α1-microglobulin as a marker of proximal tubular damage in urinary tract infection in children

The urinary alpha 1-microglobulin (alpha 1-M) as a marker of proximal tubular damage was measured in 86 children, aged 3/12 to 12 years, with a diagnosis of urinary tract infection (UTI) and fever. All patients had normal glomerular filtration rates (GFR). They were divided into 2 groups: A: with UTI and etiological factor E. coli, B: with UTI and etiological factor Proteus sp. Similar measurements of alpha 1-M were obtained for a control group of healthy children. An increased mean level serum alpha 1-M was observed in patients with UTI and fever compared to control group (p < 0.001). Urinary alpha 1-M as the alpha 1-microglobulin/creatinine ratio was higher in both tested group of patients: with UTI and fever. Those found in group A1 and B1 before treatment were the highest and statistically significantly elevated after treatment (group A2 and B2: p < 0.001). Our results indicate the usefulness of the urinary alpha 1-microglobulin/creatinine ratio as a marker of proximal kidney tubule damage in children with E. coli and Proteus sp. infections. Additionally, it seems to be associated with the humoral and cellular immune response.