Spontaneous Pneumomediastinum and Subcutaneous Emphysema Associated With Diabetic Ketoacidosis: A Case Report.

Hamman's syndrome or Macklin phenomenon - spontaneous pneumomediastinum - is an uncommon condition that often gets missed due to the lack of awareness. It may rarely be associated with diabetic ketoacidosis (DKA) due to repeated vomiting or Kussmaul breathing associated with it. This condition is self-resolving, and improvement in symptoms is usually observed with appropriate management of DKA. Secondary pneumomediastinum is relatively more common, but spontaneous pneumomediastinum, which is rare, is often diagnosed incidentally. Here, we describe a case of a 24-year-old gentleman where this condition was found incidentally during the examination and was confirmed through imaging (X-ray and CT scans) and resolved with successful management of DKA.