1 in 40 patients presenting to UK emergency departments has HIV.

An anonymous survey in Brighton of male patients aged 18-50 reporting to GPs and to hospital accident and emergency (A&E) departments with symptoms suggestive of HIV infection has found an overall HIV prevalence of 1% in those previously undiagnosed with HIV. However, it found a higher prevalence of 2.5% among the patients turning up at A&E, suggesting that, at least in a high-prevalence town like Brighton, there is scope for 'opt-out' HIV testing to be introduced in emergency settings.

The study, presented recently at the BHIVA Conference, Belfast, was carried out using residual blood samples left over from patients who had presented to local GP practices and emergency departments between January 2006 and June 2007 and was an anonymous unlinked survey.

In order for samples to be tested, patients had to have presented with flu-like symptoms, muscle and joint aches, fever, night sweats, rash or mouth ulcers or a combination of other symptoms suggestive of primary HIV infection.

Samples were tested for HIV antibodies and the HIV p24 protein (which appears earlier than HIV antibodies in infected people). Pooled samples were also tested for HIV RNA (i.e. given a viral load test) in order to identify people in primary infection before seroconversion.

A total of 686 samples were tested, and 7% of these tested HIV positive. Eliminating patients known to have HIV, this left 1% of patients (7 samples) who tested positive for HIV and were undiagnosed. One of these samples tested positive for primary HIV infection. It was recorded that 33 of the 686 patients had taken a same-day HIV test, but all were negative.

A total of 71% of samples were collected from GPs and 29% from A&E departments; the proportion of undiagnosed patients attending GPs was only 0.4% (1 in 250) but the proportion attending A&Es was 2.4% (1 in 40). Patients presenting with flu-like symptoms to a GP are unlikely to have investigations carried out.

The study therefore did not support the use of pooled RNA testing as a means of picking up on primary HIV infection in the community. However, the author did suggest that there is a case for routine HIV testing in A&E departments.

Nambiar K, et al. 2008. Fourteenth BHIVA Conference, Belfast. Abstract O5.