Postoperative left renal artery pseudoaneurysm enlarges within a short interval following toothpick induced duodenal perforation

Ingested toothpicks can perforate the gastrointestinal tract, with the duodenum being among the most frequently reported sites of lodgement and perforation. Visceral artery pseudoaneurysms following such injuries represent a recognized, potentially life-threatening complication. However, in contrast to direct foreign body erosion, postoperative pseudoaneurysms arising after operative hemostasis—and their short-interval growth kinetics under conservative observation—remain poorly documented. A 45-year-old man presented with abdominal pain and fever 10 days after accidentally swallowing a toothpick. Imaging revealed a 6.3-cm toothpick perforating the horizontal duodenum, penetrating the left retroperitoneum, and reaching the left renal hilum. During the initial laparoscopic approach, acute bleeding occurred upon extracting the toothpick from an encapsulated abscess, prompting an immediate and successful conversion to open laparotomy for hemostasis. On postoperative day 2, computed tomography angiography (CTA) identified a mid-segment left renal artery pseudoaneurysm measuring 0.3 × 0.23 cm. The vascular interventional specialist strongly recommended further endovascular or surgical repair; however, the patient firmly declined and requested conservative management. A strict conservative plan was adopted. However, repeat CTA demonstrated enlargement to 0.46 × 0.47 cm by postoperative day 19. This case documents the short-interval growth kinetics of a postoperative left renal artery pseudoaneurysm likely arising at the suture-repair site rather than by direct toothpick erosion. These observational findings document the early morphologic changes of a postoperative visceral pseudoaneurysm, highlighting the potential for short-term expansion under conservative observation.