants in 52 inflammatory genes were tested for associations with lung disease indices in a CF patient population (n=737) homozygous for the DeltaF508 cystic fibrosis transmembrane conductance regulator mutation. Variants in three inflammatory genes showed significant genotypic associations with CF lung disease severity, including IL8 and previously reported TGFbeta1 (P< or =0.05). When analyzed by gender, it was apparent that IL8 variant associations were predominantly due to males. The IL8 variants were tested in an additional CF population (n=385) and the association in males verified (P< or =0.01). The IL8 variants were in strong linkage disequilibrium with each other (R2> or =0.82), while variants in neighboring genes CXCL6, RASSF6 and PF4V1 did not associate (P> or =0.26) and were in weaker LD with each other and with the IL8 variants (0.01< or =R2< or =0.49). Studies revealed differential expression between the IL8 promoter variant alleles (P<0.001). These results suggest that IL8 variants modify CF lung disease severity and have functional consequences.

Susceptibility to nontuberculous mycobacterial lung disease: Table 1—

The nontuberculous mycobacteria (NTM) exhibit heterogeneous pathogenicity in humans. Articles on known and potential human factors capable of producing susceptibility to NTM lung disease (NTMLD) were identified by a systematic search of the medical literature, and are reviewed in the present study. Patients with pre-existing structural lung disease are known to be at risk of NTMLD. Other susceptible groups have become recognised since the 1980s, in particular middle-aged nonsmokers without previous lung disease (a group including those with Lady Windermere syndrome) and patients with genetically determined defects of cell-mediated immunity, including abnormalities of the interleukin-12/interferon-gamma axis, certain human leukocyte antigen alleles, cystic fibrosis transmembrane conductance regulator mutations, and polymorphisms of solute carrier 11A1 (or natural resistance-associated macrophage protein 1) and the vitamin D receptor. Information is also accruing about acquired systemic causes of susceptibility to NTMLD, including inhibitory antibodies directed against interferon-gamma, post-menopausal waning of endogenous oestrogen levels, coeliac disease and exposure to use of dietary phyto-oestrogens. It is not known whether immunosuppressive factors, such as oral corticosteroid treatment, chronic renal failure, diabetes mellitus and other known risk factors for pulmonary tuberculosis, are also risk factors for the development of NTMLD. Caution is appropriate in managing such patients.

Sequence analyses of presenilin mutations linked to familial Alzheimer’s disease

Familial Alzheimer's disease (FAD)-linked presenilin (PS) mutations show gain-of-toxic-function characteristics. These FAD PS mutations are scattered throughout the PS molecule, reminiscent of the distribution of cystic fibrosis transmembrane conductance regulator and p53 mutations. Because of the scattered distribution of PS mutations, it is difficult to infer mechanistic insights about how these mutations cause the disease similarly. Recent careful reexamination of gamma-secretase activity indicates that some PS mutations decrease the proteolytic activity of gamma-secretase, suggesting a loss-of-function nature of PS mutations. To extend this observation to all known PS mutations, a large number of PS mutations were evaluated using bioinformatic tools. The analyses reveal that as many as one third of PS1 residues are highly conserved, that about 75% of FAD mutations are located to the highly conserved residues, and that most PS mutations likely damage the activity of PS. These results are consistent with the idea that the majority of PS mutations lower the activity of PS/gamma-secretase.

The effect of bile acids on human pancreatic duct cells

We have previously shown that exposure of intact guinea pig pancreatic ducts to bile acids, which may occur e.g. in acute pancreatitis, induces intracellular acidification and a marked increase in intracellular Ca2+ concentration ([Ca2+]i). Moreover, a low dose of chenodeoxycholate (CDC) stimulates the luminal anion exchanger which suggests a possible role of cystic fibrosis transmembrane conductance regulator (CFTR) in this effect. There are no available data concerning the effect of bile acids on human pancreatic duct cells. The aim of our study was to examine the effects of CDC or glycochenodeoxycholate (GCDC) in human cystic fibrosis CFPAC-1 pancreatic duct cells which are homozygous for the most common delF508 cystic fibrosis transmembrane conductance regulator (CFTR) mutation or in CFPAC-1 cells which are corrected for the defective CFTR. Methods: We transduced polarized CFPAC-1 cells (n=4–6) with recombinant Sendai virus (SeV) constructs (multiplicity of infection=3) containing the CFTR or β-galactosidase (LacZ) cDNA. 48–72h after infection, the intracellular pH (pHi) and [Ca2+]i of the cells were recorded by microfluorimetry. Results: Both apical and basolateral administration of CDC or GCDC caused dose-dependent (100–1000µM) reversible intracellular acidification. Our results did not show significant differences in the rate of intracellular acidification caused by bile acids in SeV-CFTR and SeV-LacZ transduced cells. The exposure of cell lines to bile acids induced a marked increase in [Ca2+]i and CDC caused the largest response. Similarly to that observed in primary ducts, the effect of CDC administration from the apical membrane was greater than from the basolateral membrane. Furthermore, glycine conjugated bile acids also resulted in Ca2+ signalling when administered from either membrane of the cells. Conclusions: Human pancreatic duct cells respond similarly to administration of bile acids compared to that observed in guinea pigs. CFTR expression is not necessary for pHi changes and Ca2+ signalling caused by bile acids.

Two cases of extraordinary chronic rhinosinusitis in pediatrics: Take care of antibiotic overprescribing in primary care

Two cases of pediatric chronic rhinosinusitis with Pseudomonas aeruginosa as pathogen organism are presented. Both children had gastroesophageal reflux and one of them was allergic. The results of sweat test were within normal limits. Cystic fibrosis transmembrane conductance regulator mutations were not identified in the patients. They had been treated a lot of times with antimicrobial agents with the diagnosis of respiratory tract infection. We suggest that the frequent use of antibiotics has led to the selective suppression and as a result P. aeruginosa has been detected as the cause of chronic rhinosinusitis in otherwise healthy children.

Growth and nutritional status in children and adolescents with cystic fibrosis

Background: Growth retardation, delayed puberty and malnutrition are frequently observed in children suffering from cystic fibrosis.Aim: The aim of this study was to estimate growth and nutritional status in children with cystic fibrosis on the basis of body proportions and body mass index.Subjects and methods: Anthropometric data were collected from the medical histories of 62 patients treated in three cystic fibrosis treatment centers in Poland. Anthropometric parameters were expressed in terms of standard deviations away from age-specific and sex-specific reference means reported for the population of Poland. Two-way analysis of variance was used to determine whether the type of cystic fibrosis transmembrane conductance regulator (CFTR) mutation is correlated with age at the time of diagnosis and with body proportions.Results: The type of mutation was significantly correlated with height, weight and transverse chest width. Growth retardation was greater in subjects diagnosed before they were 3 years old than in subjects diagnosed later. The children had infantile body proportions. Their legs were short and their trunks were long in comparison to their height. Almost 40% of the subjects suffered from malnourishment.Conclusion: Further study is needed to determine how growth in children with cystic fibrosis is affected by clinical practice and socio-economic factors.