Generality
Bronchiolitis in infants is an infectious disease that involves the lower airways . The pathology is characterized, in particular, by damage to the very small bronchial branches (called bronchioles ) that border on the lung tissue (ie with the alveoli in the lungs).
The pathological process underlying bronchiolitis in newborns causes inflammation with edema, increased mucus production, and necrosis of bronchial epithelial cells. All this leads to a considerable reduction of the bronchial lumen, which in the small child is already, as a rule, very restricted.
Initially, the inflammation and swelling of the bronchioles caused by the infection induce symptoms similar to those of the common cold : stuffy nose or rhinorrhea, cough and fever. In the 2-3 days following the onset of these first manifestations, bronchiolitis in newborns gets worse and causes the appearance of a growing difficulty in breathing, with shortness of breath, breathlessness and tachypnea.
The infection at the origin of the inflammation is usually viral. In most cases, the responsible causative agent is respiratory syncytial virus (RSV), which mainly affects children under one year of age. Less frequently, bronchiolitis in newborns is due to influenza viruses (A and B), parainfluenza (1, 2 and 3) and adenovirus.
The diagnosis is suspected starting with the history and can be confirmed by a rapid virological test, performed on a swab or nasal wash. Most often, bronchiolitis resolves spontaneously and without consequences, however, in some cases, hospitalization may be necessary, especially under 3-6 months of life .
Bronchiolitis therapy in newborns is supportive and generally involves the administration of oxygen, rest, hydration and intravenous nutrition.
What is Bronchiolitis
Bronchiolitis in newborns is an acute viral infection that triggers an inflammatory process of the thinnest branches of the respiratory tree (bronchioles). The result is hypersecretion of mucus and thickening of the bronchi which can make breathing difficult.
Bronchiolitis mainly affects children younger than two years, with greater prevalence in the first 6 months of life .
Causes
Bronchiolitis in newborns is caused by an acute lower respiratory infection .
In most cases, the pathogenic agent implicated in the pathological process is respiratory syncytial virus (RSV) . This microorganism is responsible for various respiratory infections during early childhood and causes small epidemics, especially in winter. In fact, contracting the infection is very simple: as in the case of the flu or the common cold, it is sufficient to breathe contaminated droplets emitted into the air by coughing, sneezing or talking, or touching contaminated objects (eg toys) and then carelessly passing hands over eyes, mouth or nose.
The respiratory syncytial virus causes an intense inflammation of the bronchiole and the exfoliation of the epithelial cells inside it.
Respiratory syncytial virus: notes
The respiratory syncytial virus is a viral agent capable of infecting the respiratory system of patients of any age. In the tissues in culture infected with this pathogen, the cells merge together giving rise to a conglomerate (syncytium), from which the name derives.
In adults and older children, infection with respiratory syncytial virus causes a sort of cold, while in children under two years it can cause dyspnea, even very severe, due to the small size of the respiratory tract.
Other possible aetiological agents of bronchiolitis in newborns include:
- Influenza viruses (A and B);
- Parainfluenza viruses 1, 2 and 3;
- Adenovirus.
Less frequently, bronchiolitis in newborns is a consequence of the infection with:
- Rhinovirus;
- Retrovirus;
- Measles virus;
- Mycoplasma pneumoniae.
Often, bronchiolitis in newborns occurs in an epidemic form. Most cases occur in the autumn and winter months, especially between November and April, with a peak incidence between January and February.
Mode of infection
The transmission of bronchiolitis in newborns can occur by air or by direct contact with infected oropharyngeal secretions. The incubation period is short, ranging between 2 and 5 days.
Risk factors
In pediatric age, getting bronchiolitis is easier due to the immaturity of both the immune system and the lungs.
To make the infection more likely, other risk factors also participate, such as:
- Prematurity (to be born before the 37 weeks of gestation);
- Congenital cardiac or pulmonary disorders;
- Family predisposition for allergies and asthma;
- immunosuppression;
- Living in crowded conditions or coming into contact with other children, who could be carriers of the virus.
In newborns, other important risk conditions for developing a severe form of bronchiolitis are:
- Never been breastfed;
- Being exposed to cigarette smoke;
Bronchiolitis mainly affects children under the age of 24 months, with a peak incidence in infants born less than 6 months .
To know
Usually, the symptoms of bronchiolitis in children over two years of age and in adults are mild and resolve easily. If there are no complications, the healing phase usually occurs within a week, even if the difficulty in breathing, especially if severe, may require therapy for longer periods of time. When the disease strikes newborns, however, very severe problems may arise, such as difficulty in feeding, and in the most severe cases hospitalization is necessary.
Symptoms and Complications
The onset of bronchiolitis in newborns is typically acute.
After about 2 days in which the symptoms of a common cold, with little cough, rhinorrhea (runny nose) and modest fever (rarely above 38 ° C) occur, there is a difficulty in breathing (dyspnea) progressively increasing which precipitates the child's condition.
Within a few hours, the breath becomes labored and accelerated (tachypnea) and appears:
- Tachycardia;
- Pallor or cyanosis (the child presents the skin, especially of the face and around the lips, of bluish color);
- Lack of appetite (reduction of nutrition compared to usual);
- Dehydration (the diapers are dry for 12 hours);
- An insistent and irritating cough;
- Other signs of breathing difficulties:
- Hisses, crackling rattles and other breathing noises;
- Short recurrent apnea crises;
- Prolonged exhalation;
- Retractions at the height of the jugulum (base of the neck), intercostal and epigastric (a sign that the newborn suffers from increased efforts in breathing);
- Irritability and crying;
- Insomnia.
In these conditions, the newborn affected by bronchiolitis tends to be dehydrated, both due to respiratory distress and the consequent greater water loss, and to the simultaneous difficulty in taking breast milk or bottle feeding. Often, a hypoxaemic state is present, that is a lower oxygenation of the blood, which manifests itself clinically with a bluish color ( cyanosis ) around the mouth and at the extremities.
As the infection progresses, patient children may become increasingly lethargic . Infants with bronchiolitis can become so tired that they have difficulty maintaining their breath; if the latter becomes more superficial and ineffective, it can induce respiratory acidosis.
In many infants with bronchiolitis, concomitant acute otitis media is present.
Possible consequences
The possible complications of bronchiolitis in newborns may include:
- Respiratory diseases, including asthma, in old age;
- Acute respiratory failure;
- Secondary infections, such as pneumonia.
Healing times
If medical care is adequate, bronchiolitis in newborns is related to an excellent prognosis: most children recover in 3-5 days without consequences, despite the wheezing and coughing can last for a few weeks. The manifestations associated with the disease will gradually improve, and usually there are no long-term problems.
Only in some patients does respiratory failure develop which makes the course more prolonged.
Diagnosis
The diagnosis of bronchiolitis in newborns is established on the basis of:
- Anamnesis: before starting the visit of the newborn, the pediatrician takes care of the collection of data and information that can be useful to formulate the final diagnosis (eg season of the year or appearance of the disease during a known epidemic, age of the child, presence of the infection in other members of the family and persons in their contact, etc.);
- Physical examination : the presence of some characteristic signs of the clinical picture are confirmed by the doctor, who auscultates the newborn's lungs with a stethoscope.
The infectious agent primarily responsible for bronchiolitis in newborns - that is, the respiratory syncytial virus - can be identified with a molecular diagnostic test to search for genetic material, such as RT-PCR (reverse transcription PCR), or the detection of viral antigens on mucus aspirate, swab or nasal cavity wash.
In some cases, other tests may be necessary, such as blood tests and chest x-rays, to ascertain or exclude the presence of complications (such as thickening of atelectasis and thickening of the bronchial mucosa).
In young children, symptoms similar to bronchiolitis are caused by asthma and gastro-oesophageal reflux with inhalation of gastric contents. The differential diagnosis must also be placed against pertussis and cystic fibrosis.
When to consult a doctor
It is advisable to call the pediatrician if the newborn with bronchiolitis manifests:
- Breathing difficulties;
- Feed reduction (feeds halved compared to usual);
- Absence of urine for at least 12 hours;
- High fever or altered states (excessive irritability or fatigue).
The parent must immediately contact 118 or go to the emergency room, when the child:
- Become lethargic (excessive sleepiness, tiredness and no response to external stimuli);
- It presents serious respiratory difficulties or rather long apnea;
- It has a bluish skin, especially on the face and around the lips;
- He suddenly feels cold.
Treatment and Remedies
Most often, bronchiolitis in newborns resolves spontaneously and without consequences, however, in some cases, hospitalization may be necessary, especially under 3-6 months of life.
To alleviate the symptoms, especially in the initial stages, supportive therapy provides adequate hydration combined with rest and nasal washes with physiological water to free the nose of the baby from excess mucus. The doctor could also prescribe the use of bronchodilators to improve respiratory function.
Not being effective against viral infections, the use of antibiotics is foreseen only in the event that bacterial complications have occurred.
When contracted in the first 6 months of life, bronchiolitis can make hospitalization necessary, to monitor the evolution of the disease and manage any problems, for example, with the administration of oxygen and injecting nutrition . Medicines mainly used in hospitals can include asthma and / or cortisone drugs.
In infants with particularly severe bronchiolitis, antivirals are an additional option; this approach reduces the severity and duration of the disease but, to be effective, it must be started at the earliest stage.
Useful tips
- Following the instructions of the pediatrician and the right care, the newborn can recover from bronchiolitis, without consequences. The resolution of the pathology requires a period ranging from one week to one month (most newborns recover in 3-5 days, despite the wheezing and coughing can last for 2 weeks).
- To promote the fluidization of the mucus and prevent dehydration, it is good to breastfeed or give much drink to the newborn (both breast milk and artificial milk are suitable for this purpose): small, but more frequent meals can help achieve this goal.
- The newborn with bronchiolitis should be kept as vertical as possible, perhaps seated, in order to facilitate breathing. For the same reason, it is useful to adequately humidify the environments in which they stay and not expose the child to passive smoking.
- Pay attention to any worsening of breathing difficulties: in case of severe wheezing, apneas or cyanosis, it is best to take the newborn to the emergency room.
