bubble_chart Overview

Acute bronchitis often occurs secondary to upper respiratory tract infections and is a common complication of certain acute infectious diseases such as measles, whooping cough, influenza, diphtheria, etc. It may also be an early manifestation of pneumonia.

bubble_chart Etiology

Any viruses or bacteria that can cause upper respiratory infections can also lead to bronchitis. However, most cases result from secondary bacterial infections following a viral infection. Therefore, mixed viral and bacterial infections are quite common. The more common pathogenic bacteria include pneumococcus, hemolytic streptococcus, staphylococcus, and Haemophilus influenzae.

bubble_chart Clinical Manifestations

1. Symptoms may have an acute or insidious onset, with fever and cough being the main manifestations. The fever pattern is variable but is mostly low-grade. Infants, young children, or debilitated children may develop high fever. Initially, the cough is irritative and dry, but as secretions increase, it becomes productive with audible phlegm, transitioning from mucoid to mucopurulent. In infants and young children, coughing often worsens in the morning or during excitement, occasionally presenting with paroxysmal whooping cough-like episodes. Other symptoms may include lethargy, tachypnea, vomiting, and diarrhea. Older children may experience headache, chest pain, general malaise, and fatigue.
2. Signs vary depending on the stage of the disease. Pharyngeal congestion and slightly increased respiratory rate may be observed. On lung auscultation, breath sounds are coarse, and sometimes a few dry rales or coarse moist rales can be heard. A characteristic feature of these rales is their variability—they often decrease or even disappear after changes in posture or coughing.

Additionally, in infancy, there is a special type of bronchitis known as asthmatic (or wheezing) bronchitis. Its etiology may involve bronchospasm triggered by an allergic response to infection. It is more common in overweight children under 2 years of age with a history of eczema or other allergies. Apart from the general symptoms of bronchitis mentioned above, these children also exhibit asthma-like symptoms. On auscultation, wheezing is predominant, though moist rales may also be heard, and percussion yields a tympanic note. This condition has a tendency to recur and often progresses to bronchopneumonia due to secondary bacterial infections. Most cases resolve spontaneously by school age, but a few may develop into bronchial asthma.

bubble_chart Auxiliary Examination

Chest X-rays often show no abnormal changes or may reveal increased hilar shadows and thickened lung markings. In cases of acute bronchitis caused by viruses, the total white blood cell count in peripheral blood is usually normal or slightly elevated. When caused by bacteria or complicated by bacterial infection, both the total white blood cell count and neutrophil count are increased.

bubble_chart Treatment Measures

Generally the same as upper respiratory tract infection. Additionally, use

1. to control infection as appropriate: for children with bacterial infections, broad-spectrum antibiotics can be selected.
2. Dispelling phlegm: For mild cough, avoid administering antitussives to prevent suppression of natural expectoration. For severe cough with thick sputum, nebulization or steam inhalation can be used, or options such as 10% ammonium chloride, ipecac syrup, and Chinese medicinals like Panting-Arresting Decoction or Belamcanda and Ephedra Decoction may be considered.
3. Relieving asthma: For those with asthma symptoms, oral aminophylline can be given. For cases accompanied by dysphoria or restlessness, diphenhydramine or sedatives may be combined. For severe asthmatic bronchitis, oral prednisone or hydrocortisone (or dexamethasone) added to a 10% glucose solution for intravenous drip can be administered.
4. Bronchitis vaccine: For recurrent cases, it can prevent relapse. Begin injections when not in an active episode, once daily. The initial dose is 0.1ml, increasing by 0.1ml each time if no adverse reactions occur, up to a maximum of 0.5ml per dose. A course consists of 10 injections. For those with significant effects, multiple courses may be continued.

bubble_chart Differentiation

Severe bronchitis is difficult to distinguish from early bronchiolitis or pneumonia. In such cases, they should all be treated as pneumonia.