BACKGROUND Spontaneous pneumomediastinum has been infrequently reported as a complication of diabetic ketoacidosis. Evidence-based guidelines are currently not available to help in choosing the best diagnostic approach. METHODS We conducted a systematic review of the literature and looked for diagnostic clues that might indicate the need for a work-up to rule out oesophageal perforation. RESULTS In all 56 published cases of spontaneous pneumomediastinum associated with diabetic ketoacidosis, the condition was self-limiting. We report one additional case of a 31-year-old female who presented with a spontaneous pneumomediastinum and also epidural pneumatosis, complicating diabetic ketoacidosis. CONCLUSIONS Important pathology, such as oesophageal rupture, was not detected in any of the reported cases, and we suggest a restrictive diagnostic work-up.