HIV Point Of Care Testing at GSTT

Helen Dunn Operations Manager, Virology Infection and Immunology DU

‘Same-day’ to POCT

• Virology approached by GUM early 2004 • They wished to replace same-day with POCT clinics in GUM.

• Also wished to set up POCT at a GP site • Wished for advice and support from Virology • Chosen test already in use at C&W GUM

New approach

• Departure – first time non-laboratory staff had done serology test.

• Nurses and health advisers were to carry out test.

• Virology staff offered to train clinic staff.

• Virology staff asked to advise on testing facilities.

Key aspects

• 1. Trust governance - ? Good for patient • 2. Choice of test – only one CE-marked • 3. Training • 4. Quality – QC and QA • 5. Multi-disciplinary • 6. Audit

1.Trust Governance

• Documentation: Operational policy, liaison between medical and laboratory team, cost benefit analysis.

• Conform to Trust POCT policy. Draft policy found.

Pathology now has a POCT manager. Various programs within Trust.

• Advantages and disadvantages clear – 1 hour result instead of 2/3 days – More expensive test but greater patient satisfaction.

– Less sensitive than lab-based assays for early infection – Stress on clinic staff; rapid result. Proper training and support.

2. Choice of test

• Abbott Determine already assessed at Chelsea & Westminster.

• Only test CE-marked at the time

3. Training

• • •

Senior BMS and clinical scientist

. Day and a half course.

Tutorials – half day

– HIV, virus, disease and lab. diagnosis – Principles of the Determine test – Health and Safety; general and test – Quality – QC and QA

Practical instruction – full day

– How to use capillary – How to interpret control – SOPs, result sheets – Testing panel of specimens – Introduction to NEQAS

4. QC and QA

• QC - procedural control in test - Virology lab pre-tests new batches with controls supplied by HPA Standards Laboratory.

- SOPs for QC preparation and performance - Two staff read results.

- Algorithm for repeat testing and confirmation • QA participation in external scheme. ?NEQAS

Both sites – GUM clinic and GP clinic

AUDIT

• • • 1.

2.

Following 3 years of use in GUM clinic: Adapted vertical audit, with clinic cooperation Concentrated on 3 areas: Health and Safety Performance of test 3.

Clinic Procedures Good result with performance and procedures. Only minor re-inforcing of safety measures required.

5. Multidisciplinary approach

Virology advice, training and confirmation.

Consultant and senior scientists GUM medic and Trust Governance Nurses and Health Advisers named individual lead

2008

• 39 staff trained • GUM clinic POCT still going strong.

• GP clinic folded 2007 – needs lots of local support.

• More community POCT clinics planned.

• Audit performed late 2007

Start date Individuals tested Positives HIV prevalence NEQAS

2008

GUM Clinic Community clinic

Oct 2004 1564 45(confirmed) 1 false pos 2.9% All correct Feb 2005 364 11 (confirmed) 3.02% All correct

Findings of GP pilot study.

• One aim had been to encourage African residents to be tested.

• Study* found that the GP service was used significantly more by the Black ethnic community c.f. the GUM clinic: (16.5% v 8.7 % for same period).

• • Fewer MSM at GP c.f. GUM (34.5% v 41.3%) *Surah et al.

Paper submitted to STI

HIV POCT QA update

• Worth doing if multiple sites take it up. THT may provide access to sites.

• ? small number of samples, more often • ?small volumes • ?spiked whole blood – how to preserve, inactivate, ship etc

POCT and CPA

• What is the laboratory’s role in POCT?

• Our Trust taking an ever greater interest.

• Full control of training, routine testing, QC and QA? Suitable accommodation? Accountable to CPA?

• Advisory role? Not responsible for service? CPA not involved?

The Carter Report Review of NHS Pathology Services in England (2006) Re: POCT “..fragmentation of parts of the service, particularly point-of-care services which are increasingly being undertaken by other members of the health care team, often with no reference to pathology services…”

The Carter Report Review of NHS Pathology Services in England (2006) Recommendations (ix) the independent accreditation process is reviewed to ensure flexibility of approach and is extended to cover all providers of pathology services (including point-of care testing)..

(x) all pathology providers, including point-of-care testing providers, are accredited in accordance with a national independent accreditation process….

..and which requires full participation in external quality assurance schemes..

Modernisation Initiative – evaluation of HIV rapid test kits

• Abbott Determine in regular use

•

INSTi

Two other tests:-

Rapidan Tester

blood

Comparison of patients’ samples

ABBOTT INSTI RAPIDAN

Positive Negative fail Positive Negative fail 102 (96.2%) 1 (0.9%) 3 (2.8%) 106 HIV1 positive (sera) 106 (100%) (whole blood) 100 negative 0 0 100 (100%) 0 0 0 100 (100%) 0

Evaluation of 3 kits using QA/QC material

• Results for NEQAS panel samples

NEQAS HIV-1 positive HIV-2 positive HIV negative 1 8 Nos 15 Abbott 15

(100%)

1 8

(100%)

INSTI 11*

(73%)

0 8

(100%)

Rapidan 15

(100%)

0 8

(100%) *2 negative and 2 indeterminate  Only the Abbott assay detected the HIV-2 positive sample Results for 3 internal QC samples

QC sample

Negative HIV-1 positive HIV-2 positive

Abbott

Neg Pos Pos

INSTI

Neg Neg Neg

Rapidan

Neg Pos (weak) Neg  HIV-2 positive sample not detected by INSTI and Rapidan.  INSTI failed to detect the HIV-1 positive and only a weak positive result was given with this sample by the Rapidan kit

Results for HIV-2 positive clinical samples Sample

HIV-1/HIV-2 1 HIV-2

Nos

4

Abbott

1 4

INSTI

1 4* *2 results were very weak, ** 3 results were very weak

Rapidan

1 4**

Evaluation in community

- Several THT clinics each using the Determine. 100 tests at each site.

- Both will run the INSTi and the RAPIDAN in parallel with the Determine.

- A ‘real-life’evaluation of those assays in comparison with Determine: ease of use, safe handling, interpretation.

Chlamydia POCT

• Tests are available on the internet for self testing – all test for antigen. E.g 15 mins • Testing services available on internet – e.g. THT – pack sent to patient who takes own specimen and sends for testing. – 2 days • Gold standard now NAAT.

• Some tests are for ‘own use’, some for ‘professional use’ only.

Sensitivity vs. accessibility

• Debate about choosing less-sensitive over tech.-demanding test to avert STIs.

• Vickerman et al. estimate required sensitivity at only 50% if either 55% fail to return for treatment and there is no transmission, or 80% return and 50% infect partner during delay.(STI 2003) • One rapid Ag test claims sensitivity of 81% c.f. SDA and 83% c.f. PCR. (BMJ 2007).

Final comments

• > 3-year experience of HIV POCT.

• Clinic / laboratory collaboration essential • QA material for POCT needed.

• Lab evaluation of other kits gives concern • Community-based evaluation will be valuable. • Desire for other infectious disease POCT.

•

Virology, GSTT

• Dr. S. O’Shea • Dr. W. Tong • Ms. K. Ashworth • Ms. S. Sliney • Ms. J. Stone •

Lambeth Walk GP

• Ms. Christina Fitzgerald • Ms. Maria Walker • Ms. Andrea Scott

Colleagues

•

Genitourinary medicine, GSTT

• Dr. Emma Fox • Dr. Cindy Sethi • Ms. Chikami Shimada • Ms. Rebecca Bickersteth • Mr. Dilip Lakhani •

Modernisation Initiative

• Keith Marshall