THE COPETTI SIGN: A PROSPECTIVE OBSERVATIONAL STUDY ON THE USE OF A NOVEL ULTRASOUND MARKER IN THE DIAGNOSIS AND MANAGEMENT OF RENAL COLIC IN THE EMERGENCY DEPARTMENT

Background Renal colic is a frequent and complex presentation in the Emergency Department (ED), requiring rapid diagnosis and targeted management. Point-of-care ultrasound (POCUS) is increasingly used for the assessment of suspected ureteral stones, but its diagnostic value depends on the identification of reliable sonographic signs. The Copetti sign, a novel ultrasound finding, has been proposed to improve the detection of distal ureteral stones. This study aimed to evaluate the association between the Copetti sign and distal ureteral stones, as well as its relationship with management strategy and stone size in patients presenting with suspected renal colic. Methods A prospective observational study was conducted, enrolling adult patients presenting to the ED with suspected renal colic from January to March 2025. All patients underwent POCUS with systematic assessment for the Copetti sign, defined as a rhythmic anteroposterior oscillation of the affected kidney along its long axis. Demographic, clinical, and laboratory data were collected, along with stone characteristics (size and location) and management strategy (conservative vs. interventional). The primary objective was to assess the association between the Copetti sign and the presence of distal ureteral stones. Secondary objectives included evaluating the relationship between the Copetti sign and management strategy, and between the Copetti sign and stone size. Results A total of 44 patients were included in the analysis. The Copetti sign was observed in 70.5% (31 out of 44) of cases. Among patients with the sign, 54.8% had left-sided renal colic and 45.2% had right-sided involvement. The presence of distal ureteral stones was significantly associated with the Copetti sign (p = 0.005): 74.2% of patients with the sign had distal stones, compared to only 25.8% of those without the sign. This finding highlights the strong association between the Copetti sign and distal stone location. Stone size also played a role in the presence of the Copetti sign. Patients with the sign tended to have smaller stones, with a median size of 6.00 mm (interquartile range [IQR] 3.25–8.75 mm), compared to a median of 8.00 mm (IQR 5.00–10.0 mm) in those without the sign. Although this difference approached statistical significance (p = 0.161), logistic regression analysis indicated that stone size ≤10 mm was inversely related to the presence of the Copetti sign (Estimate = -4.469, p = 0.04497), possibly due to the small sample size. Management strategies differed notably between groups. Conservative treatment was more common in patients with the Copetti sign, being adopted in 77.4% of these cases, compared to 22.6% in those without the sign (p = 0.019). Conversely, urological intervention was more frequently required in patients without the sign (74.2% vs. 36.4%, p = 0.040). Logistic regression analysis also identified conservative management as a positive predictor for the Copetti sign (Estimate = 3.005, p = 0.03037). Other variables, such as hydronephrosis grade and inflammation, did not show significant associations with the Copetti sign. Conclusion In summary, the Copetti sign is significantly associated with the presence of distal ureteral stones and a higher likelihood of conservative management. These findings suggest that the Copetti sign may serve as a useful clinical indicator for less invasive treatment approaches in patients with distal ureteral calculi, supporting its integration into the diagnostic and management pathway for renal colic in the ED.