Post on 19-Dec-2015
transcript
Laboratories And EQA for effective Tuberculosis Control Programe
Gokarna Raj GhimireSenior Medical TechnologistNational Tuberculosis Center
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Introduction• The global burden of TB is high• Untreated smear positive cases are highly
infectious• Nepal has steady case finding rate (75%)• Treatment success rate (90 %)• Slide positivity rate still on average 10 % • DO NOT miss diagnosis• DO CORRECT TREATMENT FULL DOSE FULL PERIOD
OF TIMR2
• Laboratories and lab networks are a fundamental component of NTP.
• It provides testing for diagnosis, treatment monitoring, evaluating the success of treatment and surviellance.
• Laboratory should do:– New Initiatives– Strengthen the lab capacity including HR– Implement rapid and new diagnostic tests– Implement quality system and safety system
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• Strength of lab network reflects the success of NTP
• Good quality microscopic centers (ZN technique)• Fluorescence Microscopy (Auramine techniques)• Culture and DST (Solid and Liquid)• Molecular techniques, (Gene Xpert, LPA)• Trained staff• Good Quality management System
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Microscopy
• Microscopy remains mainstay of rapid, cheap, easy method of TB case detection
• ZN smear is still the most common test.• Low sensitivity, so look for advanced method • FM has high sensitivity• Concentrated technique with FM has more higher
sensitivity• Monocular microscope-binocular-fluoresence
microscope5
Culture and DST• Confirmed diagnostic test• Need high quality lab infrastructure, equipments and
HR• Useful diagnostic tools for EP cases, childhood TB
cases, HIV-TB cases, MDR-TB Cases, XDR-TB cases• FLD/SLD DST • Facilities are available at NRL/NTC and GENETUP• Purposed places: BPKIHS Dharan, RTC Pokhara, Mid
west Surkhet7
Nucleic Acid Amplification tests
• Gene Xpert : Fully Automated, Cartridge based, Real Time, Nucleic Acid Amplification Test (NAAT)
• LPA: Manual PCR, Detection by Hybridization strip,
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External Quality Assessment (EQA)
• A system for objectively checking the laboratory’s performance using an external agency or higher authority
• Ensures customers (physicians, patients and health authorities) that the laboratory can produce reliable results
• An indispensable part of a laboratory quality management system
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The Quality System
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EXTERNAL QUALITY
ASSESSMENT
EXTERNAL QUALITY
ASSESSMENT
Quality System Essentials (QSE)
Set of coordinated activities that function as building blocks for quality management
Quality System Essentials (QSE)
Set of coordinated activities that function as building blocks for quality management
Requirements Regarding EQA
• The laboratory should participate in inter-laboratory comparisons such as those organized by EQA schemes ( Total 554 Microscopy centers are exists in Governmental organization and NGO/INGO/Private institution)
• The lab management shall monitor the results of EQA and participate in the implementation of corrective actions
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EQA Benefits• Allows inter-lab comparison of performance• Serves as an early warning system• Identifies systematic problems • Provides objective evidence of laboratory quality• Serves as an indicator for focusing improvement efforts• Identifies training needs• Source of continuing education• Source of material for practice
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EQA for AFB Smear Microscopy
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Consensus document: External Quality Assessment for AFB Smear Microscopy (2002)
Current EQA Structure
National
Regional
District
Local PMC PMC PMC PMC PMC
DTLO DTLO
QCA at Regional Quality Control
Centre
= Slides = Feedback
QCA at National Quality Control Centre (NTC)
If 100% slides correct
If some slides incorrect
Problem slides
DTLO holds meeting to discuss results with PMCs
Structure of Quality Control System
National TB Centre
EDRGoN/BNMT
CDRNTC WDR
RTCMWDR
GoN
FWDRGoN/FAITH
Central level
DPHO/DHO District level
Regional level
Microscopy CentrePeriphery level
Flow of Quality Control System
On Quarterly Basis
1. Keep all Slides
Microscopy Centre
3. Cross Check Assessment (QC 2)
Regional QualityControl Centre
2. Send Collected Smear Slides With Form (QC 1)Selecting by using LQAS
5. Supervision Refresher Training
RTLO
DTLO
Report Feed-Back(QC 3)
EQA Methods for AFB Smear Microscopy
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External Quality Assessment (EQA) –
a process to assess laboratory performance; allows to assess labs’ capabilities and performances by comparing their results with those obtained in other labs in the network
On-site supervision
Panel testing
Blinded rechecking
Panel Testing Process
• NRL sends out sets of stained and/or unstained sputum smears for testing
• Laboratory technicians analyze smears and return results to NRL
• Results are evaluated, scores are sent to participants
• Appropriate corrective actions are undertaken (and documented), if needed
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Blinded Rechecking• Random sampling of routine slides from a peripheral
laboratory for rechecking by a higher-level laboratory
• The widely used system for rechecking of “10% of negative and 100% of positive smear” is no more recommended
• The proposed blinded rechecking method is based on the Lot Quality Assurance System (LQAS)
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On-Site Supervision• Periodic visits to the laboratory to assess laboratory
practices to:• Obtain a realistic picture of laboratory practices• Provide assistance with problem areas, including training
• Laboratory vs. TB supervisors• When planning site visits, to consider:
–Frequency–Use of checklists–Follow-up visits
• Monitoring corrective actions• Training
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EQA methods: Which one is better?
• Advantages and drawbacks for all types• Influencing factors:
– NTP goals set up for laboratory services development
– TB prevalence in the country– Centralization / decentralization of health services – Resources available and projected
• Cost, time• Logistical questions
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Panel Testing
ADVANTAGESADVANTAGES DISADVANTAGES:DISADVANTAGES:
•Low workload for a peripheral center
•Improves laboratory credibility
•Rapid response countrywide possible
•Use of stained and unstained smears can help to identify the source of a problem
•May lead to identification of faulty equipment
•Does not measure routine performance
•High workload for NRL
•May not be motivating to improve daily performance
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Panel Testing: Indications for Use
• Minimal first step for EQA with limited resources• Rapid assessment of gross deficiencies • Evaluates proficiency of laboratory technicians
prior to and following training • A tool during problem-oriented supervision
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Blinded Rechecking
ADVANTAGESADVANTAGES DISADVANTAGES:DISADVANTAGES:•Low workload for a peripheral laboratory
•Motivates to improve daily performance
•Reflects reality of routine performance
•Higher workload for a higher level center
•Needs close adherence to elaborated procedures
•Can not be used with very low positivity rates
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Indications for use:
• The best method for evaluating lab performance
• Countrywide
• Ongoing and permanent
On-Site Supervision
ADVANTAGESADVANTAGES DISADVANTAGES:DISADVANTAGES:
•Direct personal contact
•Motivating to staff
•Observation of actual work
•Identifies causes of errors
•Permits verification of equipment quality and function
•Usually poor coverage
•Labor intensive
•Costly
•Needs very good supervisors
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On-Site Supervision: Indications for Use
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• Complementary to rechecking and panel testing for constructive feedback and problem solving
• Implementation and monitoring of quality improvement measures
• Data collection and flow of information among laboratory levels
EQA: Important Issue
Blinded rechecking or panel testing should be complemented by very targeted problem-oriented supervision conducted by a trained staff
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Situational Analysis Of EQA Nepal
• Medium Size Population; • Vast different territory• Low Burden of TB • Several hundreds of geographically dispersed peripheral
laboratories• RQCC’s (Intermediate laboratories’) infrastructure is not
well developed; many intermediate labs experience lack of staff
• NRL/NTC is not well equipped and sufficient staffed
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Key Messages (I):• EQA can be defined as a system for objectively checking the
laboratory’s performance using an external agency or facility
• EQA for AFB smear microscopy allows participating laboratories to access their capabilities and performances by comparing their results with those in other laboratories in the network
• EQA for AFB sputum smear microscopy include three methods:– Panel testing– Blinded rechecking– On-site supervision
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Key Messages (II):
• Effective use of each of EQA methods will highly depend on resources, NTP goals, TB prevalence, health services’ structure and the stage of laboratory quality assurance activities development in the country
• Blinded rechecking or panel testing should be complemented by very targeted problem-oriented supervision conducted by a trained staff
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