Medical case narrative
Delirium in an 83-year-old — a UTI story, told carefully
What happened
An 83-year-old woman became acutely confused — delirium — and a urine culture grew more than 10⁵ CFU of E. coli sensitive to fluoroquinolone antibiotics.
What it looked like
Sudden confusion in an older adult, the presentation families describe as "she was herself yesterday."
What the labs found
A significant urine culture alongside the delirium.
What changed
On levofloxacin 250 mg/day for ten days, her confusion resolved during treatment, and within 48 hours her appetite had returned and her ability to perform daily activities was back to normal, per the case write-up.
The honest complication — and why this entry carries it
This case is a vignette inside a review article, not a standalone case report, and the causation is genuinely contested: a 2022 record review (PMC9706880) found no difference in day-7 delirium with antibiotics (RR 0.94), and IDSA/AAFP guidance advises assessing other causes first and not treating bacteria found in urine, without urinary symptoms, for delirium alone. The story is real as an experience; the mechanism lesson is "look for causes of delirium, including infection — and keep looking," not "every confused elder needs an antibiotic."
The test that told the story
Urinalysis and urine culture — as one part of a full delirium workup.
Sources: Patient Care Online case vignette; PMC9706880 (2022) and IDSA/AAFP guidance as contesting sources.