A new study by researchers at Tianjin Medical University in China offers more insight into the features of bronchiolitis obliterans in children under long-term azithromycin treatment. The study was published in the journal Experimental and Therapeutic Medicine and is entitled “Clinical features of post-infectious bronchiolitis obliterates in children undergoing long-term azithromycin treatment.”
Bronchiolitis obliterans is a rare, life-threatening obstructive lung disorder characterized by inflammation and fibrosis (scar tissue) of the small airways due to damage or injury of the respiratory bronchioles. The condition leads to a narrowing or full obstruction of the airways. The diagnosis of bronchiolitis obliterans is based on several factors, namely the insult to the lower respiratory tract (usually an infection), computed tomographic (CT) findings, poor exercise tolerance and persistent symptoms (like coughing and wheezing) non-responsive to bronchodilator therapy. However, the disorder is often undiagnosed or misdiagnosed as other pediatric lung diseases, which may aggravate the clinical outcome.
Azithromycin is an antibiotic widely used in the treatment of certain bacterial infections, including respiratory ones. It has been reported to be an effective therapy for long-term use in patients with conditions like asthma and mycobacterial diseases.
The goal of the study was to describe the clinical and radiological characteristics of post-infectious bronchiolitis obliterans (PIBO) and treatment options in pediatric patients. The long-term effect of azithromycin treatment in these patients was also assessed.
The team retrospectively analyzed data on 16 cases of children with PIBO. Researchers found that the most common infectious agents involved were adenovirus and Mycoplasma pneumoniae. Patients experienced persistent shortness of breath (dyspnea), wheezing, chronic cough and sputum production after the initial lung infection. Chest X-rays showed pulmonary over-inflation and patchy ground-glass opacity; while high-resolution computed tomography (HRCT) scans confirmed the patchy ground-glass opacity and revealed bronchial wall thickening and bronchiectasis, a respiratory condition characterized by a chronic inflammation that leads to irreversible airway dilatation and scarring. These features were observed in all 16 patients.
All children received treatment with low-dose azithromycin and prednisone (a corticosteroid with immunosuppressive properties). Follow-up visits between 7 and 31 months after the start of the treatment revealed that 10 of the patients had an improved disease condition.
According to the authors, since PIBO is a rare disorder, there are a limited number of reports and trials regarding treatment strategies, thus, therapeutic decisions are often empirically based. Treatment is often made through oral or inhaled corticosteroids.
The team emphasizes that PIBO patients should be treated by a multidisciplinary team and receive follow-up examination for an extended period. They suggest that oral azithromycin should be considered a therapeutic option for these patients given the fact that long-term therapy contributes to an improvement in patient’s condition. The team believes that patchy ground-glass opacity features on HRCT scans indicate BO, especially in children with persistent and severe wheezing, and that it is a feature that can be used to assess disease development.