- Select the number of stone episodes and the stone type (from stone analysis, if done).
- For a first-time stone former, tick the ROKS risk factors that apply.
- Optionally enter 24-hour urine volume, sodium, citrate, and calcium, plus age and whether kidney function is reduced. The checklist updates as you go.
All computation runs in your browser; no values are stored or transmitted beyond your own device.
When to Use
Use at the first nephrology or medical review after a stone episode, to decide how far to take the metabolic evaluation and which prevention steps to prioritize, and at follow-up after a repeat 24-hour urine collection.
When NOT to rely on it
This page does not manage an acute obstructing or infected stone: fever with obstruction, a solitary kidney, anuria, or AKI need same-day urological decompression. Struvite (infection) stones and stones in children are outside the CARI summary used here.
Pearls & Pitfalls
Urine output is the target, not glasses drunk
CARI recommends a daily urine output of at least 2.5 L for all stone formers (more than 3 L for cystine). In the PUSH trial, a behavioral program with financial incentives raised urine volume only slightly (median 1.81 vs 1.58 L at 6 months, 1.55 vs 1.47 L at 24 months) and did not reduce recurrence (19% vs 20%). In Borghi's 1996 trial, a sustained urine output above 2 L cut recurrence from 27% to 12%. Verify the volume with a repeat 24-hour urine.
About the ROKS factors
ROKS was derived from 2239 first-time symptomatic stone formers in Olmsted County, Minnesota (recurrence 11% at 2 years, 20% at 5, 31% at 10, 39% at 15). Ten-year recurrence ranged from 12% in the lowest to 56% in the highest quintile of nomogram score. The cohort was mostly White and the published model includes race; this page lists the factors but does not reproduce the point weights, so it reports a count, not a percentage.
Pitfalls
(1) Do not restrict calcium; normal calcium intake binds oxalate in the gut. (2) CARI recommends against a low-oxalate diet for calcium oxalate stones; it confuses patients and lowers diet quality. (3) Nonsteroidal anti-inflammatory drugs (NSAIDs) are first-line for acute pain but carry AKI risk in reduced kidney function and older adults. (4) In hot weather and outdoor work, fluid needs rise; titrate to urine output.
Stone Recurrence Profile and Prevention Plan
ROKS risk factors (first episode)
High-risk features (any → comprehensive evaluation)
24-hour urine (optional)
Next Steps
- Every stone former: basic evaluation (history, blood chemistry including calcium, urate, bicarbonate, and parathyroid hormone; urine microscopy and pH), urine output of at least 2.5 L/day, sodium below 100 mmol (2300 mg)/day, normal calcium intake, and a diet rich in fruit and vegetables.
- Recurrent or high-risk: stone analysis and a comprehensive 24-hour urine; repeat the collection after diet changes to confirm the targets are reached.
- Medication only after nutrition therapy, except uric acid stones, profound hypocitraturia, cystinuria, severe hypercalciuria, or high symptom burden.
- Interpret the full 24-hour panel with the Urine Supersaturation calculator, set a fluid plan with the Fluid Target calculator, and read the kidney stones guide.
Evidence
CARI 2026 recommendations used in the checklist
| Recommendation | Strength, certainty |
|---|---|
| Low-dose non-contrast CT for suspected acute kidney stones | Strong, high |
| Ultrasound for recurrent uncomplicated stones or non-acute review | Conditional, moderate |
| Stone analysis for all people with recurrent stones | Strong, low |
| Metabolic evaluation to direct individualized prevention | Strong, low |
| NSAIDs first-line for acute pain; paracetamol or opioids second-line | Strong, moderate / low |
| Urine output ≥ 2.5 L/day (cystine > 3 L) | Strong, moderate |
| Sodium < 100 mmol (2300 mg)/day with calcium-based stones | Strong, low |
| Recommended calcium intake (1000 mg/day under age 70) with calcium stones | Strong, moderate |
| Against a low-oxalate diet for calcium oxalate stones | Strong, very low |
| Fruit and vegetables; limit nondairy animal protein | Strong, low |
| Potassium citrate for hypocitraturia and/or low urine pH despite nutrition therapy | Strong, moderate |
| Thiazide for persistent hypercalciuria after nutrition therapy | Conditional, low |
| Against routine xanthine oxidase inhibitors unless needed for gout | Conditional, low |
CARI lists early medication for uric acid stones, profound hypocitraturia (urine citrate < 0.5 mmol/24 h), severe hypercalciuria (urine calcium > 10 mmol/24 h), cystinuria, and high symptom burden. The thiazide recommendation is conditional because NOSTONE showed little benefit when sodium intake stayed high. This tool also flags urine citrate below 1.7 mmol/day and calcium above 7.5 mmol/day as commonly used laboratory reference limits; these two cut points are not CARI thresholds.
ROKS nomogram factors (Rule et al., 2014)
Younger age, male sex, White race, family history, prior asymptomatic stone on imaging, prior suspected stone episode, gross hematuria, non-obstructing stone on imaging, symptomatic renal pelvic or lower-pole stone, no ureterovesical junction stone, and uric acid composition.
