Urine pH, citrate, and beyond: challenges of pharmaceutical stone management in daily urological practice

Kidney stone disease, or nephrolithiasis, is a prevalent urological condition with variable pathogenesis. Among various factors, urine pH is not only considered to be a more influential factor in stone formation and can aid in the early diagnosis and management of specific stone types such as uric acid, cystine, calcium phosphate and struvite stones, but the role of urine pH in calcium oxalate stones, which comprise most cases, is more complex. Hypocitraturia in routine evaluation is another recognizable factor in lithogenesis, and administration of citrate, a widely used agent in the conservative management of stones. corrects hypocitraturia. Citrate also alkalizes the urine and can therefore be used to dissolve and prevent uric acid stones. However, citrate can induce the formation of insoluble calcium phosphate salts, such as brushite and hydroxyapatite, which can lead to mixed stones and the development of nephrocalcinosis. To address this complexity, innovative treatments that focus on a broader inhibition of lithogenesis with pH-modifying strategies may allow for more comprehensive management. In addition, modern technological tools such as pH meters and pH-tracking mobile applications can offer personalized treatment plans, potentially improving patient outcomes. The current lack of consensus on the standard and optimal management of pH measurement and modification underscores the need for further research and greater collaboration among experts. The development of evidence-based strategies will be essential to improve prevention and nephrolithiasis.

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