Prevalence of asymptomatic bacteriuria in subjects with NIDDM in San Luis Valley of Colorado

Clinical profile and spectrum of bacteriuria in patients with diabetes: An analytical study

Introduction

Diabetes is one of the modern-day epidemics with a spectrum of complications. Urinary tract infections (UTI) are common among patients with diabetes, and often it goes unnoticed in the initial period, which can later lead to complications. This study was planned to find out the magnitude of the problem of bacteriuria among diabetics and to look for its associated factors in diabetics.

Methodology

A hospital-based study recruiting 100 eligible diabetics consecutively over a period of one year. Socio-demographic data were collected using a semi-structured questionnaire, and clinical examinations with relevant investigations were done. Informed written consent was taken.

Results

Bacteriuria was found in 43 out of 100 participants. Prevalence was significantly more among females (54%) as compared to males (32%). Factors like poor glycaemic control, complications like neuropathy, diabetic foot were significantly associated with bacteriuria. E Coli was the most common bacterial isolate.

Conclusion

Urinary tract infection is common in diabetic patients, especially females, and other clinical factors like uncontrolled sugar levels also play a role.

Results, meta-analysis and a first evaluation of UNOxR, the urinary nitrate-to-nitrite molar ratio, as a measure of nitrite reabsorption in experimental and clinical settings

We recently found that renal carbonic anhydrase (CA) is involved in the reabsorption of inorganic nitrite (NO₂^-), an abundant reservoir of nitric oxide (NO) in tissues and cells. Impaired NO synthesis in the endothelium and decreased NO bioavailability in the circulation are considered major contributors to the development and progression of renal and cardiovascular diseases in different conditions including diabetes. Isolated human and bovine erythrocytic CAII and CAIV can convert nitrite to nitrous acid (HONO) and its anhydride N₂O₃ which, in the presence of thiols (RSH), are further converted to S-nitrosothiols (RSNO) and NO. Thus, CA may be responsible both for the homeostasis of nitrite and for its bioactivation to RSNO/NO. We hypothesized that enhanced excretion of nitrite in the urine may contribute to NO-related dysfunctions in the renal and cardiovascular systems, and proposed the urinary nitrate-to-nitrite molar ratio, i.e., U_NOxR, as a measure of renal CA-dependent excretion of nitrite. Based on results from clinical and experimental animal studies, here, we report on a first evaluation of U_NOxR. We determined U_NOxR values in preterm neonates, healthy children, and adults, in children suffering from type 1 diabetes mellitus (T1DM) or Duchenne muscular dystrophy (DMD), in elderly subjects suffering from chronic rheumatic diseases, type 2 diabetes mellitus (T2DM), coronary artery disease (CAD), or peripheral arterial occlusive disease (PAOD). We also determined U_NOxR values in healthy young men who ingested isosorbide dinitrate (ISDN), pentaerythrityl tetranitrate (PETN), or inorganic nitrate. In addition, we tested the utility of U_NOxR in two animal models, i.e., the LEW.1AR1-iddm rat, an animal model of human T1DM, and the APOE*3-Leiden.CETP mice, a model of human dyslipidemia. Mean U_NOxR values were lower in adult patients with rheumatic diseases (187) and in T2DM patients of the DALI study (74) as compared to healthy elderly adults (660) and healthy young men (1500). The intra- and inter-variabilities of U_NOxR were of the order of 50% in young and elderly healthy subjects. U_NOxR values were lower in black compared to white boys (314 vs. 483, P = 0.007), which is in line with reported lower NO bioavailability in black ethnicity. Mean U_NOxR values were lower in DMD (424) compared to healthy (730) children, but they were higher in T1DM children (1192). ISDN (3 × 30 mg) decreased stronger U_NOxR compared to PETN (3 × 80 mg) after 1 day (P = 0.046) and after 5 days (P = 0.0016) of oral administration of therapeutically equivalent doses. In healthy young men who ingested NaNO₃ (0.1 mmol/kg/d), U_NOxR was higher than in those who ingested the same dose of NaCl (1709 vs. 369). In LEW.1AR1-iddm rats, mean U_NOxR values were lower than in healthy rats (198 vs. 308) and comparable to those in APOE*3-Leiden.CETP mice (151).

Simultaneous pentafluorobenzyl derivatization and GC-ECNICI-MS measurement of nitrite and malondialdehyde in human urine: Close positive correlation between these disparate oxidative stress biomarkers

Urinary nitrite and malondialdehyde (MDA) are biomarkers of nitrosative and oxidative stress, respectively. At physiological pH values of urine and plasma, nitrite and MDA exist almost entirely in their dissociated forms, i.e., as ONO^- (ONOH, pK_a=3.4) and ^-CH(CHO)₂ (CH₂(CHO)₂, pK_a=4.5). Previously, we reported that nitrite and MDA react with pentafluorobenzyl (PFB) bromide (PFB-Br) in aqueous acetone. Here, we report on the simultaneous derivatization of nitrite and MDA and their stable-isotope labeled analogs O¹⁵NO^- (4μM) and CH₂(CDO)₂ (1μM or 10μM) with PFB-Br (10μL) to PFBNO₂, PFB¹⁵NO₂, C(PFB)₂(CHO)₂), C(PFB)₂(CDO)₂ by heating acetonic urine (urine-acetone, 100:400μL) for 60min at 50°C. After acetone evaporation under a stream of nitrogen, derivatives were extracted with ethyl acetate (1mL). A 1-μL aliquot of the ethyl acetate phase dried over anhydrous Na₂SO₄ was injected in the splitless mode for simultaneous GC-MS analysis in the electron capture negative-ion chemical ionization mode. Quantification was performed by selected-ion monitoring (SIM) the anions [M-PFB]^-m/z 46 for ONO^-, m/z 47 for O¹⁵NO^-, m/z 251 for ^-C(PFB)(CHO)₂, and m/z 253 for ^-C(PFB)(CDO)₂. The retention times were 3.18min for PFB-ONO₂/PFB-O¹⁵NO₂, and 7.13min for ^-C(PFB)(CHO)₂/^-C(PFB)(CDO)₂. Use of CH₂(CDO)₂ at 1μM but not at 10μM was associated with an unknown interference with the C(PFB)₂(CDO)₂ peak. Endogenous MDA can be quantified using O¹⁵NO^- (4μM) and CH₂(CDO)₂ (10μM) as the internal standards. The method is also useful for the measurement of nitrate and creatinine in addition to nitrite and MDA. Nitrite and MDA were measured by this method in urine of elderly healthy subjects (10 females, 9 males; age, 60-70 years; BMI, 25-30kg/m²). Creatinine-corrected excretion rates did not differ between males and females for MDA (62.6 [24-137] vs 80.2 [52-118]nmol/mmol, P=0.448) and for nitrite (102 [71-174] vs. 278 [110-721]nmol/mmol P=0.053). We report for the first time a close correlation (r=0.819, P<0.0001) between MDA and nitrite in human urine. This correlation is assumed to be due to involvement of myeloperoxidase which catalyzes the formation of hypochlorite (^-OCl) from chloride and hydrogen peroxide. In turn, hypochlorite reacts both with nitrite and with polyunsaturated fatty acids such as arachidonic acid, with the later reaction generating MDA. The proposed mechanisms are supported by the literature but remain to be fully explored.

Clinical profile of urinary tract infections in diabetics and non-diabetics

BACKGROUND

The risk of urinary tract infection (UTI) is higher in diabetics compared to non-diabetics. The aetiology and the antibiotic resistance of uropathogens have been changing over the past years. Hence the study was undertaken to determine if there are differences in clinical and microbiological features of UTI between diabetic and non-diabetic subjects, to study the influence of diabetes mellitus on the uropathogens and antibiotic sensitivity pattern in patients with UTI.

METHOD

A total of 181 diabetics (83 males and 98 females) and 124 non-diabetic subjects (52 males and 72 females) with culture positive UTI were studied. Patients with negative urine culture (n= 64), those diagnosed and treated outside (n= 83) and not willing to participate in the study (n= 24) were excluded.

RESULTS

Almost 30 per cent of the patients (both diabetics and nondiabetics) presented with asymptomatic bacteriuria and the prevalence of pyelonephritis was significantly higher (p= 0.04) in diabetics compared to non-diabetic patients. The majority of the diabetics with UTI (87.14 per cent) had glycosylated haemoglobin (HbA1c) > 6.5 per cent with p < 0.001. The isolation rate of Escherichia coli (E. coli) from urine culture was higher (64.6 per cent) among diabetic patients followed by Klebsiella (12.1 per cent) and Enterococcus (9.9 per cent). The prevalence of extendedspectrum beta-lactamase (ESBL) producing E.coli was significantly higher in diabetics (p= 0.001) compared to nondiabetics. E.coli showed maximum sensitivity to carbapenems in both diabetic and non-diabetic subjects and least susceptibility to ampicillin.

CONCLUSION

The prevalence of pyelonephritis is significantly higher in diabetics than in non-diabetic subjects, with E. coli being the most common isolate. Elevated glycosylated hemoglobin (HbA1c) predisposes diabetics to UTI. Investigation of bacteriuria in diabetic patients for urinary tract infection is important for treatment and prevention of renal complications.

The prevalence of asymptomatic pyuria in diabetic patients: comparison of the Sysmex UF-100 automated urinalysis analyzer with Fuchs-Rosenthal hemacytometer

OBJECTIVE

We investigated the prevalence of asymptomatic pyuria (ASP) in diabetic patients and compared the Sysmex UF-100 with Fuchs-Rosenthal hemacytometer.

DESIGN AND METHODS

ASP prevalence was investigated in 227 diabetic patients. Imprecision, accuracy and correlation of UF-100 with hemacytometer in measuring leukocyte counts were determined.

RESULTS

Diabetic women and men had significantly higher ASP prevalence than non-diabetic women (21.4 vs. 8.7%) and men (12.2 vs. 3.4%). Disease duration and HbA(1C) levels were similar in diabetic patients with and without ASP. UF-100 and hemacytometer readings correlated significantly (r=0.88) without a significant bias. Within-run coefficients of variations for UF-100 (8.14, 6.35 and 12.18%) and hemacytometer (5.14, 5.18 and 8.03%) did not differ significantly.

CONCLUSIONS

Prevalence of ASP is increased in diabetic patients and not affected by duration of disease or control of hyperglycemia. UF-100 seemed to be a reliable, precise and accurate system to determine pyuria.

Incidence and risk factors associated with urinary tract infection in diabetic patients with and without asymptomatic bacteriuria

In order to compare the incidence of symptomatic urinary tract infection (UTI) in diabetic patients with and without asymptomatic bacteriuria (ASB), and to identify other risk factors for these infections, 289 females and 168 males were studied over a 12-month period. Symptomatic UTI occurred in 69.2% of patients with ASB (67.6% female and 76.5% male) versus 9.8% without ASB (14.9% female and 2.6% male). ASB and urinary incontinence were associated with symptomatic UTI in both women and men. Other risk factors included previous antimicrobial treatment and macrovascular complications in women and obesity and prostatic syndrome in men. The presence of ASB was found to be the major risk factor for developing symptomatic urinary tract infection. Further prospective randomized clinical trials of diabetic patients with risk factors for UTI who are receiving or not receiving treatment may be considered.

Asymptomatic bacteriuria in type 2 Iranian diabetic women: a cross sectional study

Background

The risk of developing infection in diabetic patients is higher and urinary tract is the most common site for infection. Serious complications of urinary infection occur more commonly in diabetic patients. To study the prevalence and associates of asymptomatic bacteriuria (ASB) in women with type 2 diabetes mellitus in the Iranian population, this study was conducted.

Methods

Between February 10, 2004 and October 15, 2004; 202 nonpregnant diabetic (type 2) women (range: 31 to 78 years old) with no abnormalities of the urinary tract system were included in this clinic based study. We defined ASB as the presence of at least 10⁵ colony-forming units/ml of 1 or 2 bacterial species, in two separated cultures of clean-voided midstream urine. All the participants were free from any symptoms of urinary tract infection (UTI). Associates for developing bacteriuria was assessed and compared in participants with and without bacteriuria.

Results

In this study, the prevalence of ASB was 10.9% among diabetic women. E. coli was the most prevalent microorganism responsible for positive urine culture. Most of the isolated microorganisms were resistant to Co-trimoxazole, Nalidixic acid and Ciprofloxacin. Pyuria (P < 0.001) and glucosuria (P < 0.05) had a meaningful relationship with bacteriuria but no association was evident between age (P < 0.45), duration of diabetes (P < 0.09), macroalbuminuria (P < 0.10) and HbA_1c level (P < 0.75), and the presence of ASB.

Conclusion

The prevalence of ASB is higher in women with type 2 diabetes, for which pyuria and glucosuria can be considered as associates. Routine urine culture can be recommended for diabetic women even when there is no urinary symptom.

[Risk factors for the development and persistence of asymptomatic bacteriuria in patients with type 2 diabetes]

BACKGROUND AND OBJECTIVE

To study the risk factors for the development and persistence of asymptomatic bacteriuria (AB) in type 2 diabetes mellitus (DM) patients from our health zone.

PATIENTS AND METHOD

Observational and laboratory prospective cohort study.

INCLUSION CRITERIA

women and men with type 2 DM from the 2 health centers of Petrer (Alicante).

DATA

questionnaire including particular and epidemiological data. Laboratory values: biochemistry, glycosylated hemoglobin A1C, microalbuminuria, urinary sediment and urine culture.

RESULTS

A total of 457 patients with type 2 DM were included; 63.2% women and 36.8% men. The prevalence of AB at baseline was 19.9% (25.6% in women vs 10.1% in men). 78.02% had persistence of AB after the twelve months of follow-up; 21.7% developed symptomatic urinary tract infection (UTI) and 35.2% were treated with antimicrobial agents for any reason different from UTI during the follow-up period. The persistence of AB at the end of the study was 15.5%. Female sex (p = 0.04), leukocyturia (p = 0.008), urinary incontinence (p = 0.04) and elevated C reactive protein concentration (p = 0.009) remained significant risk factors for the presence and the persistence of AB when the multivariate logistical regression analysis was done. The presence of UTI within one year before the study started (p= 0.024) and previous antibiotic treatments (p = 0.04) were also independent significant factors associated with persistent AB. 84.5% of diabetic patients with persistent AB had the same infective organism in the urine culture as those found during the initial AB.

CONCLUSIONS

In patients with type 2 diabetes, female sex, urinary incontinence, leukocyturia, and elevated C reactive protein concentration were associated with development of AB. The same occurred with obesity in women and prostatic syndrome in men. The persistence of AB with the same species of isolated microorganisms as those found in AB at study entry is frequent, but it remains to be known if eradication of pathogens is more difficult in diabetic patients or, alternatively, if AB episodes are transient.

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).

Asymptomatic bacteriuria in women with diabetes: influence of metabolic control

We screened 228 women with diabetes for bacteriuria during the period of January 1997 through December 2000 at Pisa General Hospital (Pisa, Italy). A control group of 146 women without diabetes was also evaluated. The frequency of significant bacteriuria was 17.5% (40 of 228) among women with diabetes and 18.5% (27 of 146) among women in the control group. Seven (13.5%) of 52 and 33 (18.8%) of 176 women with type 1 and in type 2 diabetes, respectively, had significant bacteriuria. The presence of higher glycated hemoglobin levels was the only significant risk factor for significant bacteriuria in women with type 2 diabetes. A similar frequency of bacteriuria in women with and women without diabetes was found. Severe impairment of metabolic control of type 2 diabetes increases the risk of acquiring asymptomatic bacteriuria.

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

OBJECTIVE

To examine whether the presence of diabetes alters the risk of acute urinary tract infection (UTI) in postmenopausal women.

RESEARCH DESIGN AND METHODS

A case-control study of the Group Health Cooperative of Puget Sound (GHC), a staff-model nonprofit health maintenance organization in Washington State, was conducted. Subjects were women aged 55-75 years who had been members of GHC for at least 1 year and who had had an acute symptomatic UTI within the preceding month. Laboratory files were used to identify women with a urine culture that grew > or =10(5) colonies of a urinary pathogen. Medical records were reviewed to confirm the presence of acute, clinically symptomatic UTI. Control subjects were randomly selected from the GHC enrollment file, screened to remove women with recent UTI, and frequency matched to cases by age within 2 years. An interviewer ascertained self-reported clinician-diagnosed diabetes. Diagnosis of diabetes was confirmed by the GHC diabetes registry. A subsample of women underwent measurement of postvoid residual bladder volume (n = 748) and culture of vaginal flora (n = 454).

RESULTS

Of the 901 case and 913 control subjects, diabetes was reported in 13.1 and 6.8%, respectively. The health plan diabetes registry confirmed the diagnosis in 92% of women who self-reported the condition. The age-adjusted odds ratio (OR) for UTI in relation to self-reported clinician-diagnosed diabetes was 2.2 (95% CI 1.6-3.0). Adjustment for frequency of sexual intercourse and history of UTI had little effect on this estimate. Compared with nondiabetic women, higher UTI odds were seen in subjects who used oral hypoglycemic agents (OR 2.9 [95% CI 1.7-5.1]) and insulin (2.6 [1.5-4.6]) but not in subjects with untreated diabetes or diabetes treated by lifestyle changes (1.3 [0.7-2.3]). No significant difference was seen in the OR for UTI in diabetic women with disease of shorter duration (<10 years, OR 1.9) or longer duration (> or =10 years, OR 2.6) or in relation to HbA(1c) level. Similar microbiologic pathogens were seen in diabetic and nondiabetic women. No significant differences were seen by diabetes status in mean postvoid residual bladder volume or vaginal flora.

CONCLUSIONS

Diabetes under pharmacologic treatment is associated with increased risk of clinically apparent UTI in postmenopausal women.

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.

Asymptomatic pyuria in diabetic women

The aim of the present study was to determine the prevalence of and the host factors for asymptomatic pyuria (ASP) in women with type 2 diabetes. The study included 179 type 2 diabetic women and consecutive 455 non-diabetic women attending as out-patients in 1996. Patients with symptoms of a urinary tract infection were excluded. ASP was defined as the presence of more than 10 leukocytes/high-power field in a random urine sample. Diabetic women more often had ASP than non-diabetic women (27.9 vs. 15.8%, P<0.001). The prevalence of ASP was significantly increased in patients with a duration of diabetes exceeding 15 years (0 approximately 4 years; 20.3%, 5 approximately 9 years; 24.3%, 10 approximately 14 years; 23.8%, and > or =15 years; 46.3%). No differences were evident in HbA(1C) between diabetic patients without ASP and those with ASP. Diabetic women with ASP more often had diabetic retinopathy, neuropathy, nephropathy, cerebrovascular disease, ischemic heart disease, and hyperlipidemia than those without ASP. However, no statistically significant differences were evident in the prevalence of hypertension, constipation, or dementia. As the degree of neuropathy increases, it is accompanied by an increasing prevalence of ASP (none, 21.4%; blunt tendon reflexes, 24.5%; symptomatic, 50.0%; and gangrene, 66.6%). The prevalence of ASP was significantly increased in the patients with proliferative diabetic retinopathy (none, 23.2%; background, 29.4%; pre-proliferative, 18.2%; and proliferative, 50.0%). As the degree of nephropathy increases, it is accompanied by an increasing prevalence of ASP (none, 20.0%; microalbuminuria, 31.9%; macroalbuminuria, 37.0%; and renal failure, 60.0%). Thus, the prevalence of ASP is increased in women with diabetes and increased with longer duration of diabetes but was not affected by glucose control. The incidence of ASP increases significantly as diabetic microangiopathy becomes severer.

Diagnosis and management of urinary tract infection in adults

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