This Study Evaluates the Superiority of Daily Self-pH Monitorization of Lit-control®pH Meter Compared to the Monitorization of Reactive Strips (Standard of Care).

Randomized, Controlled and Opened Trial on the Impact of the Use of a pH-Meter on the Domiciliary Control of the Urinary pH as Adjuvant to the Treatment of Cystinuric Patients

This study evaluates the superiority of daily self-pH monitorization of Lit-control®pH meter compared to the monitorization of reactive strips (standard of care).

Cystinuria is a disease of autosomal recessive inheritance. This disease belongs to the so-called orphan diseases although its prevalence may change depending on the country.

It is known that urinary pH is a risk factor for the formation of cystine crystals because their solubility is pH-dependent. In different studies it has been shown that the solubility of cystine in urine increases when alkalinizing urinary pH, thus reducing the likelihood of crystal formation. Therefore, the control of urinary pH along with hygienic-dietetic measures that alkalize the urine or decrease the urinary concentration of cystine (abundant intake of water, food, etc.) are highly recommended as a preventive method to prevent the formation of cystine crystals whose retention and growth results in the formation of stones.

The Lit-control®pH Meter is a pH meter that allows a patient to self-monitor its urinary pH in a comfortable and simple way. With this tool the patient is able to know if his urinary pH is within the recommended limits. In other medical fields it has been observed that home monitoring of clinically relevant physiological parameters is a way of empowering the patient that can positively affect their attitudes and behaviors (adherence to received treatment, quality of life) and potentially improve their medical condition. Specifically, in patients with chronic diseases, the self-monitoring has been associated with a significant reduction in hospitalizations and hospital readmissions.

Inclusion Criteria:

• Age ≥18 years old.
• Cystinuric patients, with or without urinary lithiasis at the time of inclusion.
• Patients who accept their participation in the study and give their informed consent.

Exclusion Criteria:

• Patients with pathologies that require pH control other than the one established in the study protocol to avoid the formation of kidney stones.