How do pediatric and geriatric presentations of urinary tract infections (UTIs) differ?

Pediatric vs Geriatric UTI Presentations: Key Differences

Children with UTI typically present with fever as the dominant feature (especially under age 2), while geriatric patients often present with atypical symptoms like confusion and functional decline rather than classic urinary symptoms.

Pediatric Presentation (Especially <2 Years)

Clinical Features

• Fever is the predominant and often only presenting sign in preverbal children, making UTI a critical consideration in any unexplained fever 1
• Nonspecific symptoms predominate in infants and young children, including irritability, poor feeding, vomiting, and failure to thrive 2
• Older children may present with more classic symptoms: dysuria, urinary frequency, hematuria, abdominal pain, back pain, or new daytime incontinence 1
• Pediatric UTI should be considered complicated until proven otherwise due to the risk of underlying anatomic or functional abnormalities 2

Diagnostic Approach

• Requires invasive specimen collection (catheterization or suprapubic aspirate) in non-toilet-trained children to ensure accurate diagnosis 1
• Bagged urine samples are inadequate for culture and should not be used 1
• All children <2 years require imaging after first febrile UTI (renal/bladder ultrasound) to identify significant renal abnormalities 1

Microbiology

• Enterococcus faecium dominates in newborns (45%), then shifts to E. coli predominance in older pediatric patients (34%) 3
• The pathogen spectrum is narrower compared to geriatric patients 2

Geriatric Presentation (>65 Years)

Clinical Features

• Confusion and functional decline are often more prominent than classic urinary symptoms, making diagnosis challenging 4
• Classic urinary symptoms (dysuria, frequency, urgency) may be absent or overshadowed by altered mental status 4
• Fever may be present but is not a reliable indicator, and urine testing should not be automatic in febrile geriatric patients without specific urinary symptoms 5
• Baseline presence of asymptomatic bacteriuria (up to 30% in women ≥85 years) complicates diagnosis 4, 2

Diagnostic Challenges

• Urine dipstick tests have limited specificity (20-70%) in elderly patients, and negative results do not reliably exclude UTI when symptoms are present 4, 6
• Comorbidities (41.4% with urological diseases, 20.7% with diabetes, 19.2% with neurological diseases) complicate the clinical picture 7
• History of catheterization (17.1%), prior UTI (27.9%), and recent hospitalization (29.3%) are common confounding factors 7

Microbiology

• Broader spectrum of organisms including more gram-positive pathogens compared to younger adults 2
• E. coli remains most common (40%) but with higher rates of Klebsiella pneumoniae, Enterococcus species, and Pseudomonas aeruginosa 3
• Multidrug resistance increases significantly with age and is most serious in geriatric patients 3
• Higher resistance rates to cephalosporins, carbapenems, and fluoroquinolones in geriatric isolates 3

Treatment Implications

Pediatric Management

• Parenteral broad-spectrum antimicrobials for acutely ill children 2
• Oral therapy (7-10 days) acceptable for less ill children using TMP-SMX, beta-lactams, or cephalosporins 2, 1
• Treatment within 48 hours of fever onset reduces risk of renal scarring 8

Geriatric Management

• Conservative approach with longer treatment durations (7 days minimum) covering broad spectrum of uropathogens 2
• Fosfomycin (3g single dose) is excellent first-line choice due to low resistance rates and safety in renal impairment 4, 6
• Fluoroquinolones for 7 days are preferred empiric approach when appropriate, but avoid if used in last 6 months 6, 2
• Mean hospitalization duration of 7.6 days with 5% mortality rate underscores severity 7

Critical Pitfalls to Avoid

• In children: Missing UTI diagnosis in febrile infants without obvious source; using bagged specimens for culture; failing to image children <2 years after first febrile UTI 1
• In geriatrics: Automatically testing/treating fever without urinary symptoms; dismissing UTI based on negative dipstick alone when symptoms present; treating asymptomatic bacteriuria; using fluoroquinolones as routine first-line 5, 4, 6