Ruby Meiland

Pathogenesis and management of bacterial urinary tract infections in adult patients with diabetes mellitus.

Urinary tract infections (UTIs) are more common and tend to have a more complicated course in patients with diabetes mellitus (DM). The mechanisms, which potentially contribute to the increased prevalence of both asymptomatic and symptomatic bacteriuriai in these patients are defects in the local urinary cytokine secretions and an increased adherence of the microorganisms to the uroepithelial cells. The need for treatment of asymptomatic bacteriuria remains controversial. No evidence is available on the optimal treatment of acute cystitis and pyelonephritis in patients with DM. Because of the frequent (asymptomatic) upper tract involvement and the possible serious complications, many experts recommend a 7-14-day oral antimicrobial regimen for bacterial cystitis in these patients, with an antimicrobial agent that achieves high levels both in the urine and in urinary tract tissues. Current data suggest that shorter regimens will lead to failure also in uncomplicated UTI in women. The recommended treatment of acute pyelonephritis does not differ from that in nondiabetic patients. Clinical trials specifically dealing with the treatment of UTIs in diabetic patients, comparing the optimal duration and choice of antimicrobial agent, are needed. Besides that, new approaches to preventive strategies must prove their value in this specific patient group.

Pathogenesis of bacteriuria in women with diabetes mellitus

Women with diabetes mellitus (DM) have asymptomatic bacteriuria (ASB) and symptomatic urinary tract infections (UTIs) more often than women without DM. The increased prevalence of bacteriuria in diabetic patients can be the result of differences in the host responses between diabetic and nondiabetic patients, or a difference in the infecting bacterium itself. We have shown that the increased prevalence of ASB in diabetic women is not the result of a difference in bacteria, because the same number of virulence factors was found in the infecting Escherichia coli (most common causative microorganism of ASB) in our diabetic women with ASB, as listed in the literature for nondiabetic patients with ASB. We found that bacterial growth in vitro was increased after the addition of different glucose concentrations, as found in urine of poorly controlled patients. However, we could not confirm that glucosuria was a risk factor for ASB in vivo. In addition, we demonstrated that women with both DM and ASB have lower urinary cytokine and leukocyte concentrations than women without DM but with ASB. Finally, we found that E. coli expressing type 1 fimbriae (the virulence factor that plays an important role in the pathogenesis of UTIs) adhere better to uroepithelial cells of women with DM compared with the cells of women without DM.

Diabetes mellitus in itself is not a risk factor for antibiotic resistance in Escherichia coli isolated from patients with bacteriuria

Aim  To investigate whether diabetes mellitus is a risk factor for resistance in Escherichia coli isolated from patients with bacteriuria.

Management of Bacterial Urinary Tract Infections in Adult Patients with Diabetes Mellitus

Urinary tract infections (UTIs) are more common and tend to have a more complicated course in patients with diabetes mellitus than in the general population. The mechanisms that potentially contribute to the increased prevalence of both asymptomatic and symptomatic bacteriuria in these patients are defects in the local urinary cytokine secretions and an increased adherence of the microorganisms to the uroepithelial cells. The need for treatment of asymptomatic bacteriuria remains controversial. No evidence is available on the optimal treatment of acute cystitis and pyelonephritis in patients with diabetes. Because of the frequent (asymptomatic) upper tract involvement and the possible serious complications, many experts recommend a 7- to 14-day oral antibacterial regimen for bacterial cystitis in these patients, with an antibacterial agent that achieves high concentrations both in the urine and in urinary tract tissues. The recommended treatment of acute pyelonephritis does not differ from that in patients without diabetes. Clinical trials specifically dealing with the treatment of UTIs in patients with diabetes, comparing the optimal duration and choice of antibacterial agent, are needed. In addition, new approaches to preventive strategies must prove their value in this specific patient group.

History taking and leukocyturia predict the presence of asymptomatic bacteriuria in women with diabetes mellitus

Objective: To investigate the accuracy of history taking to diagnose asymptomatic bacteriuria (ASB) in diabetic women, and the added value of leukocyturia. Methods: Data were obtained from a multicenter study including 465 women with diabetes. Many patient characteristics were considered as potential diagnostic determinants. A urinary leukocyte count and a urine culture (the criterion standard) were performed. Logistic regression analyses were performed and areas under the receiver operating characteristic curves (AUC) were calculated. Results: For women with type 1 diabetes (n=236; ASB 11%), duration of diabetes and glycosylated hemoglobin (GHb) were powerful predictors of ASB. The AUC of the model including these two variables was 0.66 (95% confidence interval (CI) 0.53–0.78). After addition of leukocyturia, the AUC increased considerably to 0.78 (95% CI 0.68–0.88; p = 0.018). For women with type 2 diabetes (n = 229; ASB 19%), age and the number of symptomatic urinary tract infections (UTIs) in the previous year were the strongest predictors of ASB. The AUC of the model including these variables was 0.70 (95% CI 0.61–0.80). After addition of leukocyturia, the AUC increased to 0.79 (95% CI 0.71–0.86; p=0.023). Conclusion: In diabetic women, ASB can be diagnosed using two easily obtainable variables (duration of diabetes and GHb for women with type 1 diabetes, and age and the number of UTIs in the previous year for women with type 2 diabetes) in combination with a urinary leukocyte count. This results in a model with sufficient accuracy (AUC > 0.75).

Escherichia coli bacteriuria in female adults is associated with the development of hypertension

OBJECTIVE To investigate whether Escherichia coli bacteriuria is associated with the development of hypertension during a long-term follow-up. METHODS A prospective cohort study was performed among the participants of two population-based studies. Between 1974 and 1986 all women aged 39 to 68 years old, who lived in Utrecht, the Netherlands, were invited to participate in a breast cancer screening program. The participants completed a questionnaire, underwent a medical examination, and collected a morning urine sample that remained stored. From 1993 to 1997 another population-based study was performed. We performed a full cohort analysis for 444 women who participated in both studies. E. coli bacteriuria was diagnosed by a real-time PCR. Hypertension was defined as the use of antihypertensive medication and/or a measured systolic blood pressure of at least 160 mmHg or a diastolic blood pressure of 95 mmHg or higher. The mean follow-up was 11.5+/-1.7 years. RESULTS Forty women (9%) had E. coli bacteriuria at baseline. Women who had bacteriuria at baseline had a mean blood pressure at study endpoint of 133+/-20 mmHg systolic and 78+/-11 mmHg diastolic, and women without bacteriuria had values of 129+/-20 and 78+/-11 mmHg, respectively (p-values for difference 0.33 and 0.88). Although E. coli bacteriuria was not associated with the blood pressure as a continuous variable, it was associated with the development of hypertension during follow-up (OR 2.8, 95% CI 1.4-5.5). CONCLUSION E. coli bacteriuria may increase the risk of future hypertension.