[Pathophysiology, diagnosis and conservative therapy of non-calcium kidney calculi]

A case-control study on environmental and biological risk factors for renal calculi persisting in a coastal Union Territory, India

Background and Objectives:

Renal stone disease is a common disorder of the urinary tract and also a significant problem because of incidence, recurrence, and severe consequences. The complex pathogenetic mechanisms of renal stone formation involve both biologic and environmental risk factors. The present study was performed to identify the role of these parameters among renal stone patients and normal individuals from a coastal union territory region in South India.

Methods:

The authors conducted a case–control study of renal stone disease among outpatient department patients more than 30 years of age using systematic random sampling procedure with 100 study participants (50 subjects for each group). A questionnaire to explore some relevant history as well as to note general examination findings was used along with a house visit to collect a sample of water. Analysis was undertaken using appropriate statistical techniques.

Results:

The study showed statistically significant association for renal stones with female sex, illiteracy, body mass index (BMI) (>25 kg/m²), sodium (>50 mg/L), water consumption (<1.5 L/day), water source being borewell, consuming soft drink, sedentary work, and family history of renal stones. The adjusted odds ratios (ORs) were significantly higher for consuming soft drink (OR: 8.19; 95% confidence interval: 1.99–33.69), sedentary work (10.01; 1.27–78.91), and water consumption < 1.5 L/day (7.73; 2.24–26.69).

Interpretation and Conclusions:

We conclude that in this part of India, female gender, illiteracy, high BMI, high sodium in drinking water, inadequate water consumption, borewell drinking water, soft-drink consumption, sedentary work, and family history of renal stones can lead to a significant increase in the risk of renal stone disease.

Complicated catheter-associated urinary tract infections due to Escherichia coli and Proteus mirabilis

Catheter-associated urinary tract infections (CAUTIs) represent the most common type of nosocomial infection and are a major health concern due to the complications and frequent recurrence. These infections are often caused by Escherichia coli and Proteus mirabilis. Gram-negative bacterial species that cause CAUTIs express a number of virulence factors associated with adhesion, motility, biofilm formation, immunoavoidance, and nutrient acquisition as well as factors that cause damage to the host. These infections can be reduced by limiting catheter usage and ensuring that health care professionals correctly use closed-system Foley catheters. A number of novel approaches such as condom and suprapubic catheters, intermittent catheterization, new surfaces, catheters with antimicrobial agents, and probiotics have thus far met with limited success. While the diagnosis of symptomatic versus asymptomatic CAUTIs may be a contentious issue, it is generally agreed that once a catheterized patient is believed to have a symptomatic urinary tract infection, the catheter is removed if possible due to the high rate of relapse. Research focusing on the pathogenesis of CAUTIs will lead to a better understanding of the disease process and will subsequently lead to the development of new diagnosis, prevention, and treatment options.