Urinary tract infection in the

elderly

Aurora Pop-Vicas, MD, MPH

Infectious Diseases

Memorial Hospital of RI

Brown University

Outline

• Asymptomatic bacteriuria • Pathogenesis

• Diagnosis

• Treatment

• Urinary tract infection • Diagnosis

• Treatment

• Prevention

Asymptomatic bacteriuria

Definition

• Asymptomatic bacteriuria

• > 105 cfu uropathogenic bacteria (CDC)

» Regardless of indwelling catheters or not

• > 102 cfu single organism

» When urine obtained by fresh catheterization

OR

» By bladder puncture (IDSA)

» NOT applicable for chronic indwelling catheters

• No fever > 38°C, suprapubic or CVA tenderness

Definition

• Women: • Same bacterial strain

• 2 consecutive clean-catch voided specimens

• ≥ 105 cfu/mL

• Men • Single clean-catch voided specimen

• ≥ 105 cfu/mL

Pathogenesis

• Host determinants

– Women: • Prior history of UTI in earlier age

• Less vaginal lactobacilli higher pH increased colonization with uropathogenic strains

• Impaired voiding (i.e. cystocele, bladder diverticuli)

– Men: • Prostate hypertrophy urethral

obstruction/turbulent urine flow bacterial ascension into the bladder

• Increased post-void urine residual volume

Pathogenesis

Nature Reviews - Microbiology

Prevalence of asymptomatic bacteriuria

Category Percent

Young women 1-2%

Women age 65 – 90 6-16%

Women ≥ 90 22 – 43%

Men ≥ 65 5-21%

Women in LTCF 25 -50%

Men in LTCF 15-35%

Juthani-Mehta, Clin Geriatr Med 23 (2007): 585

Asymptomatic bacteriuria

• Often associated with pyuria • Especially in LTCF residents

• Virtually universal in patients with

indwelling catheters

Nicolle LE. Infect Control Hosp Epidemiol 2001;22:167–75.

Warren JW, Tenney JH, Hoopes JM, et al. J Infect Dis 1982;146:719–23.

Most common bacterial species

Category Bacterial species

Most common E. coli

Community-dwelling elderly E. Coli

Staph coagulase-negative

NH residents Proteus mirabilis

Providencia stuarti

Klebsiella pneumoniae

Chronic catheters (biofilms) Proteus mirabilis

Providencia stuarti

Pseudomonas aeruginosa

Prognosis

• Progression to bacteremia is rare • Prospective study of 1497 patients with urinary

catheters

• Bacteriuria: 15%

• Bacteremia: 0.3% (4 patients)

Archives Internal Medicine, March 13 (160), 2000

Asymptomatic bacteriuria – Treatment not

recommended

Asymptomatic bacteriuria – Treatment not

reccomended

Asymptomatic bacteriuria

• Treatment recommended: • Pregnant women

• Patients prior to urologic procedures where

mucosal bleeding is anticipated

• Patients prior to TURP

Urinary Tract Infection

Infectious disease hospitalizations among

elderly in US

234

78.761.7

39.1

0

50

100

150

200

250

Rate

per

10,0

00 a

du

lts

LRT UTI Septicemia Cellulitis

ARCH INTERN MED/VOL 165, NOV 28, 2005

Study period: 2000-2002

UTI - Epidemiology

UTI – Chronic indwelling catheters

• Chronic indwelling catheters • Bacteriuria universal

• More likely to develop infection

• More likely to have fever from a urinary source,

bacteremia, and pyelonephritis

• Increased mortality likely due to poorer functional

status and more comorbidities

UTI - Prevention

• Options for prevention of recurrent UTIs: • Intravaginal estriol for postmenopausal women?

• Antibiotic prophylaxis

– If ≥ 2 symptomatic UTIs over 6 months

– Agents used: Bactrim, Keflex, Macrobid

• Factors that increase risk of recurrent UTIs • History of UTI at younger age

• Incontinence

• Cystocele

• Postvoid residual urine

• Poor functional status, NH residence, catheterization

• Severe BPH

UTI - Diagnosis

• Diagnosis:

– Ambulatory, outpatient elderly:

• Bacteriuria ≥105 cfu/mL PLUS genito-urinary symptoms

• Cystitis: dysuria, frequency, urgency, nocturia, suprapubic

discomfort, occasional hematuria

• Pyelonephritis: CVA pain, fever, and variable GU symptoms

– Institutionalized elderly adults with cognitive

impairment

• Difficult to distinguish asymptomatic bacteriuria from UTI

• Laboratory criteria plus symptoms

• ? Which symptoms?

Urinary Symptoms

Incontinence

Frequency

Urgency

Suprapubic pain

Flank pain

Fever

Lack of well-being symptoms

Anorexia

Difficulty in falling asleep

Difficulty in staying asleep

Fatigue

Malaise

Weakness

No difference found in the prevalence of these symptoms during

periods of bacteriuria versus nonbacteriuria in the elderly

Boscia JA, KobasaWD, Abrutyn E, et al. Am J Med 1986;81:979–82.

UTI in NH residents - definition

• The McGeer criteria:

– If no indwelling catheter, 3 or more of:

• fever ≥ 100.4°F

• new or increased burning on urination, frequency,

or urgency;

• new flank or suprapubic pain or tenderness;

• change in character of urine;

• worsening of mental or functional status.

– If indwelling catheter, 2 or more

McGeer A, Campbell B, Emori TG, et al.. Am J Infect Control 1991;19:1–7.

UTI in NH residents - diagnosis

• The Loeb criteria

– NH residents without catheters:

• Acute dysuria OR fever (≥ 100°F) plus 1 or more:

– New or worsening urgency or frequency

– Suprapubic pain

– Hematuria

– CVA tenderness

– Urinary incontinence

Infect Control Hosp Epidemiol 2001;22:120–124

UTI - Diagnosis

UTI - Microbiology

Category Bacterial species

Outpatient elderly

(UTI with

bacteremia)

GNR (E coli, etc): 80%

GPR (Enterococcus, S. aureus): 20%

NH residents E coli

P. Aeruginosa

VRE

Candida

Other GNR

Treatment

UTI - Treatment

• Duration – Outpatient women – acute cystitis:

• FQ – 3 days as effective as 7 days

• TMP – SMX – 3 days

• Nitrofurantoin – 5 days

– Outpatient men – acute cystitis • 7 days

– Outpatient men – recurrent cystits – chronic bacterial prostatitis

• 6 -12 weeks

– Pyelonephritis – men and women • 10-14 days

Figure 1. Patterns of empiric antimicrobial use at

hospital admission among patients with community-

onset Clostridium difficile infections

Pop-Vicas et al, SHEA 2011 abstract

N = 88 patients

Characteristic Cases (N = 30)

N (%)

Controls (N = 58)

N (%)

Odds Ratio

P value

Age ≥ 80 years 16 (53) 16 (28) 3 (1.1 – 8.3) 0.017

NH residence 17 (57) 15 (26) 3.8 (1.3 – 10.5) 0.004

Nonverbal on admission 10 (33) 3 (5) 9.2 (2.0 – 55.4) < 0.005

Dementia 7 (23) 4 (7) 4.1 (0.9 – 20.7) 0.027

Suspected UTI 12 (40) 6 (10) 5.8 (1.7 – 21.2) 0.001

Acute renal failure 13 (43) 8 (14) 4.8 (1.5 – 15.5) 0.002

Severe CDI 23 (77) 29 (50) 3.2 (1.1 – 10.4) 0.016

Table 1. Risk factors for injudicious antimicrobial use at hospital admission

among patients with community-onset CDI (univariate analysis)

Risk factor Adjusted Odds Ratio ( 95% Confidence Interval)

P value

Suspected UTI 7.0 (2.0 – 23.7) 0.002

Acute renal failure 4.5 (1.5 – 13.7) 0.009

Severe CDI 3.2 (1.0 – 10.3) 0.046

Independent risk factors associated with injudicious antimicrobial use at

hospital admission for patients with community-onset CDI

Judicious antimicrobial use