Urinary diversion and UTI:

Adaptation of epithelial response

Rob Pickard

Professor of Urology

Newcastle Universityr.s.pickard@ncl.ac.uk

My Talk

• Epithelial – Bacterial interactions

– Tolerance versus immune response

• Ileal conduit – a surgically-fashioned

epithelial paradox

• The clinical problem

• The laboratory investigation

• The clinical application

• Summary

Bacteria – Epithelium Interaction

Urinary Tract

Maintain sterility

•Surveillance

•Seek & destroy

•Immune response

•Innate

•Encourages virulence

GI – Tract

Symbiotic relationship

•Control

•Tolerance

•Arm’s length

•Discourage virulence

Ureter

Ileum

Escherichia coli (E. coli)

Bacterial adaption

The changing face of E. coli

• Planktonic– ‘Floaters’ Asymptomatic bacteriuria

(ABU)

• Motile– Flagellin

• Invasive – Uropathogenic E. coli(UPEC)– Adhesion molecules

• Adhesins

• Pili

– Membrane digestion

• Hyalurinidase

Changin

g g

enoty

pe

Urinary surveillance

• Fluid flow – 5 ml/min

• pH < 7

• Antimicrobials– Proteins

• Tamm Horsfall

• Lipocalin

• Lactoferrin

– Peptides• Cathelicidin (LL-37)

• Alpha defensins (HD5)

• Beta defensins (BD1)

Epithelial Response

• Cell surface receptors

– Pathogen Recognition Receptors

• TLRs 4- LPS; 5 - flagellin

• Signal Transduction

– NFκB

– NOD2

• Transcription

• Effectors

– Anti-microbial peptides (AMP)

– Anti-microbial proteins

– Cytokines

Toll - Like receptor 4

Adapter molecules

Intermediaries

NF B

Activation

Cell Nucleus

leading to AMP secretion

Inside

cell

Outside

cell

ABU

UPEC

+Transcription factors gene (DNA) mRNA functional peptide

Ileal conduit – epithelial paradoxJoining the

bacterially–tolerant

ileal mucosa to the

Immune-active ureteric

mucosa

Constant bacterial threat

•Ileum

•Skin

What does the conduit do:

•Seek and destroy?

•Or tolerate?

The Clinical Question

Why do some people with

a urostomy get lots of

urinary infections and

others don’t?

Defining a urinary infection (CDC)

Symptomatic UTI

• Collection of symptoms– ‘Flu-like’ feelings

– Fever

– Rigors

– Loin pain

• > 104/ml of 1 or 2 organisms in catheterised specimen of urine

Asymptomatic bacteriuria

• > 104/ml of 1 or 2 organisms in catheterised specimen of urine

• No symptoms

• May have changes in urine– Cloudy

– Smelly

– Mucus ↑

UTIs – some are worse than

others!

• Simple– Local symptoms

– Get better quickly

– May not need antibiotics

• Fever/shivers– Toxaemia

– Need antibiotics

• Bacteraemia– Need IV antibiotics in

hospital

Symptomatic UTIs – How common

are they in people with urostomy?

•c80% have bacteriuria

•Symptomatic recurrent UTIs are common 20 -30%

•The problem continues over many years

Are recurrent UTIs important?

Antibiotics don’t help much

& cause problems

Loss of functioning renal tissue

Costs: Personal and health care

Miserable

The Paradox

0

25

50

75

100

Bugs

in

urine

% People withurostomy

0

25

50

75

100

Infection

% People withurostomy

Is it the person or the bug?

What may keep bacteria at bay?

Anti-microbial peptides (AMPs)

• Small protein molecules (15 – 30 ααs)– Highly conserved

– Made by epithelia

• Constitutively

• Induced

– Bacteriocidal

• +ve charged segment – hydrophilic

• Non-charged segment – lipophilic

– defensins

– defensins

– Cathelicidin

Our Research 8/07 – 12/09

Aims

1. Are the AMPs present

and active in ileal

conduits?

2. Do people with

urostomies who get

recurrent symptomatic

UTIs have reduced

amounts or activity of

AMPs?

1. 10 People undergoing

ileal conduit surgery

2. 20 people with a conduit

and no infections

3. 20 people with a conduit

and > 2 UTIs per year

Stoma clinic Freeman Hospital FMS Newcastle University

Participants

Our Participants

17 people had recurrent UTIs –average

Of 7 per year ( ) and 17 none ( )People with recurrent UTIs ( ) reported

had worse health than those without ( )

1. Results – id of AMPs

RNA level

Protein level

HD5 - ileum BD1 - ureter HD5 - ureter

Ileum

Ureter*

*

Results - details

- defensin – BD1

- defensin – HD-5

A new discovery – HD5 in the urinary tract - an exciting development!

Only 2 AMPs were consistently constitutively expressed in both ureter and ileum

18S RNA control

2. Change in AMP expression after

diversion

3. rUTIs versus asymptomatic A. No difference in urinary activity against

standard organism.

B. Organisms isolated from

rUTI more virulent

C. High urinary activity against infecting

organism in rUTI group

D. High urinary activity in rUTI group

against highly virulent UPEC strain

Our Conclusions• Asymptomatic patients

– Adaptation of ureteral urothelium to a bacteria-tolerant phenotype

– Tolerance of bacterial colonization

– No evolutionary pressure towards virulent bacterial phenotype

• Patients with recurrent symptomatic UTIs– Maintenance of aggressive antimicrobial response typical of the normal

urinary tract

– In response evolution of pathogens toward virulent phenotype

– Temporary clearance of pathogen at expense of infective symptoms

• Key role for HD-5?– Expression increased significantly in ureter after diversion

– Trend toward greater ileal and ureteral HD-5 expression in rUTI group

• Next steps– Comparative longitudinal analysis of HD-5 urinary content

– Related to phase of infection – clearance – re-infection

– Define therapeutic potential

What might this mean clinically?

Pathway modulation

• Host– Epithelial recognition

– Signalling pathway

– Effector gene transcription

– Effector interaction

• Bug– Adaption

– Interaction with environment

– Virulence factors

– Invasiveness

New drugs

Needed because of ↑ antibiotic resistance

Alternatives to antibiotics – Identify

asymptomatic patients and encourage less

antibiotic use through patient education

100 women with cystitis treated with 3 days antibiotics:

NHS patient decision aid

Current alternatives

• High fluid intake

• Analgesia

• Urinary alkalinising agents x/

• Cranberry preparations x/

• Methenamine x/

• Pro-biotics x/

http://www.cks.nhs.uk/

Need more - urgently

Summary

• We know more about the bugs– Changing

phenotype/adaptatability

• We know more about the host– Defences

– Tolerance vs Response

• Need to put it together– New treatments strategies

– Stratify risk

• Induce tolerance

• Induce/enhance response

Acknowledgements

The workers

• Dr Judith Hall

• Dr Claire Townes

• Ased Ali

• Marcelo Lanz

+

• Wendy Robson

• Marian Haskin/Liz Davis/Helen Lake

• Kieran O’Toole

• Natasha Rigas

• Craig Robson

+

• The participants and urine collectors

Funding

Any Questions?

Read more!?

• Ali et al J Urol 2009: 182; 21-28

• Townes et al Urology 2010: In press

• http://www.uroweb.org/fileadmin/EAUN/guidelines/EAUN_IU_Guidelines_EN_2009_LR.pdf

• Sivick KE and Mobley HLT. Waging War against Uropathogenic Escherichia coli: Winning Back the Urinary Tract. INFECTION AND IMMUNITY 2010; 78:568–585

• Weichhart et al. Current concepts of molecular defence mechanisms operative during urinary tract infection. Eur J Clin Invest 2008; 38 (S2): 29–38