RESUMEN
Actinomycosis is a rare disease in children and young adolescents and its thoracic manifestations accounted for a minority of all cases. We report a case of a 12-year-old boy who presented with a right anterior chest wall mass for one week together with weight loss and low grade fever for one month. His symptoms and signs as well as the results of the radiological investigations (i.e. chest X-ray and computed tomography (CT) of thorax with contrast) mimicked pulmonary tuberculosis or chest wall tumor. The definite diagnosis of actinomycosis relies on the Gram stain microscopy and culture of the chest wall lesion aspirates. An early and accurate diagnosis can prevent the patient from unnecessary invasive procedures such as open lung biopsy or thoracotomy. The mainstay of the treatment of actinomycosis remains to be a combination of abscess drainage as well as prolonged antibiotics such as penicillin. Follow-up CT scan of thorax with contrast is useful in monitoring the progress of disease recovery.