Licurse Score for Renal Ultrasound

Known Hydronephrosis

History of Recurrent UTIs

Known or Suspected Pelvic Malignancy

Non-black Race

Creatinine >1.4 mg/dL

History of Kidney Stones

Score:–

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Predicts probability of hydronephrosis on renal ultrasonography (RUS) requiring urologic intervention in adult patients with acute kidney injury.

Why Use

Estimates the probability of clinically significant hydronephrosis. Helps identify patients unlikely to benefit from renal ultrasound, reducing unnecessary imaging.

When to Use

Use in hospitalized adults with new or worsening acute kidney injury (AKI) to decide whether a screening renal ultrasound is needed to rule out obstructive uropathy.

Formula

Addition of the selected points: Variable Points History of hydronephrosis* Yes High-risk group No - Race Non-black 1 Black 0 History of recurrent urinary tract infections Yes 1 No 0 Diagnosis consistent with possible obstruction** Yes 1 No 0 History of congestive heart failure No 1 Yes 0 History of sepsis or prerenal acute kidney injury, use of pressors, or hypotension No 1 Yes 0 Exposure to nephrotoxic medications*** prior to acute kidney injury No 1 Yes 0 *Documented history of HN in the medical record or any imaging history of HN in the 2 years prior to the current RUS. **e.g. benign prostatic hyperplasia, abdominal or pelvic cancer, neurogenic bladder, single functional kidney, or previous pelvic surgery. ***Aspirin (>81 mg/day), diuretic, ACE inhibitor, or IV vancomycin.

Pearls / Pitfalls

Derived and validated only in inpatient adults evaluated for AKI; not validated in chronic kidney disease without AKI, pediatric, or ambulatory populations. Shows a high negative predictive value (~97–99 %) for hydronephrosis requiring intervention, so it is most useful for ruling obstruction out rather than in. High-risk groups (e.g., pregnant individuals, known or recent hydronephrosis, renal transplant) were excluded from the derivation and validation studies. Inclusion of “non-Black race” improved model performance in the derivation cohort but may not generalize; use this variable cautiously and never as a substitute for equitable clinical judgment.

Management

Low risk (score ≤2 pts): Consider deferring renal ultrasound. Focus evaluation and management on prerenal and intrinsic causes. Reassess if the clinical picture changes or AKI persists despite appropriate treatment for prerenal/intrinsic etiologies. Medium risk (score 3): Weigh the need for imaging against other clinical clues. Consider nephrology consultation. High risk (score ≥4): Obtain a renal ultrasound. Consult urology if obstruction is suspected or confirmed. If confirmed, proceed to decompression (e.g., catheter, nephrostomy, stent) and address reversible contributors (e.g., BPH treatment).

Advice

Interpret the score alongside clinical findings; if obstruction is strongly suspected or the patient is otherwise high-risk, obtain imaging regardless of score. Patients with known renal abnormalities (horseshoe kidney, solitary kidney, renal transplant) are high-risk and should undergo renal ultrasound irrespective of score, as delayed recognition of obstruction can have serious consequences.

More Information

Interpretation: Licurse Score Risk Group Risk of Hydronephrosis on Imaging Risk of Hydronephrosis Requiring Stent or Nephrostomy Tube Placement ≤2 Low 4.0% 1.1% 3 Medium 6.8% 0.5%* >3 High 20.9% 4.9% From Ip 2016 . *Data are from the validation study, which found a paradoxical decrease in risk of hydronephrosis requiring urologic intervention for medium- versus low-risk scores. Wider validation is needed to further clarify actual risk.