Kidney stone disease (KSD) and urinary tract infection (UTI) frequently coexist, and stone removal may reduce the risk of recurrent UTI, the authors of the systematic review concluded.
The review shows that the relationship between KSD and UTI is bidirectional, as stone formers have a high prevalence of UTI and patients who are evaluated for UTI have a high prevalence of KSD. A recent retrospective study of 819 stone formers and 2,477 individuals without a history of KSD showed a 6- to 7-fold increased risk of UTI, including patients with calcium oxalate or urate stones.
Bhaskar K. Somani, MD, University Hospital, Southampton, England, reported that several other studies included in the review showed that stone removal was associated with lower rates of UTIs, including significantly It can reduce the recurrence rate of UTI in patients with a history of infection. , and Current Urology Reports.
“Our SR [systematic review] co-authors clearly indicated that UTI and KSD Regardless of stone composition, active intervention with stone removal should be recommended in such patients, especially when urinary tract infection recurs or other risk factors are present,” the authors wrote. “To prevent further UTI episodes, stone cultures must be obtained, if possible, so that an effective targeted antibiotic regimen can be tailored to bacterial prevalence.”
Chronic/recurrent UTI vs. The formation of the stone dates back more than 30 years. A study involving 43 patients with bacteriuria and kidney stones differentiated patients with stone-related infection and bacteriuria from those with UTI and without KSD. The authors of this earlier report concluded that “active stone intervention aimed at eradicating infection could eliminate the risk of permanent UTI.”
Somani and co-authors note that the nature of the association remains unclear. However, the observed increased risk of urinary infections in KSD patients “must be determined whether UTI is the main driver of stone formation or whether bacterial colonization on stones increases the risk of severe sepsis”. In addition, there is no consensus on the optimal management of patients with kidney stones that may lead to UTI. Supporting the hypothesis that treatment of KSD could provide a solution for recurrent UTIs in this cohort. They also wanted to determine the current hypothesized mechanism of bacterial influence on stone formation and growth.
From 1,900 publications, the authors narrowed the list down to 17 articles. Past 10 to 20 years Multiple published studies have identified an association between KSD and UTI. Others have provided insights into the nature of the association.
One study of 1,325 adults with KSD The 7-year study showed that the incidence of positive urine cultures was 28%, significantly higher than in the general population. The researchers further found that UTIs most frequently occurred with Proteus Infections are associated with patients with magnesium ammonium phosphate stones. Somani and co-authors say oxalate-containing stones predominate in patients without infection.
In a study of 100 patients with urinary tract In a study of patients with systemic symptoms, 79% had infections, mainly by E. coli (30%), Proteus (19%) and Klebsiella (11%). Almost 20% of infected patients had KSD.
Just last year, a comparison of stone formers and non-stone formers with a median follow-up of 19 years showed an infection rate of 18.7 % in stone formers and 14.1 % in controls Of the 155 stone formers who developed a UTI, 63 had at least one recurrence of the stone, which Somani and colleagues interpret as evidence of “a strong link between these conditions.”
This difference translates to a risk of UTI of 5.73 (P
A comparison of A prospective study of 100 patients undergoing elective stone resection showed a prevalence of UTI of 36%. The most common bacterial species in urine samples was E. Escherichia coli , Enterococcus species and Klebsiella/Enterobacter species, while E. coli , P. kiwifruit and Cray Botrytis species are most commonly found in the stone matrix. The study also showed that recurrent UTIs were associated with “almost all kidney stone components.”
This review includes several studies investigating the hypothesis that surgical intervention for stones may reduce bacterial burden, recurrent UTI. , and bacteriuria. A cohort study involving 103 patients with a history of recurrent UTI and KSD demonstrated that stone removal resulted in UTI resolution. As the stone-free rate decreased during the 12-month follow-up period, so did the infection-free rate (P
On the other hand, a retrospective analysis of 120 patients with recurrent UTI and KSD showed that 52% had recurrent postlithotomy infection. E infection. Escherichia coli was associated with successful clearance of the infection, while Enterococcus was associated with unsuccessful clearance. The observations suggest that administration of antibiotics before or after stone removal may alter the effect of surgery on recurrent UTIs, Somani and coauthors noted.
“Future work should focus on enhanced techniques that should analyze the original molecular mechanisms underlying the crystallization of organic and inorganic components in urine to finally resolve the ‘chicken and egg’ dilemma,” the authors concluded in said in. “Perhaps, a real cost and quality of life analysis of the treatment and monitoring of these patients should also be considered.”
Charles Bankhead is a Senior Editor in Oncology and also covers Urology, Dermatology and Ophthalmology. He joined MedPage today in 2007. focus on
The authors report no industry relevance.