Bronchiolitis
The content of the article:
- Forms of the disease
- Causes and risk factors
- Symptoms
- Diagnostics
- Treatment
- Potential consequences and complications
- Forecast
- Prevention
Bronchiolitis is an inflammatory disease that affects the final section of the respiratory tract (bronchioles), usually developing as a complication of a respiratory viral infection and proceeding with symptoms of respiratory failure. As a rule, children of the first years of life suffer from bronchiolitis. The highest incidence rate is observed in babies from 2 to 6 months. Acute bronchiolitis is diagnosed annually in about 4% of children in the first two years of life. In 2% of them, the disease is severe and in 1% it is fatal. A severe course of bronchiolitis is characteristic of premature babies or children with congenital malformations of the heart and lungs.
Bronchiolitis in adults is extremely rare and only against the background of a significant weakening of the functions of the immune system. For example, in HIV-infected patients or patients who have undergone heart, lung, bone marrow transplantation.
Bronchiolitis is an inflammation of the bronchioles
Forms of the disease
Taking into account the peculiarities of the course of the disease and pathomorphological changes occurring in the lungs, acute and obliterating bronchiolitis are distinguished.
Causes and risk factors
In children of the first year of life, in 80% of cases, the development of acute bronchiolitis is associated with the respiratory syncytial virus. Much less often, other viral agents act as a causative agent (coronavirus, enterovirus, influenza and parainfluenza viruses, rhinoviruses, adenoviruses). After two years, acute bronchiolitis in children is more often caused by rhinoviruses and enteroviruses. Among children of preschool and primary school age, rhinoviruses and mycoplasma are most often the causative agents of the disease. Often, the causative agents of acute bronchiolitis are herpes simplex viruses, mumps (mumps), chickenpox and measles, as well as chlamydia, cytomegalovirus.
Already by the end of the first day from the moment of infection, necrosis of the epithelium of alveocytes and bronchioles begins, inflammatory mediators are actively released, mucus secretion increases, lymphocytic infiltration develops, against the background of which edema of the submucosa occurs. Thus, in acute bronchiolitis, airway obstruction occurs due to the accumulation of mucus in the lumen of the bronchioles and edema of their walls, and not bronchial spasm.
In children of the first year of life, bronchiolitis in most cases develops as a result of the respiratory syncytial virus
The small diameter of the bronchi in children, combined with inflammatory changes, causes an increased resistance to air flow. At the same time, during exhalation, the resistance is greater than during inhalation. As a result, an increased filling of the affected areas of the lungs with air develops, that is, emphysema is formed.
If there is a complete obstruction of the bronchioles, air cannot enter them, and atelectasis develops.
Against the background of acute bronchiolitis, the respiratory and ventilation function of the lungs significantly suffers, which leads to hypoxemia, and in the case of a severe course of the disease, to hypercapnia. With timely initiation of treatment, an improvement in the condition is noted after 3-4 days, however, the obstruction phenomena persist much longer, sometimes up to 2-3 months.
In obliterating bronchiolitis, the inflammatory process affecting the bronchioles leads to irreversible changes in their walls (obliteration of the lumen, concentric narrowing). The course of the disease is chronic, with periods of remission and exacerbations. The following factors can lead to the development of obliterating bronchiolitis:
- infectious - influenza viruses, parainfluenza, cytomegalovirus, respiratory syncytial virus, adenovirus, mycoplasma, HIV, legionella, Klebsiella, Aspergillus fungi;
- inhalation - inhalation of gases irritating the respiratory tract (ammonia, chlorine, nitrogen dioxide, sulfur dioxide), inorganic and organic dust, acid vapors, cocaine, as well as smoking (including passive);
- medicinal - taking certain medications (cytostatics, gold preparations, amiodarone, sulfonamides, antibiotics of the penicillin and cephalosporin series);
- idiopathic - the disease develops against the background of systemic connective tissue diseases (systemic lupus erythematosus, rheumatoid arthritis), inflammatory processes in the digestive tract (Crohn's disease, ulcerative colitis), lymphoma, Stevens-Johnson syndrome, malignant histiocytosis, aspiration pneumonia, allergic exogenous alveolitis;
- post - transplant - obliterating bronchiolitis develops in 20-50% of patients who have undergone bone marrow, lung, heart transplantation.
Symptoms
Acute bronchiolitis begins with nasal congestion, an increase in body temperature to subfebrile values. After a few days, symptoms appear indicating damage to the lower respiratory tract:
- shortness of breath with shortness of breath (expiratory type);
- dry obsessive cough;
- wheezing.
At the same time, the patient's general condition worsens, the temperature rises to 39-40 ° C.
Stages of bronchiolitis
Against the background of acute bronchiolitis, children develop tachycardia, tachypnea. In the process of breathing, auxiliary muscles begin to participate. Perioral cyanosis develops, which, with an increase in respiratory failure, is replaced by cyanosis of all skin integuments. The increasing emphysema of the lungs leads to a flattening of the dome of the diaphragm, as a result of which the liver and spleen begin to protrude from under the edge of the costal arch.
Symptoms of bronchiolitis obliterans at the time of exacerbation are similar to those of the acute form of the disease. Without exacerbation, the condition of patients improves, signs of respiratory failure are weakening. In the terminal stage of the disease, constant "puffing" breathing and persistent cyanosis are noted.
Diagnostics
Diagnosis of acute bronchiolitis is carried out on the basis of the characteristic clinical picture of the disease, data from physical examination, laboratory and instrumental examination. On auscultation, a “wet lung” is heard (multiple crepitating and fine bubbling rales). With percussion, the box shade of the percussion sound is determined, which is explained by emphysema of the lungs.
Listening with a phonendoscope refers to the initial stage of diagnosing bronchiolitis
Be sure to conduct a study of the gas composition of the blood, which allows you to evaluate the parameters of oxygenation. An x-ray of the lungs is performed to confirm the diagnosis.
Bronchiolitis requires differential diagnosis with the following diseases:
- cystic fibrosis;
- pneumonia;
- foreign body of the respiratory tract;
- chronic obstructive pulmonary disease;
- bronchial asthma.
Treatment
The development of acute bronchiolitis in children is an indication for hospitalization. The child is either placed in an oxygen tent or supplied with humidified oxygen through a face mask. With an increase in respiratory failure, there may be indications for tracheal intubation and transfer of the patient to mechanical ventilation. To replenish fluid losses, the child is often given warm drinks in small portions. If you refuse to drink independently, the required volume of fluid is injected intravenously. To facilitate the discharge of mucus, vibration massage of the chest, salt inhalations are performed. In case of an extremely severe course of bronchiolitis, especially in children of the first half of life, inhalations of Ribamidil (Ribavirin) may be prescribed.
In acute bronchiolitis, the child should be supplied with oxygen through a face mask or placed in an oxygen tent.
With bronchiolitis in adults, glucocorticoids can be used in a short course (they are ineffective in children). Antibiotics for bronchiolitis are prescribed only in case of a secondary bacterial infection.
Potential consequences and complications
Acute bronchiolitis is often accompanied by the following complications:
- bronchial hyperreactivity;
- respiratory failure;
- bacterial pneumonia;
- respiratory distress syndrome;
- myocarditis;
- otitis media;
- extrasystole.
Forecast
With timely treatment of acute bronchiolitis, patients usually recover within 7-10 days. The mortality rate does not exceed 1%. In children with bronchopulmonary dysplasia and congenital heart defects, the disease often takes a protracted course.
The prognosis for obliterating bronchiolitis is unfavorable. The disease progresses rapidly and is accompanied by increasing cardiopulmonary failure.
Prevention
Prevention of bronchiolitis includes:
- isolation of children and adults with ARVI;
- compliance with the rules of personal hygiene;
- influenza vaccination;
- proper nutrition;
- hardening.
Elena Minkina Doctor anesthesiologist-resuscitator About the author
Education: graduated from the Tashkent State Medical Institute, specializing in general medicine in 1991. Repeatedly passed refresher courses.
Work experience: anesthesiologist-resuscitator of the city maternity complex, resuscitator of the hemodialysis department.
The information is generalized and provided for informational purposes only. At the first sign of illness, see your doctor. Self-medication is hazardous to health!
