Where has the air gone?

Arch Dis Child January 2011 Vol 96 No 1 Pneumorrhachis (air within the spinal canal) is rare and usually associated with other air leaks. Diagnosis is usually by high resolution CT scan. A 9-year-old boy had a 10-day history of persistent cough despite treatment with inhaled bronchodilators, systemic steroids and antibiotics before coming to hospital. Physical examination demonstrated good general condition, cervical subcutaneous emphysema and reduced breath sounds with widespread crackles and wheeze. Chest x-ray demonstrated pneumomediastinum and overinfl ation of the left upper lung fi eld. CT showed pneumopericardium, pneumothorax and pneumorrhachis (fi gure 1). The patient recovered uneventfully and no underlying cause was found. Pneumorrhachis is rare, particularly in children: it can be classifi ed into internal, intradural (intraspinal air within the subdural or subarachnoid space) and external, extradural (intraspinal, epidural air).1 2 It is usually asymptomatic and can be due to trauma, extension of pneumothorax or pneumomediastinum, iatrogenic causes (lumbar puncture or epidural anaesthesia) and malignancy and its treatment.3–5 Subarachnoid pneumorrhachis can occur after trauma or extensive surgical exposure of the spinal nerve roots; it is often associated with a fatal outcome.3 In summary, we report the case of a child who developed pneumorrhachis after coughing, presumably secondary to a community acquired viral infection. Imaging showed epidural pneumorrhachis with air throughout the spinal canal.