Development and initial validation of a scoring system to diagnose testicular torsion in children.

Purpose: Testicular torsion is a surgical emergency requiring prompt intervention. Although clinical diagnosis is recommended, scrotal ultrasound is frequently ordered, delaying treatment. We created a scoring system to diagnose testicular torsion, decreasing the indication for ultrasound. Materials and Methods: We prospectively evaluated 338 patients with acute scrotum, of whom 51 had testicular torsion. Physical examination was performed by a urologist, and all patients underwent scrotal ultrasound. Univariate analysis and logistic regression were performed, and a scoring system for risk stratification of torsion was created. Retrospective validation was performed with 2 independent data sets. Results: The scoring system consisted of testicular swelling (2 points), hard testicle (2), absent cremasteric reflex (1), nausea/vomiting (1) and high riding testis (1). Cutoffs for low and high risk were 2 and 5 points, respectively. Ultrasound would be indicated only for the intermediate risk group. In the prospective data set 69% of patients had low, 19% intermediate and 11.5% high risk. Negative and positive predictive values were 100% for cutoffs of 2 and 5, respectively (specificity 81%, sensitivity 76%). Retrospective validation in 1 data set showed 66% of patients at low, 16% intermediate and 17% high risk. Negative and positive predictive values for cutoffs of 2 and 5 were 100% (specificity 97%, sensitivity 54%). The second retrospective data set included only torsion cases, none of which was misdiagnosed by the scoring system. Conclusions: This scoring system can potentially diagnose or rule out testicular torsion in 80% of cases, with high positive and negative predictive values for selected cutoffs. Ultrasound orders would be decreased to 20% of acute scrotum cases. Prospective validation of this scoring system is necessary.