Percutaneous nephrolithotomy: short- and long-term effects on health-related quality of life.

BACKGROUND AND PURPOSE: Percutaneous nephrolithotomy (PCNL) is the treatment of choice for large and complex kidney stones, having increased its safety and effectiveness over the last years. Nonetheless, there is little known about its impact on quality of life (QoL). This study aimed at evaluating the effects of PCNL on patients' QoL in the short and long term. PATIENTS AND METHODS: We prospectively studied 40 consecutive cases who underwent PCNL. QoL was measured using the short form-36 (SF-36) questionnaire, 2 weeks before surgery and then in the third postoperative month and a year after. Changes in QoL were assessed under statistical and clinical relevance criteria. RESULTS: PCNL has rendered 70% of the cases completely stone free with a 35% complication rate (33% Clavien I+II). The baseline scores of all SF-36 domains were worse than the referral population. Three months after PCNL, bodily pain was the only dimension whose change was relevant for patients (effect size [ES]=0.71, minimal clinically important difference [MCID]=0.56). A year after, this favorable effect of PCNL on body pain is still present, being also beneficial on both role physical (ES=0.58, MCID=0.52) and the physical component summary (ES=0.56, MCID=0.43). Social function was also close to reaching clinical relevance a year after the procedure (ES=0.66, MCID=0.72). CONCLUSION: Kidney stone disease considerably affects the patients' QoL. PCNL not only has good outcomes rendering the kidney stone free without major complications but produces an immediate body pain relief. This is perceived as relevant by the patients even a year after the procedure, when some other physical aspects of QoL also get better, helping patients to restore their social activities.

Predictive analysis of factors associated with percutaneous stone surgery outcomes.

INTRODUCTION: The aim of this study is to identify surgical, patient- and stone-related factors predictive of clinical success and complications after percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: We prospectively studied 100 consecutive PCNL procedures. Univariate and multiple regression models were used in order to identify which variables could act as independent predictors of PCNL outcomes. Success was defined as complete absence of fragments in a non-contrast CT. The Clavien-modified grading system was used to classify the complications. RESULTS: Univariate analysis showed that patients rendered stone-free had a significantly lower stone burden, shorter operating times, single stones and non-struvite composed calculi. Patient age, nephrostomy tract dilation with high pressure balloon and a stone composition different to struvite behaved as significant protective factors for complications. Logistic regression models revealed that the main independent prognostic factor for success was stone surface (OR = 0.997 per mm2, p = 0.000), followed by multiple stones (OR = 0.203, p = 0.050). On the other hand, struvite composition (OR = 5.911, p = 0.028) was an independent predictor for the development of complications, whilst age (OR = 0.936, p = 0.012) and high pressure balloon dilation (OR = 0.041, p = 0.007) were rendered independent protective variables. CONCLUSIONS: Stone burden and multiple calculi in the kidney affect the immediate stone-free rate, whilst Amplatz dilation, struvite stones and young patients lead to a higher incidence of postoperative complications. This information can be very useful for patient counseling, regarding percutaneous kidney stone management.