Achromobacter xylosoxidans Cellular Pathology Is Correlated with Activation of a Type III Secretion System.

Achromobacter xylosoxidans is increasingly recognized as a colonizer of cystic fibrosis (CF) patients, but the role that A. xylosoxidans plays in pathology remains unknown. This knowledge gap is largely due to the lack of model systems available to study the toxic potential of this bacterium. Recently, a phospholipase A2 (PLA2) encoded by a majority of A. xylosoxidans genomes, termed AxoU, was identified. Here, we show that AxoU is a type III secretion system (T3SS) substrate that induces cytotoxicity to mammalian cells. A tissue culture model was developed showing that a subset of A. xylosoxidans isolates from CF patients induce cytotoxicity in macrophages, suggestive of a pathogenic or inflammatory role in the CF lung. In a toxic strain, cytotoxicity is correlated with transcriptional activation of axoU and T3SS genes, demonstrating that this model can be used as a tool to identify and track expression of virulence determinants produced by this poorly understood bacterium.

Decreased TGF-ß1 and VEGF Release in Cystic Fibrosis Platelets: Further Evidence for Platelet Defects in Cystic Fibrosis.

PURPOSE: Cystic fibrosis (CF) patients suffer from chronic lung inflammation. This inflammation may activate platelets. There are limited data on the role of platelet-secreted cytokines in CF. Platelet cytokines with inflammatory effects include vascular endothelial growth factor (VEGF) and transforming growth factor-ß1 (TGF-ß1). As levels of these cytokines are tenfold greater in serum than plasma due to platelet release, serum levels may be one index of platelet content, but a more specific index is release during the aggregation of isolated platelets. We postulated that altered release of these platelet cytokines occurs in CF. METHODS: We obtained sera and plasma from CF outpatients (n = 21) and from healthy controls (n = 20), measured VEGF and TGF-ß1, assessed for correlations with platelet number, analyzed cytokine release during platelet aggregation to collagen, and analyzed differences in maximal platelet aggregation. RESULTS: Platelet number and maximal aggregation levels were higher in CF. Plasma and serum levels of TGF-ß1 and VEGF were higher in CF, but these levels were similar after adjusting for platelet number (serum cytokines correlated with platelet count). The release of VEGF and TGF-ß1 during aggregation was decreased in CF platelets (by 52 and 29 %, respectively). CONCLUSION: Platelet release is not a source of the elevated blood proinflammatory cytokines TGF-ß1 and VEGF in CF, as platelets from CF patients actually release less of these cytokines. These data provide further evidence for platelet defects in CF.

Inhaled antibiotics: the new era of personalized medicine?

PURPOSE OF REVIEW: Treatment options for individuals with cystic fibrosis (CF) have improved survival significantly over the past two decades. One important treatment modality is inhaled antibiotics to treat chronic infection of the airways. This review includes those antibiotics that are currently in use, those that are in clinical trials. It also includes review of nonantibiotic antimicrobials, a growing area of investigation in CF. RECENT FINDINGS: There are currently three inhaled antibiotics that are approved for use in patients with cystic fibrosis: tobramycin, aztreonam, and colistimethate. Tobramycin and colistimethate now are available as solution and new dry powder formulations, which are helping the treatment burden which has increased in CF. New antibiotics are in trial, although recently two did not meet primary outcomes in large clinical trials. Of particular interest is the development of nonantibiotic antimicrobials, which may allow treatment of intrinsically antibiotic resistant organisms. SUMMARY: Inhaled antibiotics remain an important treatment option in cystic fibrosis due to chronic airway infection as a hallmark of the disease. Although there are now multiple options for treatment, improvements in this treatment class are needed to treat intrinsically resistant organisms. New formulation of antibiotics and nonantibiotic antimicrobials are being evaluated to add to our armamentarium.

Vitamin D status and variable responses to supplements depend in part on genetic factors in adults with cystic fibrosis.

Vitamin D sufficiency has been difficult to achieve consistently in patients with cystic fibrosis (CF), even with robust oral supplements. To assess vitamin D status and resistance to supplementation, we studied 80 adults using 25-hydroxyvitamin D (25OHD) determinations and whole genome sequencing to construct polygenic risk scores (PRS) that aggregate variants associated with vitamin D status. The results revealed that 30 % of patients were below the threshold of 30 ng/mL and thus should be regarded as insufficient despite normal vitamin E status, a reflection of adherence to fat soluble vitamin supplementation. The PRS values were significantly correlated with 25OHD concentrations, confirming our results in children with CF, and indicating that genetic factors play a role and have implications for therapy.

Anemia in cystic fibrosis: incidence, mechanisms, and association with pulmonary function and vitamin deficiency.

BACKGROUND: Anemia is associated with increased morbidity and mortality in many chronic diseases. Little is known about anemia in cystic fibrosis (CF). Because the majority of patients with CF die of lung disease, the objective of this study was to identify the frequency, severity, and mechanisms of anemia in CF and to determine if there was an association between anemia and poor lung function in these patients. Vitamin deficiency was used to assess the association of malabsorption and anemia. METHODS: Charts of 218 CF patients (ages >1 month to 61 years) were reviewed. Information extracted included medical history, complete blood counts, iron studies, pulmonary function tests, vitamin levels, serum creatinine levels, and medications. RESULTS: As patients aged, anemia increased from 12% in those < 16 to 58.3% > or = age 40. Anemic patients had poorer lung function than nonanemic patients. Mean forced expiratory volume (FEV(1)) and forced vital capacity (FVC) were 51.6% (SEM +/- 10.3) and 69.7% (SEM +/- 9.3) in anemic and 82.5% (SEM +/- 9.2) and 95% (SEM +/- 8.3) in nonanemic patients, respectively (P < .001). Of vitamin-deficient patients, 90% were anemic whereas only 59.5% of nonvitamin-deficient patients were anemic (P = .02). Complete iron studies were only available in 17 of 48 anemic patients and 11 were diagnosed with iron deficiency. CONCLUSIONS: Anemia in CF is associated with poor lung function and vitamin deficiency. Although anemia was often incompletely evaluated, iron deficiency was common. Recognition and complete evaluation of anemia might be important for continued improvement of care in CF.

Epithelial lining fluid solute concentrations in chronic obstructive lung disease patients and normal subjects.

The exhaled breath condensate (EBC) method represents a new, noninvasive way to detect inflammatory and metabolic markers in the fluid that covers the airways [epithelial lining fluid (ELF)]. However, respiratory droplets represent only a very small and variable fraction of the EBC, most (approximately 99.99%) of which is water vapor. Our objective was to show that ELF concentrations could be calculated from EBC values by using any of three dilutional indicators (urea, total cations, and conductivity) in nine normal and nine chronic obstructive lung disease (COPD) subjects. EBC concentrations of Na(+), K(+), Ca(2+), Mg(2+), total cations, urea, and conductivity varied over a 10-fold range among individuals, but concentrations of these constituents (except Ca(2+)) remained well correlated (r(2) = 0.44-0.83, P < 0.001). Dilution (D) of respiratory droplets in water vapor was calculated by dividing plasma concentrations of the dilutional indicators by EBC concentrations. Estimates of D were not significantly different among these indicators, and urea D averaged 10,800 +/- 2,100 (SE) in normal and 12,600 +/- 3,300 in COPD subjects. Although calculated Na(+) concentrations in the ELF were less than one-half those in plasma, and concentrations of K(+), Ca(2+), and Mg(2+) exceeded those in plasma, total cation concentrations in ELF were not significantly different from those in plasma, indicating that ELF is isotonic in both normal and COPD subjects. EBC amylase concentrations (measured with an ultrasensitive procedure) indicated that saliva represented <10% of the respiratory (ELF) droplets in all but three samples. Dilutional and salivary markers are essential for interpretation of EBC studies.

FNAB cytology of extra-cranial metastasis of glioblastoma multiforme may resemble a lung primary: a diagnostic pitfall.

BACKGROUND: As extra-cranial metastasis of glioblastoma multiforme (GBM) is rare, it may create a diagnostic dilemma especially during interpretation of fine needle aspiration biopsy (FNAB) cytology. CASE PRESENTATION: We present transbronchial FNAB findings in a 62-year-old smoker with lung mass clinically suspicious for a lung primary. The smears of transbronchial FNAB showed groups of cells with ill-defined cell margins and cytological features overlapping with poorly differentiated non-small cell carcinoma. The tumor cells demonstrated lack of immunoreactivity for cytokeratin, thyroid transcription factor-1, and usual neuroendocrine markers, synaptophysin and chromogranin in formalin-fixed cellblock sections. However, they were immunoreactive for the other neuroendocrine immunomarker, CD56, suggesting neural nature of the cells. Further scrutiny of clinical details revealed a history of GBM, 13 months status-post surgical excision with radiation therapy and systemic chemotherapy. The tumor recurred 7 months earlier and was debulked surgically and with intra-cranial chemotherapy. Additional evaluation of tumor cells for glial fibrillary acidic protein (GFAP) immunoreactivity with clinical details resulted in final interpretation of metastatic GBM. CONCLUSION: Lack of clinical history and immunophenotyping may lead to a diagnostic pitfall with possible misinterpretation of metastatic GBM as poorly differentiated non-small cell carcinoma of lung in a smoker.

Exhaled breath condensates: a potential novel technique for detecting aspiration.

There is an urgent need for diagnostic procedures that can detect aspiration of oral and gastrointestinal (GI) secretions into the respiratory tract. Current approaches are limited by poor sensitivity and specificity. These techniques include (1) adding indicators to feedings; (2) recovery of lipid-filled macrophages in respiratory secretions; (3) measurement of changes in the pH of the upper GI and respiratory tracts; (4) endoscopic visualization of reflux events; and (5) measurement of increased glucose concentrations in respiratory secretions. Ideally, specific markers from various sites in the oral and GI tracts might be discovered in respiratory secretions, but conventional bronchoalveolar lavage for sampling respiratory secretions is not practical and involves some risk. Noninvasive measurements of indicators in the exhaled breath condensates could be used to detect aspiration, but a number of theoretical and practical aspects of such studies must be considered before this approach can be applied to the problem of aspiration.

Restrictive lung disease is an independent predictor of exercise intolerance in the adult with congenital heart disease.

BACKGROUND/OBJECTIVES: Following repair of congenital heart disease (CHD), adult patients are at risk for reduced exercise capacity. Restrictive lung disease (RLD) may contribute to reduced exercise capacity in this population. The aim of this study was to determine the prevalence of RLD and its impact on exercise tolerance in the adult with CHD. METHODS: One hundred consecutive adult patients with CHD, who underwent routine cardiopulmonary exercise testing with spirometry, were evaluated. Clinical data were obtained by retrospective chart review. RESULTS: Patients from 10 major diagnostic groups were identified. The median age for the cohort was 31 years (range 18-63) and included 43 males and 57 females. Most patients, 79%, had at least one previous surgical procedure. Based on spirometry and flow/volume loops, 50 patients were classified as normal pulmonary function, 44 patients had patterns suggestive of RLD, 4 suggestive of mixed (obstructive and restrictive), and 2 indeterminate. Risk factors associated with RLD include history of multiple thoracotomies (odds ratio = 9.01, P =.05) and history of atrial arrhythmias (odd ratio = 4.25, P =.05). Overall, 56% of the patients had abnormal exercise capacity. Spirometry suggestive of RLD was a significant risk factor for decreased exercise capacity (odds ratio = 3.65, P =.03). Patients with spirometry suggesting RLD also had lower exercise duration (P =.004) and a higher New York Heart Association Functional Class (P =.02). History of previous surgery and decreased heart rate reserve were also significant risk factors for decreased exercise capacity. CONCLUSION: Abnormal spirometry suggestive of RLD is common in the adult with CHD and is a significant risk factor for decreased exercise tolerance in this population. Further studies are needed to evaluate the relationship between RLD and exercise intolerance and its relationship to mortality in the adult with CHD.

The effects of volatile salivary acids and bases on exhaled breath condensate pH.

RATIONALE: Recent studies have reported acidification of exhaled breath condensate (EBC) in inflammatory lung diseases. This phenomenon, designated "acidopnea," has been attributed to airway inflammation. OBJECTIVES: To determine whether salivary acids and bases can influence EBC pH in chronic obstructive pulmonary disease (COPD). METHODS: Measurements were made of pH, electrolytes, and volatile bases and acids in saliva and EBC equilibrated with air in 10 healthy subjects and 10 patients. RESULTS: The average EBC pH in COPD was reduced (normal, 7.24 +/- 0.24 SEM; range, 6.11-8.34; COPD, 6.67 +/- 0.18; range, 5.74-7.64; p = 0.079). EBCs were well buffered by NH(4)(+)/NH(3) and CO(2)/HCO(3)(-) in all but four patients, who had NH(4)(+) concentrations under 60 micromol/L, and acetate concentrations that approached or exceeded those of NH(4)(+). Saliva contained high concentrations of acetate (approximately 6,000 micromol/L) and NH(4)(+) (approximately 12,000 micromol/L). EBC acetate increased and EBC NH(4)(+) decreased when salivary pH was low, consistent with a salivary source for these volatile constituents. Nonvolatile acids did not play a significant role in determining pH of condensates because of extreme dilution of respiratory droplets by water vapor (approximately 1:12,000). Transfer of both acetic acid and NH(3) from the saliva to the EBC was in the gas phase rather than droplets. CONCLUSIONS: EBC acidification in COPD can be affected by the balance of volatile salivary acids and bases, suggesting that EBC pH may not be a reliable marker of airway acidification. Salivary acidification may play an important role in acidopnea.

Utility of exhaled breath condensates in chronic obstructive pulmonary disease: a critical review.

PURPOSE OF REVIEW: Evaluation of the utility of exhaled breath condensates in chronic obstructive pulmonary disease. RECENT FINDINGS: Exhaled breath condensates have recently been introduced as a simple, noninvasive method of sampling respiratory fluid in inflammatory lung disorders, including chronic obstructive pulmonary disease. Increases in condensate concentrations of at least 12 markers of inflammation have been reported in these disorders. Furthermore, condensate pH appears to be decreased in both chronic obstructive lung disease and bronchial asthma. This has been referred to as acidopnea and could reflect airway acidification by inflammatory cells. Although safer and more convenient than bronchoalveolar lavage, interpretation of condensate data is complicated by uncertainty regarding the source of condensate solutes and by variable dilution of respiratory droplets from condensed water vapor, which represents more than 99.9% of condensate volumes. This dilution can be estimated from the dilution of plasma constituents such as urea or electrolytes. Because the principal buffer in condensate is NH4, much of which is derived from bacterial degradation of urea in the mouth, condensate pH measurements may not provide accurate estimates of airway pH. Nevertheless, acidification of condensate may be indicative of gastroesophageal reflux, which frequently occurs in obstructive lung diseases and may contribute to cough and bronchospasm. SUMMARY: It is too early to tell how useful condensate studies will be to pulmonary investigators and clinicians. Realization of the enormous potential of this approach will require a thorough understanding of the manner in which these solutions are generated and how they should be analyzed.

The promise and perils of exhaled breath condensates.

The exhaled breath condensate (EBC) approach provides a convenient and noninvasive approach for sampling the pulmonary epithelial lining fluid (ELF). Increased EBC concentrations of more than a dozen inflammatory markers and hydrogen ions have been reported in lung diseases associated with inflammation. However, the usefulness of EBC is compromised by uncertainties concerning the sources of the EBC droplets and by the extreme and variable dilution of ELF droplets with condensed water vapor ( approximately 20,000-fold). Reported increases in EBC concentrations may reflect proportionate increases in the total volume rather than the concentration of ELF droplets in the collected samples. Conclusions regarding ELF concentrations can only be made if this dilution is estimated with a dilutional indicator (e.g., conductivity of lyophilized EBC). In normal EBC samples, pH is effectively set by oral contamination with NH(3), and EBC pH cannot provide reliable information regarding ELF pH in normal subjects. Acidification of EBC observed in asthma and other conditions may reflect acidification of ELF, decreases in NH(3) added to the EBC, and/or the presence of gastric droplets in the EBC.

A simple method for estimating respiratory solute dilution in exhaled breath condensates.

Exhaled breath condensates have been widely used to detect inflammatory mediators in the fluid that covers airway surfaces of patients with inflammatory lung disorders. This approach is much less invasive than bronchoalveolar lavage, but respiratory droplets are markedly diluted by large and variable amounts of water vapor. We estimated the dilution of respiratory droplets by comparing concentrations of nonvolatile, reference indicators (total nonvolatile cations, urea or conductivity) in 18 normal subjects with normal plasma concentrations by assuming similar concentrations in the respiratory fluid and plasma. The volatile cation, NH4+ (most of which is delivered as NH3 gas from the mouth), represented 93 +/- 3% (SEM) of the condensate cations. More than 99% of the NH4+ was removed by lyophilization, making it possible to use conductivity to estimate total nonvolatile ionic concentrations and facilitating analysis of urea. Conductivity was significantly correlated with electrolyte and urea concentrations. Estimates of dilution based on total cations, conductivity, and urea were not significantly different (cations: 20,472 +/- 2,516; conductivity: 21,019 +/- 2,427; and urea: 18,818 +/- 2,402). These observations suggest that the conductivity of lyophilized samples can be used as an inexpensive, simple, and reliable method for estimating dilution of nonvolatile, hydrophilic mediators in condensates.