Prevention of Urinary Stones With Hydration

This is a two arm randomized controlled trial that incorporates pragmatic features, an
adaptable intervention, patient choice, and remote monitoring of fluid intake through a
"smart" water bottle. The study period is 24 months and will enroll approximately 1642
participants. Randomization will be stratified within a study site by age (adult vs.
adolescent) and first time vs. recurrent stone former.

Intervention and control arm study participants will receive a smart water bottle that
records daily fluid consumption, usual care including guideline-based recommendations of
adequate fluid intake to decrease kidney stone recurrence, and periodic 24 hour urine
collections, imaging (low-dose CT scan or ultrasound) and follow-up questionnaires.

Inclusion Criteria:

1. Aged ≥ 12 years

2. At least 1 symptomatic stone event (passage or procedural intervention) within 3 years
prior to enrollment or a symptomatic stone event within 5 years if the patient also
has new stone formation detected on imaging during the last 5 years. Symptomatic stone
defined as any of the following:

1. Stone passage

2. Procedural intervention

3. Radiographically or ultrasonographically confirmed stone with any of the
following:

i. Gross hematuria

ii. Renal colic or atypical abdominal pain attributed to the stone, as determined by a
treating provider

iii. A clinical pattern of intermittent symptoms consistent with intermittent
obstruction at the ureteropelvic junction, as determined by a treating provider

3. Low 24‐hr urine volume

1. ≥18 years old: <1.8 L/day

2. <18 years old: <20 ml/Kg/day up to 1.8L/day

4. Able to provide informed consent (parental permission for children)

5. Owning and willing to use a smartphone or other device (e.g., tablet) compatible with
the study‐provided wireless enabled "smart" bottle

Exclusion Criteria:

1. Spinal cord injury

2. Currently undergoing active treatment for cancer except basal cell skin cancer, or
patients with a history of cancer who completed their initial therapy <1 year before
screening.

3. Known infectious (struvite), monogenic or other causes of stone disease for which
therapies are likely to significantly alter course of stone disease

1. Cystinuria

2. Primary hyperoxaluria

3. Primary xanthinuria

4. Primary hyperparathyroidism

5. Sarcoidosis

6. Medullary sponge kidney

4. History or presence of hyponatremia (serum sodium <130 mmol/L) or hypo‐osmolality
(serum osmolality <275 mosm/kg)

5. Study participants with comorbidities that preclude high fluid intake or prior surgery
precluding high fluid intake or leading to GI fluid losses

1. History of or current Crohn's disease, ulcerative colitis, short gut syndrome
(e.g. ileostomy, bowel bypass surgery to treat obesity, small bowel resection),
chronic diarrhea, or GI tract ostomy.

2. History of malabsorptive (e.g., Roux‐en‐Y gastric bypass) or restrictive (e.g.,
sleeve gastrectomy) bariatric surgery procedures

3. Congestive heart failure

i. NYHA class II or greater, and/or ii. Hospital admission in the past year for heart
failure d. Lung disease with a home oxygen requirement e. Chronic kidney disease (eGFR
<30 ml/min/1.7 m2 over a 3‐month period) i. For adults (age ≥18), we will use the
CKD‐Epi equation which requires the measurement of serum creatinine only. ii. For
children (age <18), we will use the bedside Schwartz (CKiD) formula. f. Nephrotic
syndrome (>3.5 grams of protein per 24 hours) g. Cirrhosis with ascites

6. Women who are currently pregnant or planning pregnancy within 2 years.

7. Renal transplant recipient

8. Bedridden study participants (ECOG ≥ 3)

9. Uncorrected anatomical obstruction of the urinary tract

10. History of recurrent urinary tract infections (> 3 UTI/year proven by urine culture)

11. Exclusions due to medication use:

1. Chronic use of lithium

2. Long‐term glucocorticoid use (> 7.5 mg prednisone daily for > 30 days prior to
enrollment)

3. Intake of narcotic medication on a daily basis for >30 days prior to enrollment

4. Supplemental Vitamin C (> 1 g daily)

12. Individuals with stones that have developed after the initiation of medications that
are strongly associated with USD such as carbonic anhydrase inhibitors (acetazolamide,
topiramate, zonisamide), high dose vitamin C (> 1 g daily), high dose calcium
supplementation (> 1,200 mg daily) AND who have discontinued or plan to discontinue
these medications.

13. Individuals with stones composed of medications that may crystallize in the urine
(guaifenesin, sulfonamides, triamterene, and the protease inhibitors indinavir and
nelfinavir) AND who have discontinued or plan to discontinue these medications.

Note: Individuals who are on long‐term medications that increase the risk of stone
disease, who cannot stop these medications due to other chronic conditions (e.g., HIV)
and who may reduce their risk for stone recurrence through increased fluid intake,
will be eligible to participate in the trial. Examples of these medications include:

1. Carbonic anhydrase inhibitors (acetazolamide, topiramate, zonisamide)

2. Medications that may crystallize in the urine (guaifenesin, sulfonamides,
triamterene, and the protease inhibitors indinavir and nelfinavir).

14. Study participants <2 yrs life expectancy

15. Non‐English Speakers

16. History of Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH)

17. Anatomical urologic abnormalities including ileal conduits, horseshoe kidney,
megaureter or solitary kidney.

18. Psychiatric conditions impairing compliance with the study

19. Vulnerable population (prisoner and/or cognitive impairment that the investigator
feels will impact the study participant's ability to participate in the protocol)

20. Individual who will be unable to participate in the protocol in the judgment of the
investigator.