Decision Rule - TWIST Score for Pediatric Testicular Torsion

TWIST Score for Pediatric Testicular Torsion:

-Testicular swelling . . . . . . . . . . . . . .  [Yes (+2 points)/No (0 points)]
-Hard testicle . . . . . . . . . . . . . . . . . . .  [Yes (+2 points)/No (0 points)]
-Absent cremasteric reflex  . . . . . . . .  [Yes (+1 point)/No (0 points)]
-Nausea or vomiting  . . . . . . . . . . . . .  [Yes (+1 point)/No (0 points)]
-High-riding testicle   . . . . . . . . . . . . .  [Yes (+1 point)/No (0 points)]

A score of >5 points had a positive predictive value for testicular torsion in the original derivation study, suggesting consideration of immediate urological consultation.
A score of <2 points had a negative predictive value of 100% in the original derivation study, suggesting these patients may be clinically cleared if they lack other concerning features.
Scores of 2-5 points should be considered for further evaluation with ultrasound in the appropriate clinical setting.

https://thesgem.com/2018/02/sgem205-twist-shout-testicular-torsion/

Caution should be used with this score, as it has not performed well on subsequent attempts at validation.  The only reason I consider it at all is that a high score would prompt me to consult a Pediatric Urologist earlier in the course of care, and this score MAY help convince them to see a patient emergently and prior to ultrasound.  I would not delay getting an ultrasound, and would be very cautious with a "low risk" score.