Wall–Echo–Shadow (WES) Sign suggestive of Gallbladder Stones in a Contracted Gallbladder after GLP‑1 Agonist–Associated Weight Loss: A Point‑of‑Care Ultrasound Case from the Emergency Department
Dr Himanshu Gul Mirani
Case Presentation:
A man in his forties presented to the emergency department with right upper quadrant abdominal pain of acute onset. He had recently experienced rapid, intentional weight loss following initiation of a GLP‑1 receptor agonist for weight management. He denied fever, vomiting, jaundice, or systemic symptoms.
On examination, he was afebrile, haemodynamically stable, and non‑icteric, with localized right upper quadrant tenderness but no peritonism. The working diagnosis was biliary colic or early acute cholecystitis in the context of recent rapid weight loss, which is known to increase the risk of gallstone formation and biliary disease, including in patients on GLP‑1 receptor agonists.
WES Sign: Cholelithiasis
Management and Outcome:
Bedside point‑of‑care ultrasound (POCUS) of the right upper quadrant was performed using a curvilinear probe. Instead of a clearly distended, bile‑filled gallbladder, a contracted structure was seen in the gallbladder fossa with a characteristic wall–echo–shadow (WES) sign, representing the gallbladder wall, a highly echogenic interface from gallstones immediately deep to the wall, and clean posterior acoustic shadowing. This pattern indicated a gallbladder lumen essentially filled by stones, with minimal residual bile.
Recognition of the WES sign was important, as it can easily be overlooked or mistaken for adjacent bowel gas and duodenal shadowing, particularly when the gallbladder is not well visualized, leading to diagnostic uncertainty in the emergency setting.
Routine blood tests were unremarkable, and there was no biochemical evidence of biliary obstruction or systemic inflammation.
Given the POCUS findings and persistent right upper quadrant pain, the case was discussed with the on‑call surgical team. The patient was admitted for observation and formal departmental ultrasound the following day. The repeat ultrasound confirmed a contracted gallbladder with cholelithiasis and features consistent with biliary colic.
Note that computed tomography was not pursued as the primary imaging modality, in keeping with evidence that CT has limited sensitivity and specificity for gallbladder pathology and that gallbladder carcinoma and benign gallbladder disease can have overlapping CT appearances, leading to potential misdiagnosis. High‑resolution ultrasound remains the preferred first‑line modality when gallbladder disease is suspected.
Key Learnings and Points:
Point‑of‑care ultrasound in the emergency department allows rapid assessment of right upper quadrant pain, particularly in patients with GLP‑1–associated rapid weight loss who are at increased risk of gallstone disease
The wall–echo–shadow (WES) sign represents a contracted gallbladder filled with stones and can be subtle; failure to recognize it may lead to missed biliary pathology or misinterpretation as duodenal or bowel gas shadowing
CT is not the imaging modality of choice for primary evaluation of suspected gallbladder disease and may fail to distinguish benign inflammatory conditions from gallbladder carcinoma, reinforcing the central role of high‑quality ultrasound.