Hallucinations in Elderly Women with UTI: Timeline for Resolution

Critical Evidence Against Antibiotic Benefit for Delirium/Hallucinations

The Infectious Diseases Society of America (IDSA) guidelines provide the strongest evidence that treating bacteriuria does not improve mental status changes in elderly patients, with no significant functional recovery in delirious elderly patients (≥70 years) treated for asymptomatic bacteriuria (ASB) compared to untreated patients (unadjusted RR, 1.10 [95% CI, .86–1.41]) 2
Delirious patients treated for ASB actually had poorer functional outcomes compared to non-delirious ASB patients who were not treated (adjusted OR, 3.45 [95% CI, 1.27–9.38]) 2
Treatment of ASB in patients with delirium has not been shown to reduce severity or duration of delirium, according to the IDSA guidelines 1, 2
Delirium tends to have a naturally fluctuating course independent of antibiotic treatment, as stated by the IDSA 2

The IDSA recommends determining if a patient has a true UTI or asymptomatic bacteriuria by looking for fever, dysuria, urgency, frequency, suprapubic pain, or costovertebral angle tenderness, and if these classic UTI symptoms are absent, it is likely ASB, not UTI 1, 2, 3, 4
If a patient has ASB, the IDSA guidelines advise against treating with antibiotics for the hallucinations/delirium, and instead recommend evaluating for dehydration, medication effects, metabolic disturbances, hypoxia, and other causes of delirium 1, 2, 4
The IDSA guidelines also state that if a patient has a true UTI with systemic signs (fever, sepsis), they should be treated with appropriate antibiotics, but mental status should be monitored and rapid improvement in hallucinations should not be expected from antibiotics alone 1, 2

The IDSA guidelines emphasize that current evidence does not suggest a causal relationship between bacteriuria and mental status changes, and treating ASB in confused elderly patients increases harm without benefit 1, 2
The IDSA guidelines also note that the specificity of urine dipstick tests is only 20-70% in elderly patients, making overdiagnosis common, and that mental status changes in elderly patients require broad differential diagnosis, not reflexive antibiotic treatment 3, 4