THIS PRESENTATION WAS
PRESENTED AT APOLLO INTERNATIONAL
FORUM ON INFECTION CONTROL
(AIFIC’ 2013), CHENNAI
The presentation is solely meant for Academic purpose
ROLE OF MICROBIOLOGY LABORATORY IN INFECTION CONTROL
ROLE OF MICROBIOLOGIST IN ORGANIZING THE LAB
Lab results form an integral part of the complex decision making process and may influence upto
70% of medical diagnosis
To ensure the same, the lab has to issue quality reports
Quality of report relies on quality of clinical specimen submitted
To avoid pre-analytical errors, lab has to putforth
Specimen acceptance & Rejection criteria
Specimen to be submitted with relevant clinical details
Open and free communication between Clinicians & Microbiologist / Micro Lab essential
Facility to access patient records preferred (healthcube)
CRITERIA FOR REJECTION OF SPECIMEN
Problem Action
Improper or no label Telephone the nurse or physician , process the specimen but do not issue the report
Prolonged transport Alert the concerned staff & request a repeat specimen
Improper container Do not process & request a repeat specimen
Leaking container Do not process & request a repeat specimen. Protect the laboratory staff
Oropharyngeally contaminated
Do not report or process. Indicate the discrepancy & request another specimen
Obvious foreign contamination
Alert the concerned staff & request a repeat specimen
Problem Action
Duplicate specimens submitted on same day for same request
Refrigerate the specimen, contact the concerned staff. Culture on request only
Specimen unsuitable for culture request e.g., anaerobe request with aerobic transport
Contact the concerned staff, indicate the discrepancy, request a proper specimen
Quantity not sufficient For blood: if < 5ml for an adult, inform the concerned staff, request another specimen. Process but add note on report
For other specimens: if quantity not sufficient for multiple requests, call the physician and determine the priority of request
Specimen Collection, Transport and Processing:
General Instructions for collection of culture specimens
Select the correct anatomic site
Collect the specimen using proper technique & supplies
Package the specimen in appropriate container
Transport promptly to the lab within 2 hrs of collection
Conditions of transport & storage of samples
Profound influence on their usefulness
Follow standard techniques to process samples
Fulfill quality control requirements
Quality Control check for media and stains
Potency testing for antibiotic disk
Sterility check for collection containers
Identify causative organism to species level
Use of automation helps speedy isolation &
identification
- Automated blood culture systems
Automated ID & sensitivity systems
Interpret results judiciously
Differentiate commensals / colonizers from
pathogens
Perform quantitative cultures wherever required
ANTIBIOTIC SENSITIVITY TESTING
Kirby-Bauer Disk Diffusion Method – Points to remember :
McFarlands Standard for inoculum preparation
Depth of the media and pH
Proper storage of antibiotic disk
Proper placing of the disk- use template
16 – 18 hrs of incubation
24hrs for Staph and Entero
- Oxacillin & Vancomycin
Selection of Anti microbial disk :
Based on type of organism & source of isolate
Formulate Inhouse Antibiotic Policy with reference to
international guidelines
Use 1st line of antibiotics for out patient isolates
2nd line to be used if resistance noted to 1st line & for
isolates from critically ill patients
Use of E-strips for fastidious organisms / CSF isolates /
Ciprofloxacin to Salmonella
Interpret according to International Guidelines
SMF Antibiotic Policy – Restrictive Policy
1ST & 2ND LINE ANTIBIOTICS FOLLOWED AT SMF
1st line of Antibiotics 2nd line of Antibiotics (Restricted)
Penicillin-G Ampicillin Cephalexin Ciprofloxacin Ofloxacin Nitrofurantoin Nalidixic acid Gentamycin Tobramycin Azithromycin Norfloxacin Cotrimoxazole Ofloxacin Amoxy/clav Cefuroxime Cefixime Ceftriaxone (Salmonella) Clindamycin
Amikacin
Ceftazidime
Cefotaxime
Cefepime
Piperacillin/tazo
Cefaperazone/sul
Imipenem
Meropenem
Ertapenem
Aztreonam
Vancomycin
Linezolid
Teicoplanin
Polymixin-B
Colistin
Looking for Resistance patterns: (to guide
antibacterial therapy)
Lab to detect common resistant mechanisms
β-lactamase detection with Cefinase disk
Screening for ESBL & Amp 'C' β-lactamase with
Cefpodoxime & Cefoxitin disk
Performing DDPT for phenotypic confirmation of ESBL
Can be performed while testing 2nd line of antibiotics
Oxacillin & Cefoxitin disk for Staph. isolates
Look for Inducible Clindamycin resistance in Staph isolates
- D Test
Quinolone resistance in Salmonella
- Nalidixic Acid disk as marker
- E-strip to Ciprofloxacin
Detection of Carbapenamase
- Modified Hodge test
- EDTA disk synergy test
Other methods for resistance detection
- Automated ID & Sensitivity System (Vitek 2)
- Molecular methods
Infection Control Critical Values (Early Warning Systems)
Micro lab to inform ICN on a daily basis:
- MDR GNB, MRSA, VRE
- Sputum AFB + cases
Microbiologist to note suspected HAI in HAI chart
Convey to ICN for data collection in surveillance form
Inform notifiable diseases to MRD Chennai Corporation
- Dengue
- Typhoid
- Chikungunya
- Malaria
- Swine flu
Role of Microbiology lab in Hospital Infection
Control
Identifying outbreaks early- Pseudo or true outbreak
Conveying information to ICT & concerned ward/unit
Charting down action plan, control measures
Implementation through ICT
Monitoring effectiveness of control measures
Stock isolates from patients & suspected source
Source identification using phenotypic & molecular
methods
Designing the HIC Plan in accordance with
infrastructure & consensus of user departments
Monitoring key infection control measures along with
ICN
- Hand hygiene practices
- Standard & Isolation precautions
Compiling Culture & Sensitivity Data of hospital
isolates
Periodical review of culture & sensitivity patterns
Analyze sensitivity pattern of isolates from :
- Out patients & inpatients separately
- Pediatric age group and adults separately
- Resistant isolates from that of sensitive isolates
Prepare a chart at the end of the year
To help Clinicians
- to know the common pathogens &
their sensitivity pattern
- to formulate Empirical Antibiotic of Choice
OCCUPATIONAL EXPOSURES – REPORTING
& POST EXPOSURE PROPHYLAXIS
Needle Stick Injuries – Reporting Protocol
Reported immediately to ER Medical Officer
Assess injury & takes action
Enter details in Occupational Exposure Form
Inform ICN & Microbiologist
Source (if known) & Staff evaluation for viral
markers
Micro lab to process samples as Stat
Reports conveyed to Microbiologist & ICN
Counseling done
Post Exposure Prophylaxis:
If source negative for viral markers - only counseling
If source positive consult ID & initiate PEP
If employee vaccinated for HbsAg assess
AntiHBs titres
If titre low booster dose
If negative Re vaccination
If source unknown Anti HBs tires for Staff &
follow up
Employee Health:
Pre employment health check up
Staff in direct patient care tested for :
- HBsAg
- HIV at entry time
- HCV
Vaccination details collected
Vaccination for Hepatitis B (3 doses) if not
vaccinated
Canteen & Dietary staff – Typhoid, Hepatitis A & B
Maintenance staff - Typhoid, Hepatitis B
Bio Medical staff - Hepatitis B
Lab staff – Hepatitis B, Microbiology – Typhoid
Influenza vaccine if there is outbreak
Food handlers health check up once in a year
Anti HBs titres checked after vaccination
Bio Medical Waste management:
ICT to educate hospital staff on waste segregation
Included in the induction training for House Keeping,
Nursing & other para medical staff
Re-education as & when required
ICN monitors segregation on a daily basis
HK Supervisor ensures safe transportation
Handing over to Central facility
Records maintained by HK Supervisor
Thank
You