II. Symptoms
III. Signs: Upper tract infection
- Nausea or Vomiting
- Altered Level of Consciousness
- Generalized weakness or malaise
- Flank tenderness is absent in as many as 50% of elderly patients with Pyelonephritis
IV. Risk factors
- Postmenopausal Women
- Benign Prostatic Hyperplasia (BPH)
- Neurogenic Bladder
- More common in Alzheimer's Disease, Parkinsonism and CVA history
- Diabetes Mellitus
- Prolonged bed rest
- Urinary Incontinence
- Fecal Incontinence
- Indwelling catheter
V. Causes (non-E. coli Urinary Tract Infections are more common in younger patients)
- Escherichia coli (most common)
- Proteus mirabilis
- Klebsiella
- Enterobacter
- Coagulase-negative Staphylococcus aureus
- Polymicrobial Urinary Tract Infections (especially with indwelling Urinary Catheter)
VI. Labs
- See Urinary Tract Infection
-
Urinalysis
- Negative dipstick of both Urine Nitrite and Urine Leukocyte Esterase has a Negative Predictive Value (NPV) of 88%
- However PPV Urine Nitrite or urine Leukocyte esterase Positive Predictive Value is only 51%
- Sundvall (2009) BMC Geriatr 9:32 [PubMed]
- Urine microscopy Leukocyte count >26 in women age >=65 years is a reasonable cut-off for pyuyria predicting UTI
- Negative dipstick of both Urine Nitrite and Urine Leukocyte Esterase has a Negative Predictive Value (NPV) of 88%
-
Urine Culture
- Discriminatory threshold of 100,000 colonies of growth misses Urinary Tract Infections in elderly
- Signs and symptoms of UTI in elderly women: >10,000 CFU
- Signs and symptoms of UTI in elderly men and non-E. coli: >1000 CFU
- Sundvall (2009) BMC Geriatr 9:32 [PubMed]
- Insert a fresh catheter for sample if indwelling catheter (See Urinary Catheter associated UTI)
- Otherwise Urine Culture represents the colonizing Bacteria in as much as 25% of cases
- Removal of infected catheter speeds recovery
- Discriminatory threshold of 100,000 colonies of growth misses Urinary Tract Infections in elderly
VII. Diagnosis
- See Urinary Catheter associated UTI
- See Urinary Tract Infection
- Distinguish Asymptomatic Bacteriuria from Urinary Tract Infection
- Findings suggestive of Urinary Tract Infection in the elderly (Juthani-Mehta)
- Major Criteria (required)
- Minor Criteria (requires 1)
- Change in urine character
- Altered Level of Consciousness (unreliable in Dementia, and non-specific for UTI)
- Interpretation
- None of 3 criteria present: 25% chance of bacteriuria and pyuria
- Criteria met (1 major and 1 minor): 63% chance of bacteriuria and pyuria
- References
- Findings suggestive of Urinary Tract Infection in elderly at long-term care facilities (Loeb)
- Major criteria (requires 1)
- Minor criteria (requires 1)
- New or worsening urinary urgency
- Urinary Frequency
- Suprapubic Pain
- Gross Hematuria
- Costovertebral Angle Tenderness
- Urinary Incontinence
- References
VIII. Management
- See Urinary Tract Infection for Antibiotic selection
-
Antibiotic precautions
- Nitrofurantion
- Associated with Acute Nitrofurantoin Pulmonary Toxicity
- Contraindicated in patients with Creatinine Clearance <60 ml/min
- Do not use for longterm Urinary Tract Infection prophylaxis in the elderly
- Fluoroquinolones
- Associated with Tendinopathy and tendon rupture
- Trimethoprim-Sulfamethoxazole (TMP-SMZ, Septra, Bactrim)
- Increased Antibiotic Resistance in Urinary Tract Infections
- Reasonable Antibiotic selection in communities where resistance rates are <20%
- Contraindicated where Creatinine Clearance <15 ml/min
- Nitrofurantion
- Extended Antibiotic regimen duration is typical in elderly
- Duration: 7 day course
- Standard Antibiotic course in elderly women (extended from typical 3 day Antibiotic course)
- Duration 10 day course
- Duration: 7 day course
-
Asymptomatic Bacteriuria
- Common in elderly (10-20%) and especially catheterized patients (up to 10% colonization rate per day while catheterized)
- Standard treatment indications
- Pending urologic procedures
- Diabetes Mellitus
- Spinal cord injuries (e.g. Quadriplegia)
- Precautions
- Many elderly patients are asymptomatic with UTIs despite exam markers of systematic infection (e.g. fever, Hypotension)
- Treatment of Asymptomatic Bacteriuria is reasonable in the elderly per clinical judgement (using criteria above)
- Overdiagnosis of UTI in elderly is common
- Misdiagnosis rate of UTI in hospitalized elderly patients: 40%
- Do not automatically attribute Altered Level of Consciousness to an abnormal Urinalysis in the elderly
- See Infections in Older Adults
- Start with broad evaluation and management per Sepsis protocol
- Consider other serious infections (e.g. Meningitis) and other Altered Level of Consciousness Causes
- Many elderly patients are asymptomatic with UTIs despite exam markers of systematic infection (e.g. fever, Hypotension)
IX. Prognosis
- Mortality for UTI with bacteremia in the elderly: 5% at 28 days
X. Prevention
XI. References
- Khoujah (2013) Crit Dec Emerg Med 27(4): 12-21
- Staykova (2013) Nephrology 4(1): WMC003968
- Beveridge (2011) Clin Interv Aging 6: 173-80 [PubMed]