Implementation of an AFB Smear Microscopy External Quality Assessment Program in Zambia GABERONE BOT - PowerPoint PPT Presentation

1 / 15
About This Presentation
Title:

Implementation of an AFB Smear Microscopy External Quality Assessment Program in Zambia GABERONE BOT

Description:

BWALYA RUTH TEMBWE. PRINCIPAL SCIENTIFIC OFFICER. CHEST DISEASES LABORATORY ... National Reference Laboratory (CDL) in Lusaka. No previous organized system for ... – PowerPoint PPT presentation

Number of Views:146
Avg rating:3.0/5.0
Slides: 16
Provided by: stud1281
Category:

less

Transcript and Presenter's Notes

Title: Implementation of an AFB Smear Microscopy External Quality Assessment Program in Zambia GABERONE BOT


1
Implementation of an AFB Smear Microscopy
External Quality Assessment Program in
ZambiaGABERONE BOTSWANA29, July 2003
  • BWALYA RUTH TEMBWE
  • PRINCIPAL SCIENTIFIC OFFICER
  • CHEST DISEASES LABORATORY
  • (NATIONAL REFERENCE LABORATORY FOR TUBERCULOSIS)
  • LUSAKA, ZAMBIA

2
Tuberculosis (TB) in Zambia
  • 512 TB cases per 100,000 population (10.6 total
    pop.)
  • Direct AFB sputum microscopy
  • - most cost effective for diagnosis and
    monitoring treatment
  • 154 AFB smear microscopy centers
  • National Reference Laboratory (CDL) in Lusaka
  • No previous organized system for assuring the
    quality of TB smear results in laboratory network

3
Map of Zambia showing 9 Provinces
4
Zambia TB Microscopy National Action Plan for
2002 2003
  • National Action Plan for AFB Smear Microscopy
  • external quality assurance (EQA) developed
    June 2002
  • Central Board, MoH, CDL and Province Laboratory
    Managers
  • Onsite laboratory evaluation form modified by lab
    managers
  • Based on the External Quality Assurance
    Guidelines developed by International Work Group
  • Support for EQA from CDC also JICA and WHO

http//www.aphl.org/Infectious_Diseases/EQA.cfm
5
Components of AFB Microscopy External Quality
Assurance
  • (1) On-site evaluation of the microscopy
    laboratory
  • -microscopes, registers, reporting
    results, techniques, etc.
  • (2) Panel testing (PT) of technicians who read
    and report AFB smears
  • -competency in detecting and
    quantification of AFB in smears
  • (3) Blinded rechecking of smears randomly
    selected by a statistical method
  • -determines of errors in a statistical
    sample of slides read in a laboratory

6
Implementation of EQA Activities
  • In phases starting with 9 provincial hospital
    laboratories
  • On-site evaluation was done consecutively with
    PT in each province hospital laboratory
    (September 2002 to January 2003)
  • Province Mangers will conduct onsite evaluation
    and PT in their respective district and rural
    laboratories

7
Implementation of Panel Testing
  • CDL determined the AFB technicians in each
    Province Hospital Laboratory for PT slide
    preparation
  • Communication with Public Health Directors
    regarding EQA activities
  • Preparation of schedule for onsite laboratory
    evaluation and Panel Testing (PT) of AFB
    microscopists in each province
  • Technical support and consultation with
    CDC-Atlanta on preparation and validation of
    slides to be used for PT

8
Implementation of EQA Activities (continued)
  • Batches of PT smears developed at CDL based on
    EQA guidelines
  • Smears were negative 1-9 1 2 and 3 AFB
  • AFB in smears validated at CDL, UTH CDC-Atlanta
  • 10 slides per technician 5 stained at CDL and 5
    un-stained to be stained by technicians
  • Successful completion of PT challenge was at
    least 80 score

9
Onsite Evaluation and PT
  • Total time involved was at least three days for
    each laboratory
  • Courtesy calls to Province Health Director and
    Laboratory Administration
  • Orientation of Laboratory staff to PT and onsite
    evaluation process
  • Panel testing about three hours
  • 1½ - 2 hours for 10 slide test
    evaluation
  • 5 slides pre-stained at CDL 5 stained
    by each technician to be tested
  • On site evaluation, about 2 hours
  • Equipment, procedures and laboratory register
    assessed
  • Corrective actions discussed with technicians,
    about 1 hour
  • Scoring PT and documentation of onsite visit
    results
  • Travel time one day

10
Province Panel Test Results
  • PT success rate 52 at province laboratories
  • Types of errors high false negative and
    quantification were most common
  • PT and onsite exercises were received positively
    by managers and technical staff
  • Staff and managers were receptive to discussing
    opportunities for improvement
  • Communication - a very important factor !!!

11
Panel Test and Onsite Evaluation Workshop
  • 3 day re-training workshop
  • Re-training on quantification of AFB smears
  • Appropriate preparation of stain reagents
    specimen labeling, etc.
  • Attention was given to equipment, reagent and
    technical needs in the laboratory
  • New microscopes had been distributed to some
    laboratories others were still in need
  • Weigh balances were needed
  • More detail on Zambia PT to be presented at
    IUATLD Meeting (Paris, France - October 2003)
  • Participants were also oriented to the Rechecking
    program

12
Implementing Blinded Rechecking
  • Determine of smears performed in each
    laboratory
  • Determine the number of positive smears in the
    laboratory
  • Slide positivity rate
  • Distribute slide boxes to archive slides
    consecutively for one quarter
  • Storage of slides began on 1st April 2003
  • For ease of random collection of slides
  • - each sample received in the laboratory
    is given an
  • individual number
  • May 2003 - supervisory visit to check on the
    progress of slide storage and management of
    laboratory register

13
Initiation of Rechecking Program
  • First supervisory findings
  • Some laboratories were following the recommended
    procedures
  • Two laboratories had not yet started advised to
    commence on 1st July
  • One laboratory was not grading the positive
    smears
  • Random collection of smears for rechecking to
    begin on 10th July
  • The numbering in the register should be carefully
    checked as some numbers are missed e.g., after
    1099 the next number was 2000 instead of 1100.

14
Resources for EQA Activities
  • Adequate number and dedicated staff at NRL
  • Microscopes (some centers have one for all lab
    work) spare bulbs
  • A reliable mode of transportation/vehicle and
    funds for food/lodging
  • Computer for preparation of forms and
    communications
  • Slide boxes to store 3-4 month volumes of slides
    per laboratory
  • AFB Microscopy EQA Guideline for International
    Laboratories
  • Consultation with others involved in AFB
    Microcopy EQA activities

15
Acknowledgements
  • Financial and technical support
  • Centers for Disease Control and
    Prevention-Zambia
  • Japanese Inter Cooperation Agency
  • World Health Organization
  • Ireland AID
  • Consultants
  • Centers for Disease Control and Prevention,
    Atlanta, GA (USA)
  • Dr. John Ridderhof
  • Dr. Bereneice Madison
  • TWATOTELA
Write a Comment
User Comments (0)
About PowerShow.com