Significant bacteriuria in outpatient diabetic and non-diabetic persons.

OBJECTIVE

The prevalence of significant bacteriuria (SB) in diabetes mellitus has not been clearly established. Having previously investigated SB frequency in inpatient diabetic women, we now screened for SB (both asymptomatic and symptomatic forms) in outpatients.

METHODS

We examined 511 consecutive outpatients with Type 1 (T1D) or Type 2 diabetes (T2D), and 98 non-diabetic subjects. At least one uncontaminated midstream urine sample was available from 602 subjects: 64 T1D (37 female, age 49 +/- 13 years, diabetes duration 23 +/- 15 years), 441 T2D (212 female, 66 +/- 10 years, 12 +/- 10 years), and 97 healthy control subjects (39 female, 57 +/- 12 years). On the same day, we determined: blood cell count, fasting plasma glucose (FPG), glycated haemoglobin (HbA(1c)), plasma creatinine, urinary creatinine, and urinary albumin excretion (UAE; microg/mg urinary creatinine).

RESULTS

The rate of SB was 14.1% in T1D, 9.3% in T2D and 6.2% in control subjects (P = NS). The 50 diabetic patients with SB differed from the 455 diabetic patients without SB in gender (43 male vs. 206 female, P < 0.001), FPG (10.2 +/- 3.6 vs. 9.2 +/- 2.9 mmol/l, P < 0.05), HbA(1c) (7.8 +/- 1.1 vs. 7.5 +/- 1.3%, P < 0.05), and UAE (median 15.6 vs. 7.6 microg/mg, P < 0.01). Eleven diabetic patients with SB had symptoms (vs. 48 without SB, P < 0.05); UAE levels were higher in the 39 asymptomatic diabetic patients with SB than in the 11 symptomatic patients.

CONCLUSIONS

The prevalence of SB is similar in outpatient diabetic individuals and in non-diabetic subjects. The main risk factors for SB in diabetic patients were female gender and UAE. The likelihood of asymptomatic SB increased with UAE levels, i.e. with the presence of established microangiopathy. Poor glycaemic control is associated with bacteriuria, either as a cause or consequence of bacteriuria.