Urinary Tract Infections

Leading cause of morbidity and health care expenditures in persons of all ages.

An estimated 50 % of women report having had a UTI at some point in their lives.

8.3 million office visits and more than 1 million hospitalizations, for an overall annual cost > $1 billion.

Peter Ulleryd, Sahlgrenska University Hospital, Göteborg, Sweden

Virulence Host factors

Infection No infection

UTIs may occur either because ofthe pathogenicity of the organism,the susceptibility of the host or a

combination of both factors

Virulence factors of the gram-negative uropathogens E. coli and P. mirabilis

Host defenses Host defenses Antibacterial properties of urineAntibacterial properties of urine• Osmolality (extremes of

high or low osmolalities inhibit bacterial growth)

• High urea concentration• High organic acid

concentration• pH

AntiAnti--adherence mechanismsadherence mechanisms• Bacterial interference

(naturally endogenous bacteria in the urethra, vagina, and periurethral region)

• Urinary oligosaccharides (have the potential to detach epithelial-bound E.coli

• Tamm-Horsfall protein (uromucoid): coating of E.coli by this protein might prevent attachment

MiscellaneousMiscellaneous• Mucopolysaccharide lining of the bladder• Urinary immunoglobulins• Spontaneous exfoliation of uroepithelial cells with bacterial

detachment• Mechanical flushing of micturition

Urinary Catheterization

alters these

defensive mechanisms

CatheterCatheter--Associated UTIAssociated UTI

Risk of bacteriuria is ~ 5%/day (long Risk of bacteriuria is ~ 5%/day (long term catheter bacteriuria is inevitable).term catheter bacteriuria is inevitable).40% of nosocomial infections40% of nosocomial infectionsMost common source of gramMost common source of gram--negativenegativebacteremia.bacteremia.Etiology: E.coli, Proteus, Enterococcus, Etiology: E.coli, Proteus, Enterococcus, Pseudomona, Enterobacter, Serratia, Pseudomona, Enterobacter, Serratia, CandidaCandida

Duration of cahteterizationDaily Prevalence of Acquired Bacteriuria in Patients

Receiving Bladder Drainage by Indwelling Urethral Catheters

Garibaldi et al. Factors predisposing to bacteriuria during indwelling uretheral catheterization. N Engl J Med 1974;291:215.

Risk Factors Associated with the Development of CAUTI

Increasing duration of catheterizationNot receiving system antibiotic therapyFemale sexDiabetes mellitusOlder ageRapidly fatal underlying diseasesNonsurgical diseasesFaulty aseptic management of the indwelling catheterBacterial colonization of drainage bagAzotemia (serum creatinine concentration > 2 mg/dlCatheter not connected to a urine meterPeriurethral colonization with uropathogens

Asymptomatic Bacteriuria

• The best way to avoid having patients develop IUC-related UTIs is to avoid initial catheter insertion or to minimize the duration of catheter use.

• UTIs are the tenth most likely reason for a Medicare patient to have an unplanned readmission to the hospital

Lee EA Perm J 2011

CA-UTI reduction initiatives began in late

2007 by creation of a catheter

management and removal policy:

• nurse and care partner education

• check off on sterile technique

• insertion competency

• strict guidelines on catheter and perineal

skin care

• mandatory removal of the urinary catheter

at 5 days unless a counter-order was

written.

Community-Acquired UTI

E. coli

K.pneumoniae

Proteus

S.saprophyticus

S.epidermidis &gram neg enterics

Enterococcus

Nosocomial UTIcatheter associated

Short Term Long TermE.coli

E.coli

Pseudomonas Pseudomonas

Proteus

Proteus

Enterobacter

Candida

ProvidenciaMorganella

S.aureus

Enterococcus

FQ resistance

With time

By patient age

By patient sex

Smithson A EJCMID 2011

Prevalence (%) of ESBL producing isolates by species in Assistance Publique Hopitaux de Paris long-term-care facilities

(2001–2005).

Nicolas-Chanoine et al. CMI 2008

Risk factors for ESBL-producing Escherichia coli and Klebsiella pneumoniae

Mendelson et al EJCMID 2005

Multivariate logistic regression analyses:

• Fluoroquinolone use days: OR 1.33 (1.04–1.69) P=0.02

• History of UTI: OR 2.56 (1.37–4.78) P=0.003

Multidrug-Resistant Organisms in LTCF

• MDRGN were isolated more frequently than MRSA or VRE throughout the study period.

• More than 80% of MDRGN isolates were resistant to ciprofloxacin, TMP/SMX, and ampicillin/sulbactam.

• Resistance to three, four, or more antimicrobials were identified among 122 (67.8%), 47 (26.1%), and 11 (6.1%) MDRGN isolates, respectively.

O’Fallon J Gerontol. 2009

Acquisition of Multidrug-Resistant Gram-Negative Bacteria within a LTCF Population

O’Fallon E et al ICHE 2010

• There were significantly higher antibiotic costs, re-consultation costs and total costs for patients whose infections were resistant to at least one antibiotic.

IJAA 2009

Appropriateness by Site of Infection

0

10

20

30

40

50

Urinary

Respiratory

Gastrointestinal

Skin/Soft Tissue

Ear/Nose/Throat

Genital TractOther

AppropriateInappropriate

p=0.76

Lautenbach, Arch Intern Med 2003;163:601

What factors or conditions are likely to have determined UTI?

What measures should have been put in place to prevent it?