From the Guidelines
Asymmetrical apical thickening on a chest x-ray is indicative of a potential pulmonary or pleural abnormality, which may be suggestive of conditions such as tuberculosis, histoplasmosis, or malignancy.
Key Considerations
- In patients with a history of tuberculosis, asymmetrical apical thickening may be consistent with post-primary tuberculosis, and treatment with isoniazid 300mg daily and rifampicin 600mg daily for a duration of 6 months may be considered 1.
- Alternatively, in patients with a history of asbestos exposure, asymmetrical apical thickening may be consistent with benign asbestos-related disease, and serial imaging with chest x-rays at 6-12 month intervals may be recommended for monitoring 2, 3.
Diagnostic Approach
- High-resolution computed tomography (HRCT) may be used to further evaluate the extent of pleural thickening and to distinguish it from other conditions such as emphysema or bronchiectasis 4.
- The International Classification of Radiographs of Pneumoconiosis (ILO classification) may be used to classify the radiographic severity of pneumoconiosis and to assess the presence and profusion of opacities consistent with asbestosis 5.
Important Notes
- Asymmetrical apical thickening on a chest x-ray is a non-specific finding and may be associated with a range of conditions, including inflammatory and neoplastic processes 1, 2.
- A thorough clinical evaluation, including a detailed medical history and physical examination, is essential to determine the underlying cause of asymmetrical apical thickening on a chest x-ray 3, 4, 5.
From the Research
Asymmetrical Apical Thickening on Chest X-Ray
Asymmetrical apical thickening on a chest X-ray can indicate several conditions, including:
- Pleural thickening, which can be caused by various factors such as asbestos exposure 6, tuberculosis 7, 8, or other diseases
- Apical cap or apical pleural thickening, which is a common finding on routine chest X-rays, particularly in males and current or ex-smokers 9
- Post-tuberculosis radiological sequelae, which can include fibrosis, bronchiectasis, and pleural thickening 8
Possible Causes
The causes of asymmetrical apical thickening on a chest X-ray can be diverse, including:
- Asbestos exposure, which can lead to pleural plaques, round atelectasis, and malignant pleural mesothelioma 6
- Tuberculosis, which can cause apical opacity, pleural thickening, and other radiological sequelae 7, 8
- Other diseases, such as silicosis, pleural metastasis, or rarer conditions, which can mimic pleural plaques or cause focal pleural thickening 10
Radiological Features
The radiological features of asymmetrical apical thickening on a chest X-ray can vary, including:
- Homogeneous apical opacity at least 1 cm thick on chest radiographs 7
- Pleural thickening, which can be uniform or nodular, and may be associated with pleural calcifications or effusion 6
- Apical cap or apical pleural thickening, which can be defined as a pulmonary apical cap and is more common on the right side 9