Albumin Excretion Rate Is Not Affected by Asymptomatic Urinary Tract Infection

Abstract

OBJECTIVE—The aim of the study was to evaluate whether asymptomatic urinary tract infection (UTI) significantly influences the level of albumin excretion rate (AER) in diabetic patients. RESEARCH DESIGN AND METHODS—We screened prospectively for UTI and AER in 765 type 2 diabetic subjects. AER was determined before and after antimicrobial therapy in those patients in whom an asymptomatic UTI was diagnosed (n = 59). To interpret the clinical significance of AER changes, the coefficient of biological variation (CVb) of the AER (CVb-AER) was assessed in a control group of type 2 diabetic patients without UTI (n = 56). RESULTS—AER did not change after antimicrobial treatment either in the whole group of patients with UTI (pre: 13.8 μg/min [0.1–195] vs. post: 8.5 μg/min [0.1–185]; P = 0.1) or in those patients in whom the infection was eradicated (pre: 11.7 μg/min [0.1–195] vs. post: 7.1 μg/min [0.1–185]; NS). The CVb-AER was 64% in the control group and was inversely correlated with AER (r = −0.44; P = 0.001). The decrease of AER after antimicrobial therapy (55%) did not exceed the biological variation of AER (64%). Finally, UTI did not significantly influence the classification of diabetic patients as normo- or microalbuminuric. CONCLUSIONS—Asymptomatic UTI does not increase AER in type 2 diabetic patients. Therefore, our results suggest that testing for UTI is not necessary when AER is measured in diabetic patients.

Albuminuria Is Not Associated with Bacteriuria in Patients with Type 2 Diabetes Mellitus: A Meta-Analysis of Observational Studies

“…Considering the importance of microalbuminuria screening for diabetes care, this observation is even more relevant. In fact, we had previously demonstrated that the treatment of bacteriuria did not significantly change urinary albumin values in patients with diabetes [6], as also suggested by others [7]. …”

“…However, the small number of studies with the same albuminuria techniques precludes an adequate evaluation. Another potential issue to take into account is that when the study by Hernandez and Simo [7] was excluded from analysis, the lack of the association of micro- and macroalbuminuria was gone and a lower heterogeneity was found. Nevertheless, we should acknowledge that no peculiarity (characteristics of the patients, measurements methods, blood pressure levels, etc.)…”

“…Performing a sensitivity analysis that excludes each study at a time, the lack of association of micro- or macroalbuminuria with bacteriuria was not maintained, with the exception of the study by Hernandez and Simo [7]; the OR for bacteriuria was 1.89 (95% CI: 1.27–2.79, I 2 = 36%).…”

“…Regarding symptoms, five studies evaluated only asymptomatic bacteriuria [4,5,7,11,12], one study evaluated asymptomatic plus symptomatic [6], and one study did not report frequency of symptoms [13]. The chance for microalbuminuria or macroalbuminuria was not increased by the presence of bacteriuria in a sensitivity analysis including only studies that evaluated asymptomatic bacteriuria (OR: 1.71, 95% CI: 0.89–3.30, I 2 = 71.7%).…”

“…However, the possible association between bacteriuria and increased urinary albumin is controversial. Some cross-sectional studies observed an increased prevalence of macroalbuminuria and/or microalbuminuria in patients with bacteriuria [4,5], while other studies do not support this observation [6,7]. The aim of the present study was to investigate the association of albuminuria and bacteriuria in patients with type 2 diabetes by a systematic review and meta-analysis of observational studies.…”