Urinary tract infections in patients with diabetes mellitus: epidemiology, pathogenesis and treatment

https://doi.org/10.1016/j.ijantimicag.2007.07.042Get rights and content

Abstract

Patients with diabetes mellitus (DM) have a higher prevalence of asymptomatic bacteriuria (ASB) and incidence of urinary tract infections (UTIs) compared with patients without DM. They also more often have bacteraemia, with the urinary tract as the most common focus for these infections, as well as a higher mortality outside the hospital compared with patients without DM. It appears that the increased prevalence of ASB in diabetic women is not the result of a difference in causative bacteria, as the same virulence factors and resistance to antimicrobials were found in Escherichia coli isolated from the urine of diabetic women with ASB compared with non-diabetic controls. Bacterial growth in vitro is increased after the addition of glucose, however glucosuria is not a risk factor for ASB or for the development of UTIs in vivo. No differences in granulocyte function tests were demonstrated among diabetic women with ASB, non-bacteriuric women and healthy control subjects, but women with both ASB and DM had lower urinary cytokine and leukocyte concentrations than women with ASB without DM. Finally, it was found that E. coli expressing type 1 fimbriae adhere better to uroepithelial cells of women with DM compared with those isolated from women without DM. There are no randomised trials that answer the question as to the optimal duration of treatment for UTIs in diabetic patients. It has been recommended to consider these patients as having a complicated UTI and therefore to treat them for a period of 7–14 days.

Introduction

Patients with diabetes mellitus (DM) often have urinary tract infections (UTIs). It has been suggested that the presence of glucosuria can explain this increased incidence, but this has never been scientifically confirmed. Furthermore, UTIs in diabetic patients are mostly considered as complicated UTIs and therefore experts recommend treating them for longer than UTIs in non-diabetic patients.

The aim of this article is to discuss the literature regarding the epidemiology and the studies performed by the author and her colleagues concerning the pathogenesis and the current knowledge of treatment of UTIs in patients with DM.

Section snippets

Prevalence and incidence

Patients with DM have a higher prevalence of asymptomatic bacteriuria (ASB) and incidence of UTIs and other infections compared with patients without DM. We found a prevalence of ASB of 26% in women with DM compared with 6% in those without DM [1]. Others have demonstrated that the incidence of symptomatic UTIs shows a small increase in patients with DM. Compared with patients without DM, the relative risk (RR) ranged between 1.39 (99% confidence interval (CI) 1.36–1.43) and 1.43 (99% CI

Microorganisms

The increased prevalence of ASB and UTI in diabetic patients may be the result of differences in host responses between diabetic and non-diabetic patients, or to a difference in the infecting bacterium itself. We have shown that the increased prevalence of ASB in diabetic women is not the result of difference in bacteria, as the same number of virulence factors were found in the infecting E. coli (most common causative microorganism of ASB) in our diabetic women with ASB as listed in the

Asymptomatic bacteriuria

As described above, we could not find any differences in renal function deterioration between diabetic women with and without ASB during a long-term follow-up of 6 years [7]. This is in concordance with an earlier study in which women with DM and ASB were randomised to be treated with antimicrobial therapy or placebo to keep them non-bacteriuric [17]. The investigators showed that the incidence of symptomatic UTIs (primary endpoint) and serum creatinine increase (secondary endpoint) were not

Conclusions

Patients with DM have a higher prevalence of ASB and a higher incidence of symptomatic UTIs, which more often lead to complications compared with those without DM. Therefore these UTIs are generally considered as complicated UTIs. The increased adherence of E. coli with type 1 fimbriae to diabetic uroepithelial cells, with a lower urinary cytokine secretion and leukocyte number, can partially explain this increased incidence/prevalence. ASB does not lead to complications and therefore screening

References (25)

  • S.E. Geerlings et al.

    Asymptomatic bacteriuria may be considered a complication in women with diabetes. Diabetes Mellitus Women Asymptomatic Bacteriuria Utrecht Study Group

    Diabetes Care

    (2000)
  • B.R. Shah et al.

    Quantifying the risk of infectious diseases for people with diabetes

    Diabetes Care

    (2003)
  • L.M. Muller et al.

    Increased risk of common infections in patients with type 1 and type 2 diabetes mellitus

    Clin Infect Dis.

    (2005)
  • E.J. Boyko et al.

    Diabetes and the risk of acute urinary tract infection among postmenopausal women

    Diabetes Care

    (2002)
  • N. Joshi et al.

    Infections in patients with diabetes mellitus

    N Engl J Med

    (1999)
  • J.A. Carton et al.

    Diabetes mellitus and bacteraemia: a comparative study between diabetic and non-diabetic patients

    Eur J Med

    (1992)
  • R. Meiland et al.

    Asymptomatic bacteriuria in women with diabetes mellitus: effect on renal function after 6 years follow-up

    Arch Intern Med

    (2006)
  • S.E. Geerlings et al.

    Consequences of asymptomatic bacteriuria in women with diabetes mellitus

    Arch Intern Med

    (2001)
  • L.E. Nicolle et al.

    Infectious Diseases Society of America guidelines for the diagnosis and treatment of asymptomatic bacteriuria in adults

    Clin Infect Dis

    (2005)
  • S.E. Geerlings et al.

    Virulence factors of Escherichia coli isolated from urine of diabetic women with asymptomatic bacteriuria: correlation with clinical characteristics

    Antonie Van Leeuwenhoek

    (2001)
  • R. Meiland et al.

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

    Diabet Med

    (2004)
  • S.E. Geerlings et al.

    Effect of glucose and pH on uropathogenic and non-uropathogenic Escherichia coli: studies with urine from diabetic and non-diabetic individuals

    J Med Microbiol

    (1999)

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