# Presentation: 279782

## Monitoring for Anti-retroviral Therapy

- Frances Pouch Downes, Dr.P.H.
- APHL Botswana Country Lead

## Clinical Implications

- CD4
- Indicator of immune-system integrity
- Aid to determining initiation of ARV
- Disease staging

- Viral Load
- Indicator of disease progression
- Aid to monitoring response to anti-retroviral therapy
- Aid to determining initiation of ARV

## Technology Selection

- Facilities
- Personnel
- Cost of reagents and equipment
- Local/regional expertise for training, proficiency measurements, surge capacity
- Demand, test volume expected
- Geographical and population distribution
- Sustainable QA program
- Regional technical support from vendor
- Equipment maintenance demand, robustness

## General QA Considerations

- Organization
- Personnel training, competency
- Equipment
- Purchasing and inventory
- Process control
- Quality Control
- Standard Operating Procedures
- Specimen integrity

- Documents and records, reporting format
- Occurrence Management
- Assessment
- External Quality Assessment (PT)
- Verification
- Process Improvement
- Services and Satisfaction
- Facilities and Safety

## Slide 6

## Projected Manpower & Equipment Needs HIV Treatment of MTCT Population

|  | Daily Workload | MTCT | Manpower | Equipment |
| --- | --- | --- | --- | --- |
| Rapid Tests | 50/Technician
10/Counselor | 60,000 |  |  |
| HIV ELISA | 200/Technician |  |  | +6 ELISA Setups |
| CD4 | 30/Technician | 24,000/32,000 | (8/10) 18 Technicians | +4 Flow  Setups |
| Viral Load | 30/Technician | 24,000/32000 | (8/10) 18 Technicians | +4 units |

## Laboratory Facility Requirements

- Adequate and consistent power
- Adequate and consistent water
- Temperature and air quality control
- Biosafety Level 2
- Sealed floors and benchtops
- Handwashing/shower facilities
- PPE and other Universal Precautions Practices
- Security
- Communications (phone, network)

## Slide 9

## CD4 testing Frequency

- Initial visit
- If CD4 > 500 and viral load 10,000-20,000, every 6 months
- If CD4 350-500 and viral load 10,000-20,000, consider ART
- If CD4 < 200, recommend ART

- IDSA recommendation, 2000

## CD4 Technology Options

- Flow Cytometry
- Single platform
- Double platform
- EIA
- Microscopy

## CD4 QA Considerations

- Stored and transported at room temperature
- Tested within 72 hours
- Proficiency testing

## Comparison of  Viral Load Methods

|  | RT-PCR | b-DNA | NASBA |
| --- | --- | --- | --- |
| Manufacturer | Roche Amplicore
Ultrasenitive | Chiron | Organon-Teknika |
| Analytical sensitivity 
(copies/ml) | 400
50 | 500 | 4,000 |
| Accuracy range | 400-750,000
50- 5,000 | 500-1,000,000 | 4,000-2,000,000 |
| Inter-run reproducibility | 0.3  | 0.3 | 0.3 |
| Anticoagulant | EDTA/ACD | EDTA | EDTA/ACD/
Heparin |
|  |  |  |  |

## Viral Load Testing Frequency

- Baseline: 2 measurements, 2-4 weeks apart
- During therapy:
- Routinely 3-4 months
- Shorter as critical decision points near
- 1-3 months after changing therapy

## Inappropriate Test Usage

- Initial diagnosis of HIV infection
- Emphasis on a single specimen result
- Mixing multiple test systems or anticoagulants

## Viral Load Quality Assurance Considerations

- Specimen integrity
- Proficiency testing
- Unidirectional workflow
- Contamination prevention

## Slide 17

## Additional Management Issues

- Data and result management (LIS, HIS)
- Support personnel
- Shipping logistics, cost and access
- Housing
- Laboratory personnel shortage
- Period assessment of laboratory needs and capacities