Lung contusion after extracorporeal shock wave lithotripsy for pancreatic stones: A case report

BACKGROUND: Pancreatic extracorporeal shock wave lithotripsy (P-ESWL) is recommended as the first-line treatment for large pancreatic stones. While complications such as post-P-ESWL pancreatitis, bleeding, infection, steinstrasse, and perforation have been reported in the past 30 years, lung contusion has never been reported. The present case demonstrates lung contusion as a complication after P-ESWL. METHODS: A 48-year-old man was admitted to our department due to painful chronic pancreatitis with pancreatic duct stones. Computed tomography revealed normal lungs. P-ESWL was performed. The shock wave head contacted with right upper quadrant and the path of shock wave was at a 45° angle to the ventral midline. After P-ESWL, multiple patchy high-density shadows in the lower lobe of right lung were found, which was normal before P-ESWL. The patient had no symptoms of lung injury. RESULTS AND CONCLUSION: Laboratory studies revealed elevated D-dimer from 0.33 to 0.74 ug/mL, which was consistent with abnormal clotting of lung contusion. Chest computed tomography showed slight pleural effusion. Considering the interval between 2 X-rays was only 3 hours, we inferred that lung contusion was related to P-ESWL. The patient displayed stable vital signs, therefore, no specific interventions were conducted. Three days after P-ESWL, endoscopic retrograde cholangiopancreatography was performed and the lung shadows were partially absorbed. Considering the location of shock wave head, it was possible to cause lung contusion in lower lobe of right lung. More than 10,000 P-ESWL therapeutic sessions had been performed in our center since 2010, and it is the first case about lung contusion as a complication. It is also the first report to describe lung contusion after P-ESWL. Although the patient was asymptomatic, it should raise awareness of clinicians.