Antimicrobial Treatment of Staphylococcus aureus in Patients With Cystic Fibrosis.

Staphylococcus aureus is a ubiquitous human commensal pathogen. It is commonly isolated in cystic fibrosis (CF) patients and is considered one of the main causes of the recurrent acute pulmonary infections and progressive decline in lung function that characterize this inherited life-threatening multisystem disorder. However, the true role of S. aureus in CF patients is not completely understood. The main aim of this narrative review is to discuss the present knowledge of the role of S. aureus in CF patients. Literature review showed that despite the fact that the availability and use of drugs effective against S. aureus have coincided with a significant improvement in the prognosis of lung disease in CF patients, clearly evidencing the importance of S. aureus therapy, how to use old and new drugs to obtain the maximal effectiveness has not been precisely defined. The most important problem remains that the high frequency with which S. aureus is carried in healthy subjects prevents the differentiation of simple colonization from infection. Moreover, although experts recommend antibiotic administration in CF patients with symptoms and in those with persistent detection of S. aureus, the best antibiotic approach has not been defined. All these problems are complicated by the evidence that the most effective antibiotic against methicillin-resistant S. aureus (MRSA) cannot be used in patients with CF with the same schedules used in patients without CF. Further studies are needed to solve these problems and to assure CF patients the highest level of care.

A Peculiar Case of Pneumonia due to Mycoplasma pneumoniae in a Child with Cystic Fibrosis and Sensibilization to Aspergillus fumigatus.

Aspergillus fumigatus plays a major role in pulmonary exacerbations in patients with cystic fibrosis. The most common A. fumigatus diseases are those based on immune-mediated response to A. fumigatus antigens; including allergic bronchopulmonary aspergillosis (ABPA). In this condition; the presence of A. fumigatus in the lower respiratory tract triggers an IgE-mediated hypersensitivity response that causes airway inflammation; bronchospasms; and bronchiectasis. This case report describes a ten-year-old male patient suffering from cystic fibrosis (CF) in whom the diagnosis of ABPA occurred in association with pneumonia due to Mycoplasma pneumoniae more than two weeks after hospitalization. This case is a good example of how difficult the identification of ABPA in CF patients can be and highlights that ABPA can occur in association with co-infections due to other pathogens. In order to avoid the risk of a late ABPA diagnosis, it is imperative that the diagnostic criteria guidelines are reviewed and standardized.

A Clinical and Molecular Survey of 62 Cystic Fibrosis Patients from Umbria (Central Italy) Disclosing a High Frequency (2.4%) of the 2184insA Allele: Implications for Screening.

Genetic testing strategies and counseling in cystic fibrosis (CF) can be problematic due to its extreme allelic heterogeneity and the difficult clinical interpretation of rare variants. Since in a previous survey of Italian CF patients, Umbria (a small region with about 900,000 inhabitants) was excluded due to the low number of chromosomes tested (<50), we have performed a comprehensive retrospective clinical and molecular survey of 62 CF patients coming from this region. We have summarized all the genotypic and phenotypic data in a table, and we interviewed the older patients in order to obtain a comprehensive overview of their conditions. We found that the c.2052_2053insA (2184insA) variant, a class I mutation with high frequency in Eastern Europe but very rare in Italy, is the fourth most frequent allele in Umbria. The 2184insA variant was not included in the first-level regional screening, and we therefore suggest the implementation of this variant in the future.