We present the case of a 52-year-old male admitted to a district hospital with severe abdominal pain and no significant prior medical history. Initial investigations, including laboratory tests, ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI), suggested the presence of either a para duodenal abscess or a gastrointestinal stromal tumor (GIST). Laboratory findings revealed elevated CRP (193 mg/L) and WBC counts but normal pancreatic enzyme and liver function test results. An initial US examination identified a hypoechoic, polycyclic lesion near the pancreatic body and tail, measuring 35 × 28 × 50 mm. A subsequent CT scan showed a 50 × 40 × 50 mm pathological mass adjacent to the duodenum, pancreatic body, and mesenteric artery, with associated lymph nodes, pointing toward either an abscess or GIST. MRI findings, including low ADC signals and restricted diffusion, supported the likelihood of GIST.
The patient was treated with antibiotics, leading to reduced pain and improved CRP levels. However, due to personal reasons, the patient delayed a scheduled endoscopic ultrasound (EUS) for two weeks. Upon admission, a transabdominal US scan revealed a 40-mm linear hyperechoic structure extending from the gastric antrum’s muscular layer into the retroperitoneal region, surrounded by a dense fluid collection. These findings were consistent with a foreign body, later identified as a toothpick during an EUS procedure. The patient initially could not recall ingesting a foreign body.
This case underscores the enduring diagnostic value of ultrasound in detecting rare conditions like foreign body-induced retroperitoneal lesions, even in the era of advanced cross-sectional imaging. Incorporating ultrasound as part of the diagnostic algorithm can lead to earlier, accurate diagnoses and better patient outcomes.
