MP43-04 MEDICAL DIGITAL SOLUTION TO MONITOR AND CONTROL URINARY PH IN CYSTINURIC PATIENTS

Abstract

INTRODUCTION AND OBJECTIVE: Cystinuria, is a congenital orphan disease that causes an excess of cystine excretion in urine. Urinary alkalinisation is a cornerstone of cystinuric patients: increase cystine solubility and making it difficult to crystallize. Hence the importance of urinary pH control to modulate the alkalizing treatments and maintain urine pH in alkaline range. Nowadays, urinary pH monitoring takes place with dipsticks, a subjective, non‐standardized, semiquantitative colorimetric method (compare results with a scale). Some limitations in terms of diagnostic accuracy parameters were reported in them. The objective of the study is to know the acceptance of a new pHmeter, that has demonstrated superiority in terms of sensitivity, specificity, positive predictive value, negative predictive value and accuracy against dipsticks as a system to monitor the urinary pH by cystinuric patients. METHODS: A randomized, controlled, open trial in 28 cystinuric patients were performed in Puigvert Foundation after been approved by the ethical committee. Once the patient's eligibility is verified, those receiving alkalinizing therapy under routine clinical practice were randomized in 2 groups: those who measure the urinary pH twice a day with the medical device and those who do it with strips (standard method). The patients were randomized with a ratio 1:1 by blocks. Control visits were performed at baseline, 1, 3 and 6 months. Measures of urinary pH, urine density, number of crystal and mean size were monitored. Questions about the facility of use and adherence to pharmacological treatment and nutritional recommendations were also studied. RESULTS: The 28 patients (32.1% women and 67.9% men) had an average age of 51.82 ± 18.58 (mean± standard deviation). Regarding the facility of use, the pHmeter was easier to learn how to manage (p=0.021), easier to prepare (p=0.034) and easier to use (p=0.062) than strips. Regarding adherence to the pharmacological and dietary recommendations there were a tendency to be better in the pHmeter group. Regarding the acceptance, the pHmetre patients scored general satisfaction with a mean of 7.3 ± 2.2 (where 0 was the lowest score and 10 the highest). As expected, the measurement of urine pH, its density, number of crystals and its mean size did not show statistically significant differences versus strips. CONCLUSIONS: The pH meter studied is an accepted medical device to monitor cystinuric patients easier to use than strips. This 2.0 digital solution opens a way to work on empowerment of patients.