Bioelectrical impedance in young patients with cystic fibrosis: Validation of a specific equation and clinical relevance.

BACKGROUND: Body composition (BC) analysis based on bioelectrical impedance analysis (BIA) provides conflicting results. The purpose of the study was to validate an equation specific for young patients with cystic fibrosis (CF), describe their BC and investigate its association with lung function. METHODS: Fifty-four young CF patients were evaluated by BIA and dual X-ray absorptiometry (DXA). An empirically derived CF-specific equation for fat-free mass (FFM) estimation by BIA was elaborated after stepwise multivariate regression and the agreement between BIA and DXA was assessed by Bland-Altman plots. The association between BC and lung function was investigated by regression analysis. RESULTS: The mean difference between the BIA and DXA assessment was close to zero. A total of 22.5% of patients (n=9) presented a FFM z-score≤-2. They had a worse pulmonary function and diaphragmatic impairment. Among these 9 patients, 7 had a normal BMI z-score>-1. CONCLUSIONS: BIA, based on a CF-specific equation, is a reliable method for BC assessment and allows the identification of patients at risk of nutritional degradation and bad respiratory prognosis.

Vaccine coverage in CF children: A French multicenter study.

BACKGROUNDS: Recent reports have pointed the low vaccine coverage in patients with chronic diseases. Data are lacking in patients with cystic fibrosis (CF). Gaining more information on coverage both for mandatory vaccines and those more specifically recommended would help to optimize care of these patients. METHODS: Data were extracted from the "MucoFlu" study, which was a prospective study performed in 2009 in the 5 cystic fibrosis centers of the Paris metropolitan area. Data on mandatory and recommended vaccines in CF were collected in the health booklet and compared to the coverage of the general population. RESULTS: A total of 134 CF children were included. Vaccination coverage for mandatory vaccines was insufficient (DTPCaHi, conjugate pneumococcal, BCG, MMR and hepatitis B) at 1year of age with no catching-up with age in contrast to the general population. Approximately 66% of the children had immunization for seasonal influenza and 91% for 2009 pandemic flu. Coverage for vaccines specifically recommended in CF was low for hepatitis A, non conjugate pneumococcal and varicella. CONCLUSION: This study shows a defect in vaccine coverage for both routine immunization and vaccines more specifically recommended in CF.

Factors associated with humoral immune response to pandemic A/H1N1(v) 2009 influenza vaccine in cystic fibrosis.

Influenza vaccination is recommended in cystic fibrosis patients. The objective of this study was to assess the immunogenicity of vaccination against 2009 pandemic A/H1N1 influenza and to study the factors associated with the immune response in patients with cystic fibrosis. 122 patients with cystic fibrosis were enrolled in a prospective study and received 1 dose of 2009/H1N1v adjuvanted vaccine, or for children <2 years and lung-transplanted patients, two doses of non-adjuvanted 2009/H1N1v vaccine administered 21 days apart. Hemagglutination inhibition antibodies were assessed before and 21 days after vaccination and at least 6 months after vaccination. After vaccination, 85% of the patients had an influenza antibody titer ≥1:40 and 69% seroconverted. 13% of the transplanted patients seroconverted compared with 72% of the non-transplanted patients. In this latter group, non-adjuvanted vaccine and low body mass index were independently associated with lower response to vaccination. 86% of the non-transplanted patients with normal BMI and receiving adjuvanted vaccine seroconverted. Persistence of seroprotection 10 months after vaccination was found in 50% of the patients. In patients with cystic fibrosis, malnutrition and receipt of non-adjuvanted vaccine were associated with lower immune response to pandemic influenza vaccination. Our data also suggest a potential defect in the immune response to influenza vaccination of patients with cystic fibrosis and raise the question of whether a different immunization strategy is needed.

[Inhaled treatments in cystic fibrosis: what's new in 2013?]. / Mucoviscidose et traitements inhalés: quoi de neuf en 2013?

In the past few years some new inhaled drugs and inhalation devices have been proposed for the treatment of cystic fibrosis. Breath-controlled nebulizers allow increased pulmonary deposition, with a lower variability and a shorter delivery time. The new dry powder formulations of tobramycin, colistine and mannitol require a change in the inhalation technique which must be slow and deep. In the field of the inhaled mucolytic drugs, hypertonic saline and mannitol have an indication in some patients. With regard to antibiotics, dry-powder tobramycin and colistine can be substituted for the same drug delivered by nebulization. Nebulized aztreonam needs more studies to determine its place. These new treatments represent a definite advance for cystic fibrosis patients and need to be known by all practitioners. Their position in our therapeutic arsenal remains to be accurately defined.

[Anti Pseudomonas aeruginosa antibiotic therapy in cystic fibrosis (exclusion of macrolides)]. / Stratégie antibiotique contre Pseudomonas aeruginosa dans la mucoviscidose (macrolides exclus).

Antibiotherapy is one of the main treatment in cystic fibrosis. Pseudomonas aeruginosa infection is one of the main causes of pulmonary degradation. The chronic sputum colonisation is characterized by the emergence of the mucoid phenotype, the formation of biofilm and the induction of excessive inflammatory response and consecutive tissue lesion. The choice of antibiotics depends on quantitative and qualitative analysis of sputum, bacteria resistance phenotypes and severity of infection. Treatment of P. aeruginosa is different in case of first colonization or chronic infection. In the first case, parenteral antibiotherapy (beta-lactams-aminoglycosids) followed by inhaled antibiotherapy may eradicate the germ. In the other case, superinfections can be treated with parenteral biantibiothérapy (beta-lactams or quinolons and aminoglycosides) during 15 to 21 days. This is associated with a better nutritional and respiratory status and a prolonged survival. Inhaled antibiotics between the courses have decreased the number of superinfections. This prolonged antibiotherapy must be monitored because of possible induction of bacterial resistance, nephrotoxicity and ototoxicity of aminosids and allergy to beta-lactams.

The role of inflammation in childhood asthma.

The role of inflammation in adult asthma is well known, involving a cascade of immunological stimulation in which mast cells and eosinophils play pivotal roles. However, the assessment of airway inflammation in children is more difficult as the invasive methods used in adults cannot ethically be used for this purpose alone. Nevertheless, limited data from studies using invasive methodology, and studies using novel non-invasive techniques such as sputum induction and nitrous oxide exhalation, are improving knowledge. The immunopathology in childhood asthma appears to mirror that in adult sufferers. The inflammatory processes are evident at an early age in wheezing infants who later develop asthma, and there are different "wheezing phenotypes" in children with atopic asthma or viral associated wheeze. The mechanisms underlying childhood asthma are dependent not only on increased numbers of inflammatory cells in the airways, but also increased activation of these cells. In vitro data have shown that corticosteroids can inhibit the secretion of proinflammatory compounds from alveolar macrophages, suggesting a potential important role for these agents in halting the development of asthma. Techniques for measuring inflammation in infants need to be refined, in order to provide increased knowledge and accurate monitoring of the disease. It is hoped that this will enable the development of early interventions to minimise the impact of asthma in infants who are identified as being susceptible.

Cytokine transcripts in pediatric tuberculosis: a study with bronchoalveolar cells.

Pediatric tuberculosis (TB) differs from adult TB in many features. To date, cytokine expression has not been studied in children with TB. The relative amounts of the various cytokines released at the site of infection may be important determinants of TB disease development and pathology. We determined cytokine transcripts in bronchoalveolar cells (BACs) recovered from 9 children presenting with TB and from 9 children with pulmonary diseases other than TB. An RT-PCR-based method was developed to quantify the mRNAs encoding six cytokines (IFN- gamma, IL-12, TNF- alpha, IL-10, IL-4, TGF- beta 1) known to play key roles in mycobacterial infections. Expression of mRNA encoding TGF- beta, TNF- alpha and IFN- gamma was statistically significantly higher in BACs from children with TB than in BACs from children with other pulmonary diseases; whereas the levels of mRNA transcription for TGF- beta is high, the levels of mRNA transcription for IFN- gamma and TNF- alpha remain low. All children had low levels of mRNA for IL-12(p40). IL-4 was barely detectable in all cases. Children with miliary TB had high levels of IL-10 transcripts and low levels of mRNA encoding TGF- beta. The immunosuppressive cytokines TGF- beta and IL-10, are overproduced in children with non-miliary TB and miliary TB respectively and are probably involved in the progression of the disease. These data suggest that Th1 responses are reduced in children with TB.