Treatment for Calcium Phosphate Kidney Stone Disease

Phase 2

Completed

Conditions: Calcium Phosphate Kidney Stones

Interventions: Dietary Supplement: Placebo
Dietary Supplement: Citric Acid
Dietary Supplement: Potassium Citrate

Registration Number: NCT01754779

Lead Sponsor: University of Texas Southwestern Medical Center

Brief Summary: The investigators will examine in two studies whether citric acid or potassium citrate can reduce calcium phosphate saturation in urine of Calcium Phosphate stone formers.

Detailed Description: We will examine in two short-term placebo-controlled cross-over metabolic studies whether citric acid or potassium citrate can reduce calcium phosphate saturation in urine of CaP stone formers.

The first study will be conducted in hypocitraturic CaP stone formers without hypercalciuria, and will compare the effects of potassium citrate, citric acid and placebo.

The second study will be conducted in hypercalciuric CaP stone formers on a thiazide diuretic who require potassium supplementation, and will compare the effects of potassium chloride alone, potassium chloride + citric acid, and potassium citrate alone. Physicochemical assays will be applied in addition to computer-based stone risk prediction programs to assess risk of stone recurrence.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 13

Inclusion Criteria

Aim 1

Hypocitraturic CaP stone formers
urine citrate <320mg/d
elevated pH as 24-hr urine pH above 6.40
>21 years

Aim 2

Hypercalciuric CaP stone formers
24hr urine calcium >250mg/d in women and >300mg/d in men prior to indapamide use
high pH as >6.40 in the absence of urinary tract infection
>21 years

Exclusion Criteria

Not provided

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Placebo, then Citric Acid, then Potassium Citrate	Potassium Citrate	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Potassium Citrate, then Placebo, then Citric Acid	Placebo	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Placebo, then Citric Acid, then Potassium Citrate	Citric Acid	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Potassium Citrate, then Placebo, then Citric Acid	Potassium Citrate	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Citric Acid, then Placebo, then Potassium Citrate	Potassium Citrate	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Placebo, then Potassium Citrate, then Citric Acid	Citric Acid	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Citric Acid, then Placebo, then Potassium Citrate	Citric Acid	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Placebo, then Citric Acid, then Potassium Citrate	Placebo	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Placebo, then Potassium Citrate, then Citric Acid	Potassium Citrate	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Potassium Citrate, then Placebo, then Citric Acid	Citric Acid	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Potassium Citrate, then Citric Acid, then Placebo	Potassium Citrate	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Placebo, then Potassium Citrate, then Citric Acid	Placebo	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Potassium Citrate, then Citric Acid, then Placebo	Citric Acid	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Citric Acid, then Potassium Citrate, then Placebo	Potassium Citrate	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Potassium Citrate, then Citric Acid, then Placebo	Placebo	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Citric Acid, then Potassium Citrate, then Placebo	Placebo	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Citric Acid, then Potassium Citrate, then Placebo	Citric Acid	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)
Citric Acid, then Placebo, then Potassium Citrate	Placebo	Participants will receive at random, First intervention (1 week), then experience a washout period (1 week) and then receive Second Intervention (1 week) followed by another washout period of 1 week to finally receive the Third Intervention (1 week)

Primary Outcome Measures

Name	Time	Method
Urinary Calcium Phosphate Saturation	2 weeks	This variable represents a ratio of the calcium phosphate saturation in a given urine sample to the calcium phosphate saturation at the point of precipitation and hence this measure has no units.

Secondary Outcome Measures