Are patients with diabetic nephropathy (Impaired renal function due to diabetes) at a higher risk of developing Urinary Tract Infections (UTIs) and what is the treatment?

From the Guidelines

Patients with diabetic nephropathy are at a higher risk of developing urinary tract infections (UTIs) due to factors such as elevated glucose levels in urine, autonomic neuropathy, and impaired immune function. This increased risk is supported by recent studies, including the 2022 update on acute pyelonephritis, which highlights diabetes as a condition that predisposes patients to complications from urinary tract infections 1. The treatment for UTIs in patients with diabetic nephropathy typically involves empiric antibiotic therapy, with considerations for reduced kidney function. For example, trimethoprim-sulfamethoxazole (TMP-SMX) 160/800 mg twice daily for 3-5 days can be used for uncomplicated UTIs, or ciprofloxacin 500 mg twice daily for 7 days for more severe infections. However, in patients with reduced kidney function, dose adjustments may be necessary, such as reducing TMP-SMX to once daily if creatinine clearance is below 30 ml/min, as noted in guidelines for managing urinary tract infections in patients with compromised renal function 1. Additionally, management should include tight glycemic control, increased fluid intake, and complete bladder emptying to reduce the risk of recurrent UTIs and worsening diabetic nephropathy. Key considerations in treatment include avoiding nitrofurantoin in patients with GFR <30 ml/min due to reduced efficacy and increased toxicity risk, and considering prophylactic antibiotics for recurrent UTIs, such as TMP-SMX 40/200 mg daily or three times weekly. Regular monitoring of kidney function is essential to prevent the cycle of deteriorating renal function that can occur with untreated or recurrent UTIs in patients with diabetic nephropathy. The most recent and highest quality study, the 2022 update on acute pyelonephritis 1, supports the importance of prompt and appropriate treatment of UTIs in high-risk patients, including those with diabetic nephropathy, to prevent complications and improve outcomes. Some of the key points to consider in the treatment and management of UTIs in patients with diabetic nephropathy include:

• Elevated glucose levels in urine creating an ideal environment for bacterial growth
• Autonomic neuropathy causing incomplete bladder emptying
• Impaired immune function associated with diabetes reducing the body's ability to fight infections
• The need for dose adjustments in patients with reduced kidney function
• The importance of tight glycemic control, increased fluid intake, and complete bladder emptying in management
• The consideration of prophylactic antibiotics for recurrent UTIs
• Regular monitoring of kidney function to prevent worsening diabetic nephropathy.

From the Research

Diabetic Nephropathy and UTIs

• Patients with diabetic nephropathy are at a higher risk of developing Urinary Tract Infections (UTIs) due to their impaired renal function 2, 3, 4.
• The risk of UTIs in diabetic nephropathy patients is increased due to factors such as elevated glucose levels, long duration of diabetes, high blood pressure, obesity, and dyslipidemia 3.

Treatment of UTIs in Diabetic Nephropathy Patients

• The treatment of UTIs in diabetic nephropathy patients involves the use of antimicrobial agents, with the choice of agent depending on the severity of the infection and the susceptibility of the causative organism 5, 6.
• Recommended first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis includes a 5-day course of nitrofurantoin, a 3-g single dose of fosfomycin tromethamine, or a 5-day course of pivmecillinam 5.
• Second-line options include oral cephalosporins, fluoroquinolones, and β-lactams, such as amoxicillin-clavulanate 5.
• Parenteral treatment options for UTIs due to ESBLs-producing Enterobacteriales include piperacillin-tazobactam, carbapenems, ceftazidime-avibactam, and aminoglycosides including plazomicin 5.

Management of Diabetic Nephropathy

• The management of diabetic nephropathy involves early and intensive blood glucose and blood pressure control, including the use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers 2, 4.
• The rigorous management of modifiable risk factors, such as elevated glucose levels, high blood pressure, obesity, and dyslipidemia, is essential for preventing and delaying the decline in renal function 3.