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To Screen Or Not To Screen In Suspect Urinary Tract Infections

BCPSQC Quality Forum 2014 Session F1 February 28, 2014

Vancouver General Hospital Laboratory

VCH Regional Laboratory Medicine Lower Mainland (LM) Laboratories

Anita Kwong, Director, Quality and Process Improvement, LM Laboratories

Anita.Kwong@phsa.ca

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Project Team

• Disclosure: No project team members has affiliation (financial or otherwise) with a commercial organization that is related to this presentation

Multi – Discipline Collaboration Team Members

VGH Medical Biochemistry Dr. Morris Pudek, Adelina Lim, Karen Ng, Alisha Thompson, Biochemistry technologists

VGH Medical Microbiology Dr. Diane Roscoe, Charlene Porter, Jackie O’Connell, Microbiology technologists

VCH Operations Richard Walker Sharon Stapleton

LM / VCH Labs Quality Team Sara Garcha (up to Oct 2013) Anita Kwong

Data Analysis Jason Pal (up to Dec 2013)

VCH Regional Laboratories Vancouver General Hospital

VCH Regional Laboratories: – Include 11 sites – VGH – One of the largest

diagnostic laboratories in Western Canada

– Referral centre for other VCH Laboratories

– Referral centre for special tests across the province

Who We Are Laboratory Physicians, Medical

Technologists and Medical Laboratory Assistants working in: • Medical Biochemistry • Hematopathology • Medical Microbiology • Transfusion Medicine • Anatomical Pathology • Cytology • Cytogenetics and Molecular

Genetics • Transplant Immunology

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Patients We Serve at VGH Laboratory

Partial list of samples / procedures Per day

Blood collections (lab staff procedures only)

900

Chemistry samples 1,800

Chemistry urine samples for urinalysis 140

Microbiology samples 1,100

Microbiology urine samples for culture 185

Urinary Tract Infections (UTI) • 1 in 3 women will experience UTI by age 24 • Female lifetime probability of UTI is >50% • UTI most common bacterial infection for both

hospitalized and community patients • Major healthcare cost driver:

• VCH: UTI is the most common Hospital-Acquired Infection (HAI), 18,900 cases over 4 years, $16.3m in costs (Raschka, S. 2012. Health Economic Evaluation of Quality and Patient Safety Within an Organization, Quality Forum 2012.)

• Diagnosis and Management algorithm

• Gold standard for bacterial cause of UTI = culture

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Urinalysis • If laboratory testing is required, perform urinalysis

dipstick first: • May be automated • Costs ~$0.30 • Results ready in 2 minutes

• If dipstick positive → microscopy for cellular elements

• Microscopy is labour intensive • Costs ~$5 (labour) • Results ready in 1-2 hours • At VGH, of 140 urinalysis requests per day, 30% require

microscopy exam

• Outpatients UTI laboratory protocol: – dipstick leukocyte and/or nitrite positive → urine culture

• Inpatients: – Urinalysis and urine culture are independent orders

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Urine Cultures

• Urine cultures for bacterial cause of suspect UTI • Labour intensive • Costs ~$5 to $40 per culture • Results ready in 1 to 2 days • At VGH, 185 urines are processed for cultures per day

• Many patients are treated with antibiotics without culture results being known

• Many UTIs are diagnosed without the supporting information of a urinalysis

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New Technology • Current technology:

– Dipstick, microscopy, urine cultures

• New technology: • Flow cytometry uses scattered

light which reflects the size and volume of each cellular element, e.g. WBC, RBC, and bacteria.

• Fluorescent stains specifically targets mitochondrial and nuclear DNA of these cells.

• Cellular elements are counted and quantitative values are available in minutes.

New Approach to UTI Diagnosis

Automated Urinalysis +

Fluorescent Flow Cytometry (FFC) =

Rapid and powerful tool to screen urine samples for

absence / presence of UTI

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Cross Discipline Collaboration

• Evaluation of Fluorescent Flow Cytomery (FFC) at VGH laboratory

• September 18 to October 18, 2013 • Urine samples (n=432) were tested for:

• Urinalysis & FFC on instrument A • Urinalysis & FFC on instrument B • Urine cultures – read at 24 hours and 48 hours

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Study Findings * Using urine culture results as gold

standard: • FFC threshold was identified to correlate

to negative cultures • Sensitivity 90% • Specificity 74%

• Applying the FFC threshold in this study: • Of 430 urine samples, 257 (60%) would

not have been cultured using FFC negative bacteria count cutoff

(Both instruments A and B yielded similar results)

Correlating Results Biochemistry Microbiology

430 urine samples in FFC study

185 urine samples for culture per day

60% would not have been cultured

40% no growth 19% no significant growth

FFC negative

Results in 5 minutes No growth or no significant growth

Results in 1 to 2 days

Cost of urinalysis and FFC $1.50 (excluding capital cost)

Cost savings for not processing no growth urines: ~$135K per year

Reference: US study reduced

unnecessary urine cultures by 55%

Gieson, Greeno, Thompson et al, 2013. Clin Biochem.

Surrogate Marker for No Growth Urine Culture Results

Available in <1 hour

• Patient Safety Benefits: • Avoids unnecessary antibiotic treatment • Potential reduction of side effects related to

antimicrobial therapy

• Systems Benefits: • Reduces healthcare costs • Reduces laboratory operations cost • Promotes team building across laboratory

disciplines

Next Steps • Validate findings with identified patient

groups • Validate findings with samples specifically

ordered for urine cultures • Laboratory workflow re-design across

Biochemistry and Microbiology • Collaborate with clinical partners to change

practice of laboratory UTI diagnosis

Thank You!

Questions