Ultrasound guided percutaneous cutting biopsy for the diagnosis of pulmonary consolidations of unknown aetiology

BACKGROUND: Ultrasound has been used to guide percutaneous aspiration biopsy of thoracic tumours with high diagnostic yield. This study assessed the diagnostic value of ultrasound guided percutaneous cutting biopsy for pulmonary consolidation of unknown aetiology. METHODS: Thirty patients with undiagnosed lobar or segmental consolidation underwent ultrasound guided percutaneous needle aspiration and large bore cutting biopsy. The needle aspirates and biopsy specimens were sent for cytological, microbiological, and histopathological examination. RESULTS: Percutaneous needle aspiration provided a diagnosis in nine of 30 patients (30%), whereas cutting biopsy obtained a satisfactory specimen for histological diagnosis in 28 patients (93%) and provided a definite aetiological diagnosis in 17 patients (57%). The combination of needle aspiration with Trucut biopsy provided a diagnostic rate of 63%. The underlying diagnoses were fungal pneumonia (five patients), tuberculosis (five), bacterial pneumonia (one), bronchioloalveolar carcinoma (three), lymphoma (two), adenocarcinoma (one), vasculitis (one), acute pneumonia of unknown aetiology (one), and chronic non-specific pneumonia (nine). Two patients, who had necrotic tissue only in the biopsy specimen, were found at thoracotomy to have an adenocarcinoma and aspergillosis. Two patients had complications from the technique, a small pneumothorax in one and a small haemoptysis in another. CONCLUSIONS: Ultrasound guided percutaneous cutting biopsy is a valuable method for diagnosing pulmonary consolidation of unknown aetiology. The diagnostic yield is high and the procedure appears to be relatively safe.