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UTIs in patients with kidney stones lead to lower HRQOL measures compared with patients with kidney stones and no UTIs.
In a study published in Urolithiasis, researchers linked the occurrence of urinary tract infection with a poorer health-related QOL among patients with kidney stones.
“Urinary tract infections (UTIs) are associated with urolithiasis. Although urinary pathogens are implicated in the formation of stones in approximately 15% of cases, infections co-occur in up to 50% of patients with urinary stones,” Mingrui Wang, Peking University People’s Hospital, Beijing, China, and colleagues wrote. “Although urinary pathogens are implicated in the formation of stones in approximately 15% of cases, infections co-occur in up to 50% of patients with urinary stones.”
Previous studies have indicated that urinary tract infections compromise patients’ QOL, the researchers added.
“However, few studies have evaluated the relationship between UTI and the HRQOL in patients with urological stones,” Wang and colleagues continued. “Despite the surgical benefits for improving HRQOL among patients with kidney stones, the impact of UTI on the HRQOL improvement caused by stone removal surgery is still unknown.”
Patient Population and Intervention
The researchers conducted a prospective study of 307 volunteer patients using a validated Chinese version of the Wisconsin Stone Quality of Life questionnaire (C-WISQOL). Wang and colleagues asked study participants to fill out the questionnaire before and after kidney stone removal after diagnosing them with a urinary tract infection based on bacteriuria or pyuria. Then, the researchers performed a multivariate linear progression analysis to predict risk factors for worsened HRQOL in patients with urinary stones and UTIs.
Patients averaged 51 years (range, 18-80), and their mean BMI was 25.4 kg/m2. Most (56.4%) of the patients were women. About one-third of patients (30%, n=131) were diagnosed with a UTI while having kidney stones, the researchers reported. There were significant differences between groups in terms of the proportion of women and patients with diabetes, Wang and colleagues added. The UTI group was 63.4% women versus 51.1% of the non-UTI group (P=0.033). In the UTI group, on the other hand, 29% of patients had diabetes, compared with 17% in the no-UTI group (P=0.013).
Patients with UTIs experienced stone-related events more than the no-infection group, Wang and colleagues wrote. Those with infections had previously experienced 3.9 stone events, on average, and those without infections experienced two events (P<0.001). Furthermore, more than three-quarters of patients with UTIs received a prescription for antibiotics, compared with about two-thirds (60.2%) of patients without UTIs (P=.002).
Patients with both kidney stones and urinary tract infections experienced infection and stone-related symptoms at greater rates as well. Those with both infections and kidney stones experienced symptoms at a rate of 80.2%, compared with 52.8% of the no-UTI group (P<0.001). In the UTI group, Wang and colleagues wrote, 75.6% of patients had previously used analgesics, compared with 48.3% of the no-UTI group (P<0.001).
Patients in both groups underwent similar surgeries for stone removal; however, 40.5% of those with UTIs had residual stones after surgery, significantly greater than the 24.4% of those without UTIs who had residual stones (P=0.003).
HRQOL for Patients With Kidney Stones
Before surgery, Wang and colleagues wrote, patients without UTIs had significantly better C-WISQOL scores than those with UTIs (96.6 versus 92.5; P=0.01). This was true after surgery as well: patients with UTIs had a post-surgical QOL score of 112.9 (P=0.001), compared with 118.6 in the no-UTI group (P<0.001). Researchers noted that this difference was consistent across all domains of the C-WSQOL score. However, they wrote that the only significant differences in score change between these two groups were the overall score (20.4 for the UTI group versus 22 for the no-UTI group, P = .04) and social domain score (5.4 versus 6, P =0.042).
There were no significant changes in quality-of-life scores between the groups for the stone-related symptom impact, emotional impact, and social impact domains.
“The C-WISQOL questionnaire is a reliable tool for evaluating the HRQOL in Chinese-speaking patients with urolithiasis,” the researchers concluded. “Among patients with kidney stones who completed the C-WISQOL, clinically diagnosed UTI was significantly associated with a poorer HRQOL, predicted by a history of more previous stone events and positive stone- or UTI-related symptoms. The presence of diabetes mellitus and postoperative residual stone fragments predicted a lower improvement in the HRQOL. Based on the findings from this study, novel approaches could be developed to benefit the treatment of kidney stones and UTIs.”