Cystic fibrosis adult care: consensus conference report

Diabetes: a major co-morbidity of cystic fibrosis

Cystic fibrosis-related diabetes (CFRD) is a frequent complication of cystic fibrosis, its prevalence increases with age of patient and is close to 30% at the age of 30 years. As life expectancy greatly increases, the number of cystic fibrosis patients developing diabetes will increase too. CFRD shares some features with type 1 and type 2 diabetes, initial phase is characterised by postprandial hyperglycaemia followed by a progression toward insulin deficiency. Insulin deficiency is an essential factor in the development of diabetes with an additional contribution of insulin resistance. Systematic screening with an oral glucose tolerance test is recommended from the age of 14 years because clinical signs of CFRD are often confused with signs of pulmonary infection and CFRD occurrence is associated with weight and pulmonary function deterioration. In observational studies CFRD diagnosis is associated with a significant increase in mortality, while treatment allow correction of weight and lung deterioration suggesting that CFRD has a significant impact on CF evolution. Microvascular complications are recognised, although paucity of data does not permit a clear description of their natural history. Annual screening for microvascular complication is recommended. There is no evidence by now that CF patients develop macrovascular complications. The only recommended pharmacological treatment is insulin therapy.

Immunisation in the current management of cystic fibrosis patients

Although no special recommendations exist, clearly patients with cystic fibrosis (CF) can benefit from immunisation. We reviewed the literature regarding vaccination in CF and other chronic diseases. CF subjects should follow national immunisation programmes without delay to obtain optimal vaccination coverage. Indeed they may escape normal programmes due to frequent hospital admissions and school absenteeism and may be more at risk to get "vaccine-controlled" diseases at any age. There is no uniform European immunisation schedule for basic infant and childhood vaccines or for vaccines against hepatitis A (HAV) and B (HBV), varicella (VZ) and booster vaccinations. HAV and HBV vaccination is appropriate in CF as recommended in general for patients with chronic liver disease (CLD). Varicella (VZ) vaccination is not recommended in all European countries. There are no recent data about possible worsening of pulmonary status following VZ in CF, but it is known to cause pulmonary damage in non-CF adults and to be potentially fatal post transplantation and during steroid treatment. Therefore it is recommended at least for seronegative adolescents and transplant candidates. Influenza vaccine is recommended annually for CF patients aged > or =6 months. Pneumococcal vaccine is generally indicated for CF patients. RSV infection might play a role in the initial Pseudomonas colonization and the decline in pulmonary function. However no RSV vaccine is available at present. There are no recommendations for palivizumab in CF as an alternative but expensive prophylaxis. Anti-bacterial vaccinations protecting directly against Pseudomonas aeruginosa colonisation are promising for the future, potential candidates are currently being assessed in phase III clinical trials. More studies are needed to complete recommendations especially for CF adults and transplant candidates.

Failure of high-dose ergocalciferol to correct vitamin D deficiency in adults with cystic fibrosis

RATIONALE

Treatment guidelines for vitamin D monitoring and supplementation in cystic fibrosis (CF) have recently been developed and published by a consensus committee, but have not been prospectively tested.

OBJECTIVES

To use these guidelines to determine the percentage of adults with CF requiring vitamin D repletion therapy and to evaluate the effectiveness of the currently recommended high-dose oral ergocalciferol repletion protocol.

METHODS

Prospective study of clinical outcomes after therapy with the recommended vitamin D repletion algorithm.

RESULTS

Of 134 adults with CF, 109 (81.3%) were found to have 25-hydroxyvitamin D (25-OHD) levels below the recommended 30 ng/ml. Sixty-six of these adults completed the recommended course of 400,000 IU of oral ergocalciferol over 2 months, and only five (8%) responded with correction of their serum 25-OHD to the goal of 30 ng/ml or greater (mean change, +0.3 ng/ml; from 18.8 to 19.1 ng/ml). In the 33 adults with CF who also completed the recommended second course of 800,000 IU of ergocalciferol over 2 months, none demonstrated correction of their deficiency (mean change, -1.2 ng/ml).

CONCLUSION

The results of this study demonstrate that a majority of adults with CF have serum 25-OHD levels below 30 ng/ml, and the currently recommended ergocalciferol repletion regimen often does not fully correct vitamin D deficiency and may need to be revised to include even higher dosing of ergocalciferol. Further work is needed to establish the ideal 25-OHD level for maximizing calcium absorption and bone health in CF.

Cystic fibrosis prenatal screening in genetic counseling practice: recommendations of the National Society of Genetic Counselors

For over a decade, prenatal screening for cystic fibrosis (CF) has been considered a model for the integration of genetic testing into routine medical practice. Data from pilot studies and public policy discourse have led to recommendations by some professional organizations that CF screening should be offered or made available to pregnant women and their partners, and to couples planning a pregnancy. It is crucial that genetic counselors gain thorough understanding of the complexities of CF and the implications of positive test results, so that they may serve as a reliable, educated referral base and resource for health care providers and their patients. While not all pregnant women will be referred for genetic counseling prior to CF carrier testing, genetic counselors often will be asked to counsel clients after they have a positive test result, or who are found to be at increased risk. Genetic counselors can play an important role in providing accurate and current information as well as support for patients' informed decisions. These recommendations were created by a multicenter working group of genetic counselors with expertise in CF and are based on personal clinical experience, review of pertinent English language medical articles, and reports of expert committees. The recommendations should not be construed as dictating an exclusive course of management, nor does the use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a particular client.

[Etiological work-up for bronchectasia in adults]

Search for an etiology of bronchiectasis consists in identifying constitutional or acquired defense mechanisms of the respiratory mucosa. The question is timely because causes change. In developing countries, presumed sequelae of infection account for about 30% of the cases despite vaccination campaigns, control of endemic tuberculosis, and widespread use of antibiotics. Genetic diseases account for 20% of the causes when identified by high-performance prospective diagnostic tests (CFTR mutation). Computed tomography enables the identification of frequent associations between bronchiectasis and rheumatoid disease or ulcerative colitis. Recent diseases such as HIV infection or GVHD can also lead to bronchiectasis. Nevertheless, the cause remains unknown in 30-50% of patients. After a detailed analysis of the clinical presentation and diagnostic criteria specific for each etiology, we propose a two-phase diagnostic procedure. The first step, used for all patients (careful history taking, physical examination, imaging, bronchofibroscopy, limited blood tests) enables detecting localized bronchial obstacles and obvious etiologies (situs inversus of primary ciliary dyskinesia, known systemic disease, HIV...). If the first step is negative, the second phase is oriented by the clinical context. Sequelae of infection (tuberculosis...) in older subjects or migrants, a genetic cause in younger subjects, particularly if there is a familial history and/or infertility, a systemic disease or allergic bronchopulmonary aspergillosis if there is an extra-respiratory context. This etiological search should help improve patient management and provide a better prognosis and prevention of bronchiectasis.