quality in laboratory, the contamination of the sample at any stage preanalysis stage, analytic ,and post analytic stage

1. Quality In Microbiological
Laboratory
Dr : Dina Ramadan
Microbiologist In Central Health Laboratory
Ministry of Health
Quality Manager

2. Juran’s two definitions of
quality
1. "Quality" means those features of products which meet
customer needs and thereby provide customer
satisfaction.
2. "Quality" means freedom from deficiencies-freedom
from errors that require doing work over again (rework)
or that results in field failures, customer dissatisfaction.
09/08/12 2

3. Definition of Quality
“Quality is compliance with
standards.”
QA Project Contract, 1997
“ Doing the right thing, right, the first time.
Doing it better the next time.”
ODI Consulting
(management training and consulting firm )
Meeting the needs and exceeding
the expectations of those we serve
09/08/12 3

4. Quality in laboratory
Patient/Client Prep
Sample Collection
Reporting
Lab quality
Management
Sample Transport
Record Keeping
Sample Receipt
Testing
Test Evaluations
09/08/12 4

5. Pre-analytical factors
• Collection and transporting systems
– Sample collection
• If specimen is collected incorrectly, the
organism will not grow in culture and then
cannot be identified.
• If a specimen contains contaminants that are
identified as causing the infection, the patient
may be treated incorrectly.

6. The lab must have instruction
procedure
the request of analysis must have
some data of the sample e.g.:
Patient’s name, age, gender ,
Type & source of specimen,
 date & time of collection
Clinical note- antibiotic history
collecting samples:
The lab shall have writing instructions for
collecting sample and must be distributed to all
area which samples collected from it
09/08/12 6

7. Transporting
Specimens
Remember:
1. Follow proper collection procedures and use correct
device.
2. Tightly close container ,Label the specimen & complete
requisite form
3. Maintain the samples in a state close to their original as
possible.
4. Protect anyone who handles the specimen
container from exposure to potentially infectious
material.
1. Regularly scheduled daily pickups by the lab
09/08/12 7

8. Rejection of samples
• Laboratory must reject the samples that can give
incorrect result of the lab e.g.:
– Missing or inadequate identification
– Insufficient quantity
– Specimen collection in an inappropriate
container
– Contamination suspected
– Inappropriate transport or storage
09/08/12 8

9. Analytical factors
• Equipment reliability
• Reagent stability, integrity & efficiency
• Adequate calibration
• Proficiency of personnel
09/08/12 9

10. checks for equipments
• Calibration: process which is applied to quantitative
measuring of equipment to assure its accurate operation
throughout its measuring limits.
This done for all equipment in the lab as balance ,
thermometer , autoclave , glassware ,
• Validation: steps taken to confirm and
record the proper operation of equipment
at a given point of time in the range in
which tests are performed
09/08/12 10

11. Quality control of equipments
Equipment Procedure Schedule Tolerance limit
Refrigerator Temp. check Daily 2-80C
Freezers Temp. check Daily + 5 0C
Incubator Temp. check Daily +10C
Water bath Temp. check Daily +0.50C
Anaerobic jar Methylene blue Each use Colorless
P.aeruginosa No growth
Serology Count of Each use 180 +10rpm
rotator revolutions/min
Autoclave Sterilization dick strips Each run Color change
09/08/12 11
Spore strips monthly No growth

12. Quality control of equipments
Equipment Procedure Schedule Tolerance limit
Hot air oven Spore strips weekly No growth
Centrifuge Revolution check by monthly
tachometer
Microscope Stage &lenses Each use
Pipettes Volume delivery check 10 Initially
times
Balances Checked against known Annual
weights
Bio-safety hood Air velocity check 6 monthly Flow 50 +5
ft/min
09/08/12 12

13. Quality control of stains and
reagents
• Each lot of newly prepared stain tested with
positive & negative controls
• Regular testing done:
 Weekly: Gram’s
 Each day of use: ZN stain & other stains
• Discard stains if outdated
09/08/12 13

14. Quality control of Media
Media have role in the results of the microbiological
Lab ,so its quality included in lab, it act as the supplier,
many parameter of media lab must be controlled to
make sure of its preparation :
Sterilization parameter
Autoclaving time: Indicators, Temperature,
Pressure
Physical parameter:
Bubbles/unequal filling/cracks/freezing/pH
09/08/12 14

15. Quality control of Media
Microbiological parameter
Growth supporting characteristics (with both previous
& new batch), productivity of media ,performance
Contamination parameter
09/08/12 15

16. Reagent testing for validation
Procedure Control Expected reaction
Catalase S.aureus Bubbling(+)
Streptococcus spp. No bubbling(-)
Coagulase S.aureus Clot in 4hrs (+)
S.epidermidis No clot (-)
Oxidase P.aeruginosa Purple colour in 30 sec
E. coli No change (-)
Bacitracin S.pyogenes Zone of inhibition(+)
E.faecalis No inhibition (-)
Optochin S. Pneumoniae ZOI(+)
S. viridans No inhibition
Indole E.coli Red ring (+)
09/08/12 16

17. Documentation
All laboratory equipment , procedures, personal
data must be documented, also the document must
stored probably
Example of document in the lab:
• Name and serial number of instrument
• Elements to be checked and kind of data to be
collected
• Frequency of checking
• Record of data
• Signature with date of the person performing these
tasks
09/08/12 17

18. Post analytical factors
The results of the lab must be :
• Accurate recording
• Range of normal values must be written
• the lab must have record of the results and stored
carefully for the patient privacy
09/08/12 18

19. Questions
09/08/12 19