Chapter 2. Respiratory diseases

2.1. Acute bronchitis

Formulating a diagnosis

Components of the diagnosis: etiological variant (approximate or verified); the nature of bronchial mucosa inflammation; localization of inflammation; clinical form; phase of the disease

Acute bronchitis (AB) is a self-limiting respiratory disorder caused by acute, polyetiological inflammation of bronchial tree mucosa, manifested predominantly by cough with or without sputum production that lasts up to 3 weeks, and systemic signs and symptoms.

Etiological variant

Acute bronchitis is a polyetiological disease and can be caused by both infectious and non-infectious factors.

Viral infection is the primary cause of most episodes of acute bronchitis. A wide variety of viruses have been shown to cause acute bronchitis, including influenza, rhinovirus, adenovirus, coronavirus, rotavirus, parainfluenza, and respiratory syncytial virus. Table 2.1 presents the main etiological factors.

Table 2.1. Etiological types of acute bronchitis

The main etiology of the disease is viral, it accounts for 90–95% of all cases and only 5–10% for other factors, including bacterial ones. The most common is mycoplasmal and chlamydial bronchitis. However, it should be noted that both vaccinated and those who suffered from pertussis, due to immunity weakening, may get sick again with a mild course with bronchitis pattern.

In the absence of obvious reasons, AB is considered not otherwise specified.

The nature of bronchial mucosa inflammation

• Catarrhal (superficial inflammation).
• Edematous (with edema of bronchial mucosa).
• Purulent (purulent inflammation).

Localization of inflammation

Acute bronchitis is divided into proximal (damage to large bronchi) and distal (damage to small bronchi) by localization. Bronchiole damage is con­sidered a separate, independent disease — acute bronchiolitis.

Clinical form

• AB with no bronchial obstruction.
• AB with bronchial obstruction.

Bronchial obstruction is mainly observed in patients with distal localization of acute bronchitis, developed as a result of an acute inflammatory process leading to bronchospasm, edema and sputum accumulation in bronchi.

Phase (course) of the disease

• Acute (2–3 weeks).
• Protracted (1 month or more).

No functional classification of acute bronchitis taking into account se­verity of the disease has been developed due to the fact that uncomplicated acute bronchitis usually proceeds stereotypically and does not require differen­tiation by severity. In presence of bronchial obstruction, its severity is assessed depending on the severity of functional disorders:

• mild — 60% <FEV₁ <80%;
• moderate — 30% <FEV₁ <60%;
• severe — FEV₁ <30%.

Examples of diagnoses

DS: Acute catarrhal bronchitis, presumably of viral etiology, distal loca­lization, with moderate bronchial obstruction, protracted course.

DS: Acute catarrhal bronchitis, presumably of mycoplasmic etiology, pro­ximal localization.

DS: Acute not otherwise specified bronchitis, proximal, with moderate bronchial obstruction.

Diagnosis verification

Acute bronchitis is a clinical diagnosis based on the patient’s complaints, past medical history, epidemiological situation, lung exam, and other physical findings. Acute bronchitis is often characterized by a “descending” infection that develops in combination with tracheitis and simultaneously with an acute respiratory disease or immediately after it, or after exposure to chemical or physical factors that violate the mechanisms of natural respiratory tract pro­tection and lead to initial non-infectious inflammation. With infectious etio­logy, incubation period lasts from two to five days.

Quick tips

The diagnosis of acute bronchitis is established in a patient with sudden onset of cough that lasts no more than 3 weeks, with or without sputum expectoration, and without evidence of other causes (pneumonia, common cold, acute asthma, or an acute exacerbation of chronic bronchitis).

In acute bronchitis pattern of viral etiology, two main symptom complexes can be distinguished: systemic signs and symptoms and respiratory. The clinical presentation is characterized by the features of the AB virus that caused it.

Patient complaints

Acute bronchitis can present with fever, constitutional symptoms, and a productive cough.

In the acute phase, the patient’s complaints are associated with systemic signs and symptoms: fatigue, “ache” in the body, pain in the leg muscles is possible, increased sweating, or chills, subfebrile or febrile body temperature, sometimes with tracheobronchitis, body temperature may remain normal. Rough, sonorous, often “barking” and paroxysmal cough is typical, which in the first 2–3 days is often non-productive or is accompanied by the discharge of an insignificant amount of thick sputum. During this period, cough is often accompanied by pain and “soreness” in the throat and behind the sternum, hoarseness. On day 2–3, the cough becomes productive with the discharge of mucoid or mucopurulent sputum. Sometimes, the cough may remain non-productive throughout the disease. Some patients with bronchial obstruction occurrence may experience a feeling of stuffiness in the chest and dyspnea that significantly increases with physical exertion.