Non-cystic Fibrosis Patients Research Articles

TGF-beta 1 downregulates CFTR expression and function in nasal polyps of non-CF patients.

Nasal polyposis is a chronic inflammatory disease of the upper airways. It has been suggested that ion transports and CFTR expression could be modified in epithelial cells from nasal polyps of non-cystic fibrosis patients. We compared human nasal epithelial cells from nasal polyps (NP) with control nasal mucosa (CM). The level of CFTR mRNA was studied by Northern blot analysis and protein expression was studied by immunoprecipitation both ex vivo and in vitro in primary cultures of human nasal epithelial cells at the air-liquid interface. Ion transports were evaluated by short-circuit measurements in vitro. CFTR gene and protein expressions were significantly decreased in NP native tissues and in culture on day 4, when a global defect of ion transports was observed in NP cultures, but not in CM. We evaluated the effect of transforming growth factor (TGF)-beta 1 on CFTR expression and function in NP cultures on day 14 and showed, for the first time, that TGF-beta 1 was able to significantly downregulate the level of CFTR mRNA and cAMP-dependent current in NP cultures. Finally, we showed that the effects of TGF-beta 1 on ion transports could be reversed after 48-h removal of TGF-beta1 in NP cultures. In conclusion, our data strongly suggest that chronic inflammation in nasal polyposis downregulates CFTR gene and protein expression.

Mucins and their O-Glycans from human bronchial epithelial cell cultures.

A longstanding question in obstructive airway disease is whether observed changes in mucin composition and/or posttranslational glycosylation are due to genetic or to environmental factors. We tested whether the mucins secreted by second-passage primary human bronchial epithelial cell cultures derived from noncystic fibrosis (CF) or CF patients have intrinsically different specific mucin compositions, and whether these mucins are glycosylated differently. Both CF and non-CF cultures produced MUC5B, predominantly, as judged by quantitative agarose gel Western blots with mucin-specific antibodies: MUC5B was present at approximately 10-fold higher levels than MUC5AC, consistent with our previous mRNA studies (Bernacki SH, Nelson AL, Abdullah L, Sheehan JK, Harris A, William DC, and Randell SH. Am J Respir Cell Mol Biol 20: 595-604, 1999). O-linked oligosaccharides released from purified non-CF and CF mucins and studied by HPLC mass spectrometry had highly variable glycan structures, and there were no observable differences between the two groups. Hence, there were no differences in either the specific mucins or their O-glycans that correlated with the CF phenotype under the noninfected/noninflammatory conditions of cell culture. We conclude that the differences observed in the mucins sampled directly from patients are most likely due to environmental factors relating to infection and/or inflammation.

Role of nebulized antibiotics for the treatment of respiratory infections.

The purpose of this review is to summarize modern data pertaining to the use of aerosolized antimicrobials for the treatment of and prophylaxis against pulmonary infections. Few recent publications have examined the safety and efficacy of nebulized antibiotics. Two well conducted trials have been published that describe the utility of tobramycin solution for inhalation among cystic fibrosis patients. A couple of good reviews have also been published that have summarized the use of aerosolized antibiotics in other patient populations. Data regarding this topic are scarce. At this time, data support the use of aerosolized tobramycin solution for inhalation in cystic fibrosis patients infected or colonized by Pseudomonas aeruginosa. Apart from this situation, widespread aerosolized administration of other agents in cystic fibrosis and non-cystic fibrosis patient populations should not be advocated.

High genetic diversity among Stenotrophomonas maltophilia strains despite their originating at a single hospital.

The levels of genetic relatedness of 139 Stenotrophomonas maltophilia strains recovered from 105 hospitalized non-cystic fibrosis patients (51% from medical wards, 35% from intensive care units, and 14% from surgical wards) and 7 environmental sources in the same hospital setting during a 4-year period were typed by the pulsed-field gel electrophoresis (PFGE) technique. A total of 99 well-defined distinct XbaI PFGE patterns were identified (Simpson's discrimination index, 0.996). The dendrogram showed a Dice similarity coefficient ranging from 28 to 80%. Two major clusters (I and II), three minor clusters (III, IV, and V), and two independent branches were observed when using a 36% Dice coefficient, indicating a high diversity of genetic relatedness. It is of note that 84% of strains were grouped within two major clonal lineages. No special cluster gathering was found among strains belonging to the same sample type specimen, patients' infection or colonization status, and ward of precedence. Despite this fact, three different clones (A, B, and C) recovered from respiratory samples from six, three, and two patients, respectively, and two clones, D and E, in two bacteremic patients each, were identified. Isolation of an S. maltophilia strain belonging to the clone A profile in a bronchoscope demonstrated a common source from this clone. This study revealed a high genetic diversity of S. maltophilia isolates despite their origin from a single hospital, which may be related to the wide environmental distribution of this pathogen. However, few clones could be transmitted among different patients, yielding outbreak situations.

Evaluation of restriction fragment length polymorphism analysis of 16S rDNA as a tool for genomovar characterisation within the Burkholderia cepacia complex

A total of 154 Burkholderia cepacia complex strains, isolated from cystic fibrosis and non-cystic fibrosis patients and the environment, representing all nine genomovars and a putative tenth, were analysed by 16S rDNA-restriction fragment length polymorphism using the restriction enzymes AluI, CfoI and DdeI. Examining this diverse strain collection resulted in very diverse restriction patterns. Only B. cepacia genomovar VI could be identified unambiguously. The same restriction patterns were observed for B. cepacia genomovars I and III and approximately half of the Burkholderia ambifaria, B. anthina and B. pyrrocinia strains. Burkholderia vietnamiensis and B. ubonensis, a putative tenth B. cepacia complex genomovar, shared identical restriction profiles. The majority of Burkholderia multivorans and B. stabilis isolates generated a unique restriction pattern, but two strains of each showed divergent restriction profiles which were also observed in other genomovars.

Burkholderia cepacia complex in cystic fibrosis and non-cystic fibrosis patients: identification of a cluster of epidemic lineages

This study was performed in order to compare Burkholderia cepacia complex strains from cystic fibrosis (CF) and non-CF patients at the genomovar, genetic and epidemiological levels. A total of 92 B. cepacia respiratory tract isolates were obtained from patients attending the following CF centres: Catania and Palermo, Sicily; Gualdo Tadino, Central Italy, and Milan, Northern Italy. A total of 23 B. cepacia isolates were obtained from blood, surgical wound, and intravenous catheter sources of patients without CF, hospitalized in Catania and Varese, Northern Italy. Genomovar status identification, clonality and genetic relatedness determination, antibiotic susceptibility pattern determination and electron microscopy were performed. Transmission of infection was shown in both CF and non-CF patients by identifying clonality of responsible strains. In total 13 clones were involved in cross-transmission episodes. No outbreak was described involving both CF and non-CF patients. The present study indicates the existence of a distinct cluster of strains responsible for epidemics in CF and non-CF patients, based on their genetic relatedness, distinct from strains associated with no or negligible transmissibility. This result suggests that transmissibility is not only associated with a specific genomovar in CF patients, but also with a group of genetically related lineages in CF and non-CF patients. A key role is shown for both segregation measures and careful surveillance of infection, based on selective culture, molecular identification and epidemiological characterization of individual isolates.

Nasal potential difference measurements in patients with atypical cystic fibrosis.

The diagnosis of cystic fibrosis (CF) is based on characteristic clinical and laboratory findings. However, a subgroup of patients present with an atypical phenotype that comprises partial CF phenotype, borderline sweat tests and one or even no common cystic fibrosis transmembrane conductance regulator (CFTR) mutations. The aim of this study was to evaluate the role of nasal potential difference (PD) measurements in the diagnosis of CF patients with an atypical presentation and in a population of patients suspected to have CF. Nasal PD was measured in 162 patients from four different groups: patients with classical CF (n = 31), atypical phenotype (n = 11), controls (n = 50), and patients with questionable CF (n = 70). The parameter, or combination of nasal PD parameters was calculated in order to best discriminate all CF patients (including atypical CF) from the non-CF group. The patients with atypical CF disease had intermediate values of PD measurements between the CF and non-CF groups. The best discriminate model that assigned all atypical CF patients as CF used: e(response to chloride-free and isoproterenol/response to amiloride) with a cut-off >0.70 to predict a CF diagnosis. When this model was applied to the group of 70 patients with questionable CF, 24 patients had abnormal PD similar to the atypical CF group. These patients had higher levels of sweat chloride concentration and increased rate of CFTR mutations. Nasal potential difference is useful in diagnosis of patients with atypical cystic fibrosis. Taking into account both the sodium and chloride transport elements of the potential difference allows for better differentiation between atypical cystic fibrosis and noncystic fibrosis patients. This calculation may assist in the diagnostic work-up of patients whose diagnosis is questionable.

Burkholderia cepacia: current clinical issues, environmental controversies and ethical dilemmas.

Burkholderia cepacia is a plant phytogen and is known as a hardy and versatile organism. Over the past two decades it has emerged as a pathogen in the cystic fibrosis (CF) community, with devastating effects. Pulmonary colonisation can lead to an accelerated decline in lung function. In some cases, it causes a rapid and progressive pneumonic illness termed "cepacia syndrome", which is untreatable and fatal. B. cepacia is inherently resistant to multiple antibiotics and highly transmissible and virulent strains have been identified. CF patients colonised with the organism have to be segregated from their peers to try to prevent cross-infection. However, the pathogenicity of B. cepacia is not limited to CF. Other groups, such as individuals with chronic granulomatous disease and immunocompromised patients are vulnerable and it has caused disease in healthy individuals. However, the agricultural and petrochemical industries are attempting to exploit properties of B. cepacia for use as a biopesticide and biodegradation agent. This article provides an up to date review of clinically based literature on the Burkholderia cepacia complex, highlighting clinical management issues for both cystic fibrosis and non-cystic fibrosis patients. The article also addresses the potential conflict between medicine and agriculture on plans to reintroduce strains of Burkholderia cepacia back into the environment.

Distinct sputum cytokine profiles in cystic fibrosis and other chronic inflammatory airway disease

The dominant role of inflammation in airways disease progression in cystic fibrosis (CF) is now well established and, based on recent findings, the possibility of an inappropriate inflammatory response in the lung of patients with CF has emerged. In order to characterize this response, the aim of the present work was to evaluate the levels of a number of pro- and anti-inflammatory cytokines in the sputum of CF children and to compare these levels to those observed in the sputum from non-CF children with diffuse bronchiectasis (DB). Three groups of patients were investigated: a group of 25 CF children (mean age: 12.2 yrs), a group of 10 non-CF children with DB (mean age 11.5 yrs), and a group of five healthy young adults (mean age 24 yrs). Elevated concentrations of pro-inflammatory cytokines, tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-8 were found in children with CF and in non-CF children with DB, with significantly higher concentrations of IL-1beta in CF children. Analysis of the natural anti-inflammatory cytokine IL-1 receptor antagonist (IL-1ra) and type II TNF soluble receptor (sTNFRII) concentrations showed distinct patterns, with elevated levels of both inhibitors in CF patients, whereas only sTNFRII was found to be increased in non-CF children with DB. IL-10 data indicated low concentrations in the CF group. In all CF children, the concentrations of IL-6 in the airways were extremely low, independent of the clinical, bacteriological or functional status. By contrast, significantly increased IL-6 levels were found in non-CF children with DB. These results document distinct cytokine profiles in cystic fibrosis patients and noncystic fibrosis patients. They also suggest that impairment of interleukin-6 expression may represent an important component of the excessive inflammatory response observed in cystic fibrosis.

Distinct sputum cytokine profiles in cystic fibrosis and other chronic inflammatory airway disease.

The dominant role of inflammation in airways disease progression in cystic fibrosis (CF) is now well established and, based on recent findings, the possibility of an inappropriate inflammatory response in the lung of patients with CF has emerged. In order to characterize this response, the aim of the present work was to evaluate the levels of a number of pro- and anti-inflammatory cytokines in the sputum of CF children and to compare these levels to those observed in the sputum from non-CF children with diffuse bronchiectasis (DB). Three groups of patients were investigated: a group of 25 CF children (mean age: 12.2 yrs), a group of 10 non-CF children with DB (mean age 11.5 yrs), and a group of five healthy young adults (mean age 24 yrs). Elevated concentrations of pro-inflammatory cytokines, tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-8 were found in children with CF and in non-CF children with DB, with significantly higher concentrations of IL-1beta in CF children. Analysis of the natural anti-inflammatory cytokine IL-1 receptor antagonist (IL-1ra) and type II TNF soluble receptor (sTNFRII) concentrations showed distinct patterns, with elevated levels of both inhibitors in CF patients, whereas only sTNFRII was found to be increased in non-CF children with DB. IL-10 data indicated low concentrations in the CF group. In all CF children, the concentrations of IL-6 in the airways were extremely low, independent of the clinical, bacteriological or functional status. By contrast, significantly increased IL-6 levels were found in non-CF children with DB. These results document distinct cytokine profiles in cystic fibrosis patients and noncystic fibrosis patients. They also suggest that impairment of interleukin-6 expression may represent an important component of the excessive inflammatory response observed in cystic fibrosis.

Inhaled antibiotic therapy in non-cystic fibrosis patients with bronchiectasis and chronic bronchial infection by Pseudomonas aeruginosa

The aim of this study was to investigate the long-term effectiveness and safety of inhaled antibiotic treatment in non-cystic fibrosis patients with bronchiectasis and chronic infection by Pseudomonas aeruginosa, after standard endovenous and oral therapy for long-term control of the infection had failed. After completing a 2-week endovenous antibiotic treatment to stabilize respiratory status, 17 patients were randomly allocated to a 12-month treatment either with inhaled ceftazidime and tobramycin (group A) or a symptomatic treatment (group B). One patient from group A abandoned inhaled treatment because of bronchospasm and another from group B died before the end of the study. The remaining 15 patients, seven from group A and eight from group B, completed the study. Both groups had similar previous characteristics. The number of admissions and days of admission (mean ± sem) of group A [0·6 (1·5) and 13·1 (34·8)] were lower than those of group B [2·5 (2·1) and 57·9 (41·8)] ( P<0·05). Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV 1), P aO 2 and P aCO 2 were similar in the two groups at the end of follow-up, showing a comparable decline in these parameters. There were no significant differences either in the use of oral antibiotics or in the frequency of emergence of antibiotic-resistant bacteria between groups. Microbiological studies suggested that several patients had different Pseudomonas aeruginosa strains. None of the patients presented impaired renal or auditory function at the end of the study. This study suggests that long-term inhaled antibiotic therapy may be safe and lessen disease severity in non-cystic fibrosis patients with bronchiectasis and chronic bronchial infection by Pseudomonas aeruginosa which do not respond satisfactorily to antibiotics administered via other routes.

Abnormal expression of the cystic fibrosis transmembrane regulator in chronic sinusitis in cystic fibrosis and non-cystic fibrosis patients.

Cystic fibrosis (CF) patients commonly suffer from chronic sinusitis. Mutations of a single gene, the cystic fibrosis transmembrane conductance regulator (CFTR) gene, have been associated with CF. Functional CFTR protein is localized to the apical cell membrane, while dysfunctional CFTR is commonly found in the cytoplasm. We undertook a preliminary immunocytochemical study of CFTR subcellular localization in CF and non-CF pediatric and adult patients using a newly developed murine monoclonal antibody, TAM. Immunostaining was evaluated for subcellular localization (cytoplasmic versus membranous) and for epithelial layer (basal versus luminal). Analysis of the predominant CFTR distribution patterns demonstrated significant differences in adult versus pediatric groups independent of whether the latter were CF or non-CF (p<.0001 and p<.008, respectively), and no significant difference between the 2 pediatric groups (p = .70). This suggests that the pathophysiology of pediatric sinusitis differs from that of adult sinusitis at the level of secretion production.

Canadian Pseudomonas aeruginosa susceptibility study from 48 medical centers: focus on ciprofloxacin

We tested 1503 clinical isolates of Pseudomonas aeruginosa, from 48 Canadian medical centers, against ciprofloxacin and 11 other antimicrobial agents to determine in vitro activity. The frequency of susceptibility was highest for carbenicillin and ticarcillin (91% each) followed by imipenem and ceftazadime (90% each). Overall susceptibility (≤1.0 mg/l) to ciprofloxacin was 84% while resistance (≥4.0 mg/l) was 12%. Ciprofloxacin resistant isolates were more common from urinary tract specimens than from specimens collected from the respiratory and/or skin and soft tissue. Isolates from cystic fibrosis patients were more resistant to all agents tested than isolates from non-cystic fibrosis patients.

Single-dose and Steady-state Pharmacokinetics of a New Oral Suspension of Ciprofloxacin in Children

Quinolones are used ever increasingly in pediatrics, although officially they are still contraindicated. Lack of evidence of arthropathic effects in human offspring favors their use, but little is known about the pharmacokinetics of oral or parenteral ciprofloxacin in children, especially those without cystic fibrosis. We studied 16 non-cystic fibrosis patients ranging in age from 0.3 to 7.1 years to whom the new suspension formulation of ciprofloxacin (10 mg/kg body weight) was given orally three times daily. Single-dose and steady-state pharmacokinetic parameters were elucidated. Ciprofloxacin was rapidly absorbed. The maximum plasma concentrations, with the means varying from 1.7 to 3.6 mg/L, were reached within 1 hour, almost regardless of whether single-dose administration or steady state. The mean oral clearance was lower in children <6 years of age than in those >/=6 years. Terminal half-life values, with the means varying only between 4.2 and 5.1, suggest that dosing recommendations based on body weight are pertinent, although caution should be exercised in small infants. No arthropathic or other adverse events attributable to ciprofloxacin suspension were observed. A dose of the suspension form of ciprofloxacin of 10 mg/kg body weight given orally three times daily seems appropriate in children, provided the drug is clearly indicated.

Panel discussion: ciprofloxacin/quinolone use in non-cystic fibrosis patients

Panel discussion: ciprofloxacin/quinolone use in non-cystic fibrosis patients

Cytotoxicity of Pseudomonas aeruginosa internal lectin PA-I to respiratory epithelial cells in primary culture

Pseudomonas aeruginosa is the most important bacterial pathogen associated with chronic airway infection, especially in cystic fibrosis. We addressed the question of whether the galactophilic internal lectin of P. aeruginosa (PA-I) could represent a virulence factor for the respiratory epithelium. PA-I lectin was localized in all the bacteria of P. aeruginosa ATCC 33347 as determined by immunofluorescence staining. We investigated the dose-dependent effect of P. aeruginosa PA-I lectin on the growth, the ciliary beating frequency, and the morphology of human respiratory cells in primary culture of nasal polyps collected from non-cystic fibrosis patients. PA-I lectin significantly (P < 0.01) inhibited the growth of respiratory cells at a concentration of > or = 10 micrograms/ml. The percentage of active ciliated cell surface of the cultures decreased significantly (P < 0.05) at a PA-I lectin concentration of 50 micrograms/ml. Exposed to a low concentration of PA-I lectin (10 micrograms/ml), respiratory epithelial cells showed intracytoplasmic vacuoles when examined by light and transmission electron microscopy. At a higher concentration of PA-I lectin (100 micrograms/ml), major cell damage and severe epithelial shedding occurred. These results demonstrate that the P. aeruginosa internal PA-I lectin has a dose-dependent cytotoxic effect on respiratory epithelial cells in vitro. The P. aeruginosa PA-I lectin may represent a virulence factor by contributing to the respiratory epithelial damage during P. aeruginosa respiratory infections.

Pseudomonas aeruginosa: changes in antibiotic susceptibility, enzymatic activity, and antigenicity among colonial morphotypes.

Colonial variants of Pseudomonas aeruginosa have received renewed interest because of their occurrence in sputum cultures of patients with cystic fibrosis. We encountered 11 strains of P. aeruginosa from various body sites of non-cystic fibrosis patients. The strains showed two to three colonial variants, including smooth, rough, and iridescent morphotypes that arose from subculture of a single colony of P. aeruginosa originating from a primary source. The colonial segregants differed in antibiotic susceptibility (resistance to gentamicin, carbenicillin, chloramphenicol, and tetracycline), presence or absence of exoenzymes (gelatinase and elastase), degree of proteolytic activity (caseinase), pigmentation, and antigenicity. These observations suggest that in vivo dissociation with concomitant changes in enzymatic and surface properties might greatly enhance invasiveness. Concurrent differences in antimicrobial susceptibility among the colonial variants could account in some instances for the failure of antibiotic treatment in P. aeruginosa infections in which one would anticipate a positive therapeutic response.

The lung in cystic fibrosis: A quantitative study including prevalence of pathologic findings among different age groups

The autopsies of 82 patients with cystic fibrosis were reviewed with respect to pathologic changes in the lungs and their respective prevalence among different age groups. Although bronchitis, mucopurulent plugging, and bronchopneumonia were almost universally present among children of all ages, epithelial metaplasia and bronchiectasis were rarer among infants and progressively more prevalent in older age groups. Emphysema was absent in patients under two years of age and affected 11 per cent of the patients two to six years of age and 40 per cent of the patients older than six years, but was never of a severe degree by the point count method. Pulmonary hemorrhage, although uncommon, was usually associated with prominent arterial vessels in walls of bronchiectatic airways. Quantitative assessment of bronchial glands revealed Reid indices significantly higher in patients with cystic fibrosis when compared to noncystic fibrosis patients, but there was no increase in these indices with the age of the patients. Glandular hypertrophy, predominance of mucous acini within glands, and goblet cell hyperplasia of the bronchial mucosa all suggest an explanation for the copious mucous secretion of patients with cystic fibrosis. However, it was not possible to ascertain whether these findings reflect a general exocrine defect of such patients or whether they were merely a response to chronic airway infection, even though the latter is a more plausible assumption.