S3549 A Peculiar Complication of Diabetic Ketoacidosis (DKA) Secondary to Pneumomediastinum: Spontaneous Pneumorrhachis

Abstract

Introduction: Pneumorrhachis is the presence of free air surrounding the dura matter within the spinal canal. It was first reported by Gordon et al in 1977 and the actual term was coined in 1987 by Newbold et al. Spontaneous pneumorrhachis with extensive pneumomediastinum is a rare but self-limiting condition. We present a unique case of spontaneous pneumorrhachis secondary to pneumomediastinum. Case Description/Methods: A 20-year-old male with a history of Type 1 diabetes mellitus who presented with a two-day history of sudden onset of shortness of breath and retrosternal chest pain. He also reported nausea and multiple episodes of non-bloody, non-bilious emesis over the last two days prior to presentation. He denied fever, cough, trauma, or overt signs of GI bleed. He was tachycardiac and tachypneic on arrival. Exam consistent with anterior chest wall and neck subcutaneous emphysema. Labs were significant for blood glucose 450 with bicarbonate of 8 and an elevated anion gap. He was admitted to the ICU for the management of diabetic ketoacidosis. CXR showed extensive pneumomediastinum. CT chest showed pneumomediastinum with chest wall and neck subcutaneous emphysema. It also showed an important finding of pneumorrhachis. Barium esophagram showed no evidence of esophageal perforation in this patient with pneumomediastinum. No surgical intervention was warranted. Pt was monitored in the ICU, however unfortunately he left against medical advice prior to further investigation. He reported doing well on clinic follow up. Discussion: Pneumorrhachis represents an asymptomatic, radiological finding that is diagnosed with increasing prevalence due to the advancement in radiological techniques and modalities. Spontaneous pneumomediastinum (SPM) is a rare complication of DKA. Bouts of emesis and Kussmaul breathing in diabetic ketoacidosis have been postulated to cause alveolar rupture due to increased intra-alveolar pressure that eventually reaches the spinal canal. The most dangerous differential diagnosis of SPM is Boerhaave’s syndrome that should be excluded with contrast-swallow studies, especially in the setting of vomiting. Treatment is usually conservative since patients are asymptomatic and air is spontaneously resorbed. This case reflects the importance of keeping a differential of spontaneous pneumorrhacis as an important yet subtle complication of DKA.Figure 1.: Extensive pneumomediastinum in the anterior middle and posterior compartment with air extending to the spinal canal and posterior soft tissues.