Urinary Tract Infection in Diabetic Patients
UTI is one of the most common infections in diabetic patients. Patients with diabetes have an increased risk of urinary tract infection as compared to non-diabetic population. This is true for both asymptomatic bacteriuria (ASB) and symptomatic UTI. The rate of asymptomatic bacteriuria is three to four times higher in diabetic women as compared to non-diabetic women. However, there is not much difference in the prevalence of asymptomatic bacteriuria in diabetic and non-diabetic men. The relative risk of symptomatic UTI in diabetics is about 1.39–1.43 times more as compared to non-diabetics. As in non-diabetic patients, the essential step in the pathogenesis of UTI is the adherence of pathogenic microbes to the bladder mucosal lining. In most gram-negative uropathogens, this is achieved by various virulence factors such as H antigen, fimbriae, or adhesins.
The presence of glucosuria and impairment of the granulocyte function in the diabetic patients, although long suggested as the reason for increased risk of UTI, have not been conclusively proven in vivo. Some studies have suggested that decreased urinary levels of IL-6 and IL-8 in diabetic patients contribute to increased incidence of UTI. It has also been suggested that there is increased adherence of bacteria to the urothelium in diabetic patients. This is due to decreased ability of THP to bind type 1 fimbriated organisms, possibly because of an additional glycosylation of THP in diabetic patients, and a positive correlation with poorly controlled diabetes. The clinical presentation of UTI in diabetic patients can range from asymptomatic bacteriuria to severe life-threatening sepsis. The incidence of symptomatic UTI in the form of dysuria, frequency, abdominal discomfort, and urgency is higher in diabetic patients. Occasionally, UTI in this group of patients might also be associated with hematuria. In diabetic patients, there are increased chances of UTI running a complicated course and presenting with acute pyelonephritis. The risk of hospital admission for acute pyelonephritis can increase 20–30 times in diabetic patients less than 44 years of age.
Journal of Nephrology and Urology