Dry barking cough in a child with and without fever: treatment

In pediatric practice, such a catarrhal symptom as a dry barking cough in a child is considered to be a result of irritation of the larynx (the upper part of the respiratory tube, where the vocal cords are located) and the trachea (through which inhaled air passes into the bronchi and lungs). A cough with a sharp, barking sound, without the release of tracheobronchial secretions, can occur both at normal and at elevated body temperatures.

Doctors recommend that parents in any case consult a doctor promptly, since in young children such a cough can be accompanied by laryngeal stenosis and suffocation.

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Epidemiology

The prevalence of false croup with a dry barking cough in different age groups is not the same: more than 50% of cases occur in two- to three-year-old children, slightly less often the disease develops in the first and fourth years of life. But after five years, the number of cases decreases sharply.

According to the Journal of Paediatrics and Child Health, acute laryngitis with airway stenosis accounts for more than 15% of cases of respiratory disease seen in pediatric practice, and the average age of patients is 18 months.

In the United States, the incidence rate is five cases per hundred children in their second year of life. Although most cases occur in late fall and winter, false croup can occur throughout the year. Boys are more likely to get it than girls.

According to the Canadian Medical Association, croup is diagnosed in more than 80,000 children each year (up to 5% are hospitalized), and is the second most common cause of respiratory distress in children aged six months to three years. The most common causative agent is the human parainfluenza virus (Respirovirus HPIV-1 and HPIV-3).

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Causes a dry, barking cough in a baby

The appearance of a sharp unproductive cough in children is caused by a number of reasons. The larynx may be irritated by too dry, dusty or polluted air; a foreign object may get into the trachea, which the child is trying to cough up.

But most often, the causes of a dry barking cough in a child are associated with an acute respiratory viral infection and inflammation of the laryngeal part of the pharynx and vocal folds (cords) - acute laryngitis (false croup) in children, which can also be called subglottic or obstructive laryngitis. The most typical form of false croup is acute stenosing laryngotracheitis, which causes obstruction of the airways in the larynx and trachea.

It is generally accepted that acute laryngotracheitis and spasmodic croup can develop only with viral infection, while the addition of a bacterial infection can cause further development of the disease, that is, its complications.

True (diphtheritic) croup cannot be ruled out – diphtheria of the pharynx in children with damage to the pharynx and larynx by the diphtheria bacillus (Corynebacterium diphtheriae). This infectious disease is accompanied by severe intoxication of the body and a dry barking cough with a temperature in the child up to +38.5 ° C, swelling of the pharynx and its obstruction by a fibrinous film. Now – thanks to vaccination against diphtheria – this disease is recorded extremely rarely, although, according to WHO data for 2016, Ukraine was among six countries in the world where less than 60% of the population was vaccinated.

Pediatricians note such a cough as the first signs of whooping cough; bacterial tracheitis; respiratory mycoplasmosis caused by Mycoplasma pneumoniae; pulmonary chlamydia (the causative agent is Chlamydia pneumoniae); developing respiratory allergies or bronchial asthma with wheezing and shortness of breath.

A cough like this may indicate the presence of a cyst or papilloma in the larynx, as well as an infestation with roundworms (Ascaris lumbricoides).

Less often, a dry barking cough without fever in a child occurs as a result of autoimmune pathologies, for example, with Wegener's granulomatosis.

Risk factors

Naming the key risk factors for the development of a dry barking cough in young children – in addition to weak general and humoral immunity, frequent respiratory diseases, perinatal damage to the central nervous system, prematurity, congenital anomalies of the larynx and predisposition to allergic reactions (atopic phenotype) – otolaryngologists and pulmonologists note the morphological immaturity of the upper respiratory tract in early childhood. In particular, the following anatomical and physiological features of the child's larynx and trachea predispose to the development of laryngitis and false croup:

• short narrow vestibule and funnel-shaped larynx;
• high-set and disproportionately short vocal folds;
• small diameter, softness and pliability of the cartilaginous skeleton;
• hyperexcitability of the adductor muscles that close the glottis.

Inflammation and swelling of the mucous membrane of the larynx and trachea (and sometimes the bronchi) caused by infection develop more quickly due to the weak development of elastic fibers in their submucosa, as well as the abundance of vessels and lymphoid tissue.

It is also necessary to take into account the characteristic for this age certain functional inadequacy of the reflexogenic zones of the respiratory system organs and increased parasympathicotonia - when the parasympathetic division of the autonomic nervous system is more active, providing innervation of the muscular and mucous tissues of the pharynx, larynx and lungs through the branches of the vagus nerve.

Children who are not vaccinated against whooping cough and diphtheria are at risk of becoming infected, and any child can catch roundworm: all it takes is dirty hands or eating poorly washed vegetables.

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Pathogenesis

In acute respiratory viral infections and false croup – acute laryngotracheitis in children of the first years of life – the pathogenesis of cough is caused by damage to the upper respiratory tract and trachea by influenza viruses, HRSV viruses, rhinovirus, coronavirus, Metapneumovirus HMPV and Adenoviridae, but in almost 70% of cases parainfluenza viruses are to blame (Respirovirus HPIV-1, HPIV-3 and Rubulavirus HPIV-2). Bacterial laryngitis (caused by group A streptococci, Moraxella catarrhalis or Haemophilus influenzae) is extremely rare.

As with most respiratory infections, the viral infection in acute laryngotracheitis begins in the nasopharynx and spreads to the larynx and trachea, where it develops because the portion of the trachea below the larynx is the narrowest part of the child's upper respiratory system. Diffuse inflammation, erythema, and swelling of the tracheal walls that limit the mobility of the vocal cords occur.

As a result, the classic symptoms of a dry barking cough in a child with chest pain, wheezing (inspiratory stridor) and hoarseness appear. Fever and rhinitis, cyanosis of the skin around the mouth, and retraction of the chest wall (intercostal retraction) may be observed. A dry barking cough at night in a child is also typical, since all the symptoms of croup most often worsen at night and can quickly change depending on how excited or calm the child is. Often, their severity depends on this - from moderate to severe (with a decrease in the lumen of the lower respiratory tract). Croup is a life-threatening disease.

In spasmodic croup, the swelling of the submucosal tissues of the trachea is non-inflammatory, and it is assumed that its pathogenesis is most likely allergic in nature. That is, the production of specific antibodies (IgE) to viral antigens provokes the release of histamine in the trachea, causing swelling and narrowing of its lumen.

In whooping cough, the mucous membrane of the respiratory tract is affected by the whooping cough bacillus (Bordetella pertussis), which secretes several types of toxins that irritate the receptors of the mucous epithelium and lead to an increase in the cough reflex.

In the case of ascariasis, irritation of the respiratory tract and coughing occur due to the migration of the larvae of this helminth from the intestines to the respiratory tract (with the bloodstream).

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Complications and consequences

The reactive inflammatory response in acute laryngotracheitis and spasmodic croup causes such consequences and complications as pharyngeal edema, airway obstruction, and the development of progressive hypoxia. This condition can be life-threatening for infants and children under three years of age. In Western countries, the mortality rate due to respiratory arrest does not exceed one case per 30,000 affected children on average.

Further extension of acute laryngitis from the trachea into the bronchi and alveoli of the lungs results in laryngotracheobronchitis and bronchopneumonitis, respectively. However, progressive obstructive disease at this level is usually the result of secondary bacterial infection.

Whooping cough can also lead to the development of inflammation of the lower respiratory tract - bronchitis, bronchiolitis, pneumonia and bronchopneumonia. In addition, severe coughing can cause hernias, pulmonary hypertension, pulmonary atelectasis and even a violation of their innervation at the cerebral level. Acute heart failure and asphyxia in whooping cough are the cause of respiratory arrest and death in infants and children under one year of age (in 1-2% of cases). In such situations, endotracheal intubation or intensive care with artificial ventilation of the lungs should be performed.

A common consequence of an allergic dry cough is the development of chronic obstructive bronchitis and bronchial asthma.

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Diagnostics a dry, barking cough in a baby

Since a dry barking cough in a child is a symptom, it is necessary to diagnose the diseases in which it appears.

A physical examination of the child by a physician (listening to the breath, percussion of the lungs, examination of the pharynx and throat) in some cases reveals cough, hoarseness, runny nose, normal or slightly inflamed throat and slightly rapid breathing. The rate of progression and degree of respiratory distress may vary considerably, resulting in increasing severity of obstruction, significant respiratory rate, cyanosis and tachycardia. Croup is an emergency and is usually diagnosed based on clinical signs and their intensity using the Westley scale. Further investigations, such as blood tests and viral cultures, are usually unnecessary.

A biochemical blood test, an enzyme immunoassay of blood (for antibodies) and PCR, for eosinophils; a throat culture (including for diphtheria) and serological studies, a stool test for helminthiasis should be taken if the child's condition does not improve with standard treatment, and there is every reason to suspect whooping cough, bacterial tracheitis, pulmonary chlamydia, allergy or ascariasis.

Diagnostic imaging – anteroposterior and lateral radiographs of the upper airway – can help differentiate croup from other causes of stridor and respiratory distress, such as foreign body, epiglottitis, or retropharyngeal/parapharyngeal abscess, with up to 93% accuracy. Airway visualization with ultrasound or laryngoscopy may be necessary. More information in the article – Diagnosis of acute laryngitis

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Differential diagnosis

Differential diagnostics is also designed to identify congenital anomalies of the respiratory tract (laryngomalacia and tracheomalacia); hypoplasia of the folds of the larynx; laryngocele, papillomas, neoplasms or hemangiomas; mediastinal tumors, Riedel's thyroiditis, etc.

Treatment a dry, barking cough in a baby

Etiological treatment of dry barking cough in a child consists of eliminating the causes of this symptom.

In case of whooping cough, it is important to ensure high air humidity and minimize any external irritants so as not to provoke coughing fits. Children aged two to three years are prescribed physiotherapy treatment in the form of oxygen therapy, the introduction of antitoxic anti-pertussis gamma globulin, and in more severe cases - antibiotics (erythromycin group, macrolides, cephalosporins). Read more - Whooping cough treatment

How to relieve a dry barking cough in a child? Methods of treating acute inflammation of the trachea, as well as medications prescribed for this disease, are described in detail in the material - Tracheitis in a child

In acute stenosing laryngitis or false croup (requiring urgent hospitalization of the child in 5-15% of cases), oxygen therapy is effective, as well as nebulizer inhalations for dry barking cough in a child with glucocorticosteroids - Dexamethasone (Decadron), Pulmicort (Budesonide) or Fluticasone (Flixotide). If necessary, GCS can be used orally and parenterally. Epinephrine inhalations are also done - in severe cases; racemic adrenaline usually leads to a decrease in the severity of the condition within 10-20 minutes for about the next two hours. In case of airway obstruction and the development of progressive hypoxia, endotracheal intubation is performed - tracheal intubation. In critical situations - with laryngeal stenosis and asphyxia - intensive therapy is resorted to using artificial ventilation of the lungs.

Since false croup is usually a viral disease, antibiotics are not needed, and a Cochrane review of antibiotic use in acute laryngitis (2016) confirmed that antibacterial drugs do not bring any benefit. However, if a secondary bacterial infection is suspected, antibiotics are prescribed (Azithromycin, Vancomycin, Cefotaxime, etc.). In severe cases associated with influenza A or B, antiviral inhibitors of viral n-proteins can be used.

What cough medicines, with the help of which a dry cough becomes productive (with the discharge of sputum), what inhalations are recommended and how to correctly use folk treatment and herbal treatment, are covered in detail in the publications - Treatment of dry cough in a child and Barking cough in a child

And if the cough has an allergic etiology, then antihistamines (Suprastin, Tavegil, Fenistil, etc.) are prescribed to relieve swelling, as well as agents for expanding the bronchi (bronchodilators). For more details, see - Allergic cough in children

Ascaris is usually removed with Pirantel in the form of a suspension or syrup: the drug is taken once, and the dosage is calculated based on the child's weight - 10 ml per kilogram. Nausea and intestinal upset are possible side effects of this drug.

Prevention

To prevent diseases that cause unproductive barking cough in children, it is very important to carry out timely vaccinations against diphtheria and whooping cough (DPT), as well as to prevent children from becoming infected with viral infections during flu epidemics. It is also necessary to ensure that the child's body receives all the necessary vitamins and sufficient fluids; to observe hygiene rules and carry out hardening procedures.

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Forecast

With adequate therapy of acute stenosing laryngotracheitis or whooping cough, the prognosis is favorable.

Viral croup is usually a self-limiting condition with the peak of symptoms on the second day from the onset of the disease (in eight cases out of ten). As a rule, the cough weakens within two days, less often - within a week. However, consequences in the form of acute inflammation of the trachea (bacterial in nature), pneumonia and pulmonary edema are not excluded.

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