The Accuracy of Point-of-Care Ultrasound in the Diagnosis of Acute Cholecystitis

Purpose: Acute cholecystitis (AC) affects 50-200 000 patients per year. Early surgery is the treatment of choice for AC. Therefore, timely diagnosis is important to begin proper management. Recently, emergency departments have adopted point-of-care ultrasound (POCUS) for the initial evaluation of AC. The accuracy of POCUS for AC has not been well studied.

Methods: Patients receiving POCUS for evaluation of AC in the emergency department at our tertiary care institution for 2 years were considered. Patients with previous biliary diagnoses were excluded. Patients were deemed to have AC from a recorded POCUS result or 2/3 of the following POCUS findings: pericholecystic fluid, gallbladder wall hyperemia, and sonographic Murphy's sign. Formal ultrasound and final diagnosis from surgical and pathology reports were used as gold standards for comparison.

Results: In total, 147 patients met inclusion criteria. POCUS had a sensitivity and specificity of .4 (95% CI: .1216-.7376) and .99 (.9483-.9982), respectively, when compared to a final diagnosis and .33 (.0749-.7007) and .94 (.8134-.9932) when compared to formal US. The modified Tokyo guidelines for suspicion of AC had a sensitivity of .2 (.0252-.5561) and specificity of .88 (.8173-.931) compared to the final diagnosis.

Conclusion: Point-of-care ultrasound was not a better screening test than the modified Tokyo guidelines. We recommend a simplified screening approach for AC using clinical findings and laboratory data, followed by confirmatory formal imaging. This strategy could prevent unnecessary delays in surgical management and use of physician resources.