title: Interleukin-6 concentrations in the urine and dipstick analyses were related to bacteriuria but not symptoms in the elderly: a cross sectional study of 421 nursing home residents.
abstract: BACKGROUND
  Up to half the residents of nursing homes for the elderly have asymptomatic bacteriuria (ABU), which should not be treated with antibiotics. A complementary test to discriminate between symptomatic urinary tract infections (UTI) and ABU is needed, as diagnostic uncertainty is likely to generate significant antibiotic overtreatment. Previous studies indicate that Interleukin-6 (IL-6) in the urine might be suitable as such a test. The aim of this study was to investigate the association between laboratory findings of bacteriuria, IL-6 in the urine, dipstick urinalysis and newly onset symptoms among residents of nursing homes.
  
  
  METHODS
  In this cross sectional study, voided urine specimens for culture, urine dipstick and IL-6 analyses were collected from all residents capable of providing a voided urine sample, regardless of the presence of symptoms. Urine specimens and symptom forms were provided from 421 residents of 22 nursing homes. The following new or increased nonspecific symptoms occurring during the previous month were registered; fatigue, restlessness, confusion, aggressiveness, loss of appetite, frequent falls and not being herself/himself, as well as symptoms from the urinary tract; dysuria, urinary urgency and frequency.
  
  
  RESULTS
  Recent onset of nonspecific symptoms was common among elderly residents of nursing homes (85/421). Urine cultures were positive in 32% (135/421), Escherichia coli was by far the most common bacterial finding. Residents without nonspecific symptoms had positive urine cultures as often as those with nonspecific symptoms with a duration of up to one month. Residents with positive urine cultures had higher concentrations of IL-6 in the urine (p < 0.001). However, among residents with positive urine cultures there were no differences in IL-6 concentrations or dipstick findings between those with or without nonspecific symptoms.
  
  
  CONCLUSIONS
  Nonspecific symptoms among elderly residents of nursing homes are unlikely to be caused by bacteria in the urine. This study could not establish any clinical value of using dipstick urinalysis or IL-6 in the urine to verify if bacteriuria was linked to nonspecific symptoms.
authors.affiliation: Research and Development Unit, Primary Health Care in Southern Älvsborg County, Sven Eriksonsplatsen 4, SE-503 38 Borås, Sweden. par-daniel.sundvall@vgregion.se.
authors.forename: Pär-Daniel
authors.initials: PD
authors.lastname: Sundvall
authors.forename: Marie
authors.initials: M
authors.lastname: Elm
authors.forename: Peter
authors.initials: P
authors.lastname: Ulleryd
authors.forename: Sigvard
authors.initials: S
authors.lastname: Mölstad
authors.forename: Nils
authors.initials: N
authors.lastname: Rodhe
authors.forename: Lars
authors.initials: L
authors.lastname: Jonsson
authors.forename: Bengt
authors.initials: B
authors.lastname: Andersson
authors.forename: Mirjana
authors.initials: M
authors.lastname: Hahn-Zoric
authors.forename: Ronny
authors.initials: R
authors.lastname: Gunnarsson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001437:Bacteriuria / Q000175:diagnosis* / Q000188:drug therapy / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D003430:Cross-Sectional Studies; D005260:Female; D006707:Homes for the Aged; D006801:Humans; D015850:Interleukin-6 / Q000652:urine*; D008297:Male; D009735:Nursing Homes; D013548:Sweden / Q000453:epidemiology; D016482:Urinalysis / Q000379:methods / Q000592:standards; D014552:Urinary Tract Infections / Q000175:diagnosis / Q000188:drug therapy / Q000652:urine
chemical_list: D000900:Anti-Bacterial Agents; D015415:Biomarkers; C508600:IL6 protein, human; D015850:Interleukin-6