Paediatric thoracic tumours presenting as empyema.

Ultrasonography (US) is considered to be adequate for the preoperative evaluation of childhood empyema. This study was aimed to improve awareness that paediatric intra-thoracic tumours can mimic childhood post-pneumonic empyema and highlights the value of computed tomogram (CT) scan with intravenous (IV) contrast in preoperative evaluation of childhood empyema. The data were analysed on eight children (four boys and four girls) presented at the median age of 6.2 years (1.8-15 years) for the management of empyema and later confirmed to have intra-thoracic tumours. Intra-thoracic tumours in 8 (5.3%) children out of 150 cases of post-pneumonic empyema were managed during the study period. All eight had clinical features, increased white cell count, raised inflammatory markers and biochemical parameters suggestive of childhood empyema. Chest X-ray showed localised opacity in 3/8 while in other five suggested significant pleural collection with mediastinal shift. Additional investigations in referring hospital were suggestive of empyema in four children; US in three, CT scan without IV contrast in one. Referring hospital carried out non-diagnostic thoracocentesis in four children with blood stained pleural tap in two. In four children corroborative evidence suggestive of infection within pleural cavity and acute respiratory distress led to an emergency mini-thoracotomy resulting in significant intra-operative bleeding in two children. Histology on biopsy of the infected material showed primitive neuroectodermal tumour (PNET) in one, pleuropulmonary blastoma in one, metastatic malignant melanoma in one and cytology of pleural fluid diagnosed lymphoma in one. Pre-operative CT scan with IV contrast in four children correctly identified underlying intra-thoracic tumour (two benign teratoma, two PNET). In two cases CT with IV contrast was performed because chest X-ray suggested mediastinal loculated empyema while in other two high clinical index of suspicion prompted preoperative evaluation with CT scan with IV contrast. We advocate caution and increased awareness before considering therapeutic options in childhood empyema and recommend preoperative CT scan with IV contrast in some selected and unusual cases.