Cystic fibrosis (CF)

Definition

Cystic lung fibrosis is a clinical variant of systemic cystic fibrosis with predominant damage to mucus-producing glands of the respiratory tract. Pulmonary fibrosis is characterized by an attack-like cough with viscous sputum, choking attacks, dyspnea, and recurrent bronchopneumonia. As the pathology progresses, patients form respiratory failure and pulmonary heart. Radiologic and endoscopic studies and spirometry are performed to assess lung changes in cystic fibrosis. Treatment of pulmonary fibrosis is symptomatic: mucolytics, inhalation, physiotherapy, massage, sanation, and bronchoscopy.

General information

Pulmonary fibrosis is a respiratory form of cystic fibrosis characterized by hyperproduction of sputum, development of bronchial obstructive syndrome, chronic bronchopulmonary infections, and secondary changes (bronchiectasis, pulmonary emphysema, pneumosclerosis, cardiopulmonary insufficiency). Cystic fibrosis is a hereditary pathology and occurs in about 1-4 per 10,000 newborns. The disease can occur in four clinical variants: intestinal, pulmonary, mixed (pulmonary-intestinal), and in the form of meconium ileus in newborns. The pure pulmonary form of cystic fibrosis occurs in about 15-20% of patients, but some degree of lung damage in cystic fibrosis occurs in 95% of observations. On this basis, cystic fibrosis is an interdisciplinary medical problem at the intersection of genetics, pediatrics, pulmonology, and gastroenterology.

Symptoms of pulmonary fibrosis

Signs of respiratory cystic fibrosis usually become apparent as early as infancy. A history of meconium ileus in the newborn period makes it easier to recognize cystic fibrosis in children.

Typical clinical manifestations of pulmonary fibrosis are hypersecretion of bronchial mucus, obstructive syndrome, and secondary infection. An early sign is an excruciating cough that occurs in fits and resembles whooping cough. Cough paroxysms may be accompanied by vomiting and attacks of suffocation. Sputum is expectorated with great difficulty and has a viscous, mucous, or mucopurulent character.

In older age, complaints of dyspnea at minor exertion or at rest are typical. In the medical records of children with pulmonary fibrosis, one can find indications of frequent exacerbations of chronic purulent or obstructive bronchitis, recurrent pneumonia (including abscessed pneumonia), maxillary sinusitis, nasal polyps, and bronchial asthma. Children with pulmonary fibrosis are hypotrophic, lagging in physical development, have to limit themselves in physical activity.

The skin is pale, and acrocyanosis is pronounced. The thorax acquires a barrel shape, and chronic respiratory failure transforms the distal phalanges of fingers and toenails. Secondary changes in the pulmonary system in pulmonary cystic fibrosis include bronchiectasis, emphysema, diffuse pneumosclerosis, and the pulmonary heart.

The course of the pulmonary form of cystic fibrosis has four stages. The first stage, lasting up to 10 years, is characterized by periodic dry cough and shortness of breath on exertion. At the second stage of pulmonary fibrosis, bronchial damage progresses, and the clinic of chronic bronchitis develops, with its characteristic wet cough and increased dyspnea. The course of this stage will vary from 2 to 15 years. Transition to the third stage marks the development of secondary changes: bronchiectasis, pneumofibrosis, respiratory and cardiac failure, the duration of this period – 3-5 years. In the fourth terminal stage of pulmonary fibrosis, decompensation of cardiopulmonary insufficiency with a fatal outcome occurs in a matter of months.

Diagnosis

Most cases of pulmonary fibrosis are detected as a result of neonatal screening for inherited metabolic diseases (phenylketonuria, cystic fibrosis, galactosemia, congenital hypothyroidism, and congenital adrenal hyperplasia). In cysticfibrosis, the concentration of immunoreactive trypsin in newborns’ cystic fibrosis blood is 5-10 times higher than in healthy children. Prenatal diagnosis of cystic fibrosis is performed by determining alkaline phosphatase isoenzymes in amniotic fluid after 18-20 weeks of pregnancy.

A recognized diagnostic standard is the so-called Gibson and Cooke sweat test (ionophoresis with pilocarpine), which allows the concentration of chloride and sodium ions in the sweat fluid to be determined (in cystic fibrosis, the level of chloride is increased 2 – 5 times).

Auscultatory findings in pulmonary fibrosis usually correspond to the picture of obstructive bronchitis. The degree of damage to the bronchopulmonary system can be assessed using radiologic and endoscopic imaging methods. Lung radiography reveals the strengthening of the pulmonary pattern and its heavy character, pulmonary atelectasis, increased transparency of the lung fields, restriction of mobility of the diaphragm dome, etc.

Diagnostic bronchoscopy in pulmonary fibrosis reveals a picture of diffuse purulent endobronchitis: the presence of thick, viscous secretion in the bronchial lumen, often in the form of purulent plugs. Bronchography reveals cylindrical or mixed bronchiectasis. Spirometry diagnoses obstructive-restrictive type disorders (decreased Tiffeneau index, FEV1, etc.); in late stages – decreased FVC.

Treatment of pulmonary fibrosis

Treating the pulmonary form of cystic fibrosis includes general regime measures and symptomatic therapy. Patients’ nutrition should be caloric and rich in multivitamins, trace elements, and protein. An integral part of treating a patient with pulmonary fibrosis becomes kinesitherapy: special breathing exercises, postural drainage, percussion, and vibration chest massage help free the bronchi from accumulating thick and viscous secretion.

Mucolytic therapy aims to liquefy sputum: inhalation, enzymes, hypertonic solution, corticosteroids, administration of acetylcysteine, ambroxol, and others. Bronchial lavage procedures with endobronchial administration of mucolytics are carried out. Codeine-containing drugs are categorically contraindicated in pulmonary fibrosis.

Antibiotic therapy is prescribed at the first signs of pulmonary infection. The choice of drug is based on the results of sputum culture and antibiogram; most often, aminoglycosides, cephalosporins, azithromycin, clarithromycin, and others are used. Physical therapy is used to relieve exacerbation. In terminal stages, patients with cystic fibrosis may undergo lung transplantation or heart-lung complex.

All these treatment options are available in more than 80 hospitals worldwide (https://doctor.global/results/diseases/cystic-fibrosis-cf). For example, lung transplantation can be performed in 9 clinics across Germany (https://doctor.global/results/europe/germany/all-cities/all-specializations/procedures/lung-transplantation). 

Prognosis

Patients with pulmonary fibrosis need lifelong observation, first by a pediatrician and a pediatric pulmonologist, then by a general practitioner and an adult pulmonologist, adherence to the recommended diet and lifestyle, and special courses of treatment. The prognosis of pulmonary fibrosis remains unfavorable despite significant advances in early diagnosis and therapy of the disease. Currently, the average life expectancy of patients is about 30 years. Spouses who have cystic fibrosis patients in their family should consult a geneticist to predict the probability of having a child with pathology.