Utilizing the microbiology laboratory for optimal patient care Dr Shobhana P Kulkarni Medical Microbiologist MBBS, FRCPath, FRCP(C) Faculty /Presenter Disclosure • Faculty: [Shobhana Kulkarni] • Relationships with commercial interests: – Grants/Research Support: None to disclose – Independent medical contractor to DynaLIFEDX diagnostic laboratories – Speakers Bureau/Honoraria: None to disclose – Consulting Fees: None to disclose – Other: none to disclose Disclosure of Commercial Support • This program has received financial support from DYNALIFEDX in the form of EDUCATIONAL PROGRAM • This program has received in-kind support from DYNALIFEDX in the form of LOGISTICAL SUPPORT • Potential for conflict(s} of interest: • • Dr. Shobhana Kulkarni has received NO HONOURIAMUM AND IS A CONTRACTOR WITH DYNALIFEDX DYNALIFEDX PROVIDES LABORTAORY SERVICES WHICH WILL BE DISCUSSED IN THIS PROGRAM. Mitigating Potential Bias • DYNALIFEDX OPERATES IN ACCORDANCE WITH ALBERTA HEALTH SERVICES, TESTING AND SOLUTIONS ARE A DIRECT RESULT OF PROVINCIAL STANDARDS. Objectives Good patient care relies on 3 critical steps in laboratory testing: 1. Ordering a test only when indicated 2. Providing a good quality specimen 3. Interpreting the report correctly Case vignette • An 82-year-old LTC resident with fever and productive cough – No urinary/ other symptoms – Chronic ulcer on the lower extremity is unchanged • A “pan-culture” is initiated: – Sputum and blood – Urine – Ulcer 6 Culture results • CXR: Normal • Sputum: Gram stain: no WBCs, no organisms • Sputum culture: 1+ Candida albicans • Urine culture: ≥107 CFU/L of E. coli • Wound culture: 4+ VRE 7 • The patient is treated with: – Fluconazole for the Candida in the sputum – Cipro for the E. coli in the urine – Linezolid for the VRE in the wound • Two weeks later the patient has diarrhea and C. diff toxin assay is positive 8 • The only infection this patient ever had was a viral upper respiratory tract infection!!!! 2 types of microbiology tests • Screening in asymptomatic patients – MRSA, VRE – Asymptomatic bacteriuria in pregnancy – HIV, CT/GC etc. • To confirm diagnosis in symptomatic patients – UTI, wound infection, pneumonia etc. Limitation of diagnostic tests • A positive culture doesn’t always mean infection. “False positives” caused by: • Contamination from patients’ flora, collectors’ hands, or environment • Overgrowth during storage/transport When to order diagnostic tests • Diagnosis of infection is based on clinical findings, not laboratory testing alone • Tests should be ordered ONLY if symptoms/signs of infection present – “Choosing Wisely Canada” – April 2014 Outcomes of unnecessary tests Patient distress Waste of finite resources Unnecessary antibiotic treatment Effects of unnecessary antibiotics • HARMS patient – Unnecessary drug adverse effects, e.g. C.difficile – Increased risk of getting infection • Increases antibiotic resistance • Wastes valuable and finite healthcare resources CASE VIGNETTE 75y diabetic lady with worsening leg ulcer. Clinically infected. Culture is indicated. Dressing removed and swab taken of pus. Case vignette • Smear of specimen: 4+ WBC, 4+ bacteria (many types) • Culture: 4+ coliforms x3, Enterococci x2 • Report: “Mixed growth suggestive of contamination with colonizing flora. Repeat swab AFTER cleaning.” DELAY in result and therefore treatment Collecting wound swabs Clean surface of wound with sterile saline – to remove colonizing flora Then rub swab firmly on wound to collect offending pathogen What is good laboratory utilization? 2. Providing good quality specimen 1. Ordering tests ONLY when symptoms of infection 3. Correctly interpreting result Optimal patient care Good quality specimen 1. To ensure pathogen is recovered: • Collect BEFORE starting antibiotics • MSU – PREFERABLY, collect 2-4hrs after last void • Tissues and fluids/pus better than swabs 2. For accurate result: • Prevent contamination during collection: – – – – MSU – verbal AND written instructions CSU – remove old if >14d; aseptically side port Wound – CLEAN superficial slough/pus first BC – skin antisepsis first Good quality specimen 3. To prevent overgrowth of pathogen/commensal flora after collection: • Urine: Transfer within 20 mins into grey-top, boric acid tubes • Sputa, swabs: Store in fridge if transport to lab>2h 4. For quick result: • Label requisition and specimen FULLY • Provide clinical details – why test is being requested • Transport to laboratory ASAP Correct interpretation of the report • 76y male. Chronic venous leg ulcer Wound swab report: –1+ WBC, 2+ GPC, 2+GNB. –Growth: 4+ S.aur S/clox, SXT; 2+E.coli • 50y female; indwelling catheter; urine cloudy Urine report: ≥ 107 E.coli. ESBL+. S/ gentamicin, ertapenem Comment: Do NOT treat if asymptomatic Getting the correct answer • JOINT responsibility of the submitter AND laboratory – Laboratory processes are quality assured – Submitter processes are not – major influence on quality of result • Responsibilities differ • BOTH equally important Enhancing specimen quality is everyone’s responsibility!! Improving laboratory utilization 1. Clinical decision support tools • DL website - test directory, other educational information • Lab dedicated phone line, on call microbiologist – 24/7 • Electronic Physician Order Entry -in development • Diagnostic algorithms, e.g. UTI checklist in LTC Improving laboratory utilization 2. Education • Ongoing education/training of all staff and students • In service, posters in specimen collection areas, apps on test ordering and result interpretation for students 3. Format of reporting • • Reporting with interpretive comments Restrictive reporting – if clinical indication not stated. Need to phone in for result Take home message 3 Critical steps in ordering a test 1. Are symptoms/signs of infection present? 2. If so, obtain a good quality specimen 3. Correlate the result with patient’s symptoms BEFORE decision to Rx Enhancing specimen quality is everyone’s job!!