From the Guidelines
Cystic fibrosis is characterized by several key clinical features, including chronic respiratory disease, pancreatic insufficiency, and gastrointestinal manifestations, resulting from dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) protein, as described in the most recent study 1. The most prominent features of cystic fibrosis include:
- Chronic respiratory disease with recurrent pulmonary infections, particularly from Pseudomonas aeruginosa and Staphylococcus aureus
- Pancreatic insufficiency, which affects about 85% of patients, leading to malabsorption, steatorrhea, failure to thrive, and malnutrition, as noted in 1
- Gastrointestinal manifestations, such as meconium ileus in newborns, distal intestinal obstruction syndrome, and rectal prolapse
- Males often experience infertility due to congenital bilateral absence of the vas deferens
- Sweat gland dysfunction, which results in elevated sweat chloride levels (>60 mmol/L), serving as a diagnostic hallmark, as mentioned in 1 Other features of cystic fibrosis include:
- Chronic sinusitis
- Nasal polyps
- An increased risk of diabetes mellitus (cystic fibrosis-related diabetes) These manifestations occur because the defective CFTR protein disrupts chloride transport across epithelial cells, leading to thick, viscous secretions that obstruct ducts and airways throughout the body, as explained in 1. The disease typically presents in early childhood, but can occasionally be diagnosed in adolescence or adulthood with milder phenotypes, as stated in 1. It is essential to note that the median predicted survival for cystic fibrosis patients has improved significantly, from 38 years for those born in 2008 to 48.4 years for those born in 2019, according to data from the Cystic Fibrosis Foundation 2019 Patient Registry Annual Data Report, as mentioned in 1.
From the Research
Key Clinical Features of Cystic Fibrosis
- Cystic fibrosis (CF) is a life-limiting genetic condition that affects several organs in the body, with airway damage having the most profound impact on quality of life and survival 2
- The condition is characterized by recurrent respiratory infections, with Staphylococcus aureus and Pseudomonas aeruginosa being common causes of lower airway infection 2
- Patients with CF often experience a decline in lung function, with forced expiratory volume (FEV1) being a key indicator of respiratory function 2, 3
- Clinical features of CF may include symptoms such as cough, fever, and pleural effusion, as well as a decrease in FEV1 3
- Co-infections with other bacterial species, such as Nocardia, are common in patients with CF, and may require antibiotic treatment 3
Treatment and Management
- Azithromycin is a commonly used antibiotic in the treatment of CF, with microbiological, immunomodulatory, and anti-inflammatory properties 4, 5
- Azithromycin maintenance therapy has been shown to improve respiratory function in patients with CF, although the optimal dose and duration of treatment are still debated 2, 5
- Treatment with azithromycin may be indicated in patients showing lung involvement, such as pneumonia or pleural effusion, or in patients undergoing pulmonary transplantation 3
- The emergence of antibiotic resistance and the potential for adverse events are important considerations in the use of azithromycin in CF patients 4