Spontaneous pneumomediastinum after balloon inflation presenting as dysphagia and odynophagia in a child

A previously healthy boy in middle childhood presented to the paediatric emergency department with a 2-day history of dysphagia, odynophagia and neck pain. There were no complaints of fever, cough, coryza, dyspnoea, vomiting, pleuritic chest pain on inspiration or ear discharge. There was no history of trauma, foreign body ingestion or medical procedures. There was a history of blowing balloons 3 days prior to the onset of complaints. Physical examination revealed stable vital signs, normal respiratory rate, symmetrical air entry, normal vesicular breath sounds and palpable subcutaneous crepitus over the chest. There were no other peculiarities or significant findings on examination.