Key learning points:
– A quarter of people living with HIV in the UK are unaware of their condition.
– Early diagnosis and treatment significantly increases the chances of effective control of HIV, making transmission less likely and overall better for individual care.
– With modern anti-retroviral therapy a person infected with HIV can expect to live a healthy life with a normal life expectancy
HIV stands for human immunodeficiency virus. It is a retrovirus that replicates within the CD4 cells (these cells are T helper cells, which form part of the immune system and express the surface protein CD4) of the immune system. Initially, the body is able to replace the CD4 lymphocytes cells (immunological cells designed to ward off infections/parasites) lost through the virus and patients are asymptomatic. However, if left untreated, the virus will eventually cause a time-dependent reduction in the number of CD4 cells, resulting in a weakening of the body’s immune system. This process can take several years.
When the patient’s immune system becomes significantly compromised they are described as having AIDS (acquired immune deficiency syndrome). AIDS is characterised by a reduction in the ability of the body to fight infection. As a result patients with AIDS are very vulnerable to opportunistic infections. Certain diseases are termed ‘AIDS defining’ as they are most commonly seen in this situation; key examples of AIDS defining illnesses are pneumocystis pneumonia (PCP) and Kaposi’s sarcoma (KS).1
The prevalence of HIV and AIDS in the UK
HIV infection is a significant public health problem worldwide, there were over 100,000 people living in the UK with HIV in 2013.2 Of these, approximately a quarter remain undiagnosed.3
Patient’s known to have HIV can be managed with antiretroviral therapy (ART) to minimise viral replication, and therefore, keep viral load as low as possible. Recent developments in ART mean that patients diagnosed with HIV today can expect to live a normal and healthy lifespan.4 Effective ART also significant reduces the risk of transmission of the virus to others.
Unfortunately this positive news is significantly marred by more than 40% of HIV diagnosis in the UK are being made late (CD4 count below 350). Late diagnosis is associated with a 10 fold increased risk of death, largely due to medications only being partially effective at such a late stage.3 Moreover, the later the diagnosis, the higher the cost of management (see Case Study example).
HIV transmission
The HIV virus is most commonly transmitted in the UK by sexual contact. This can be via vaginal or anal sex. There is a small risk of transmission of HIV from oral sex, particularly in the presence of other oral disease. Consistent condom use remains the most effective way of preventing transmission of all sexual transmitted infections (STIs) including HIV. Condoms should be worn before penetration and used correctly with adequate water or silicone based lubrication.1
Men who have sex with men (MSM) are the group in the UK most affected by HIV (59 per 1,000 aged 15 to 59);3 however these statistics demonstrate that the vast majority of gay and bisexual men are not infected with HIV. Other high-risk groups are black Africans (65% of all heterosexual people living with HIV in the UK),3 people from other high risk countries (Russia, India and south east Asia), and individuals presenting with other sexually transmitted infections.
HIV infection can also be acquired via needle sharing (putting IV drug users at risk), infected blood products (very rare in the UK) and accidental needle-stick injuries. Overall this group make up a small percentage of those with HIV/AIDs in the UK.
HIV can be passed from mothers to their baby during birth or when breastfeeding. Transfer of the virus from mother to baby is rare in the UK due to routine screening of all pregnant women. Mothers found to be HIV positive are offered ART during pregnancy and special care around the time of delivery. In the UK HIV positive mothers are advised not to breastfeed due to the small risk of possible transmission of HIV in breast milk.
Clinical presentation
HIV may not cause symptoms for many years after a person becomes infected. During this time the person is able to pass on the virus to others although they are often unaware that they are infected.
The majority of patients (around 60%) do develop symptoms shortly after exposure to HIV. This is known as primary HIV infection (PHI) or seroconversion illness. It usually occurs two to six weeks following exposure. Symptoms of PHI are very non-specific; fever, sore throat, malaise, arthralgia, lymphadenopathy. Patients may also have a blotchy rash and orogenital or perianal ulceration.
Due to its non-specific nature PHI is easy to miss – especially within a primary care context. A high level of clinical suspicion is needed to risk assess those patients who do present to healthcare professionals during this time and offer them a HIV test as appropriate. The benefit of detecting patients at this stage is that they can then be offered ART very early in the course of infection which gives them the greatest possible chance of controlling viral load, and therefore not transmitting the virus to others.
Conditions associated with chronic HIV infection
As previously stated, individuals may remain asymptomatic for many years during which time the infection is difficult to detect clinically. Over time, as their immune system is compromised, individuals infected with the HIV virus become vulnerable to certain infections and cancers. The following are more common presentations:
1. Pneumocystis pneumonia (PCP) – this is a potentially life-threatening infection which may be difficult to detect in primary care. Symptoms usually progress slowly over several weeks. Presentation is a dry cough with shortness of breath and decreased exercise tolerance. Due to its potential severity any patient suspected of having PCP should be referred urgently to hospital for further tests.
2. Tuberculosis – more common in those with concurrent HIV infection and there is a greater propensity for this infection to be extra-pulmonary (ie not confined to the lungs) in patients with HIV.
3. Other chest infections – any community acquired chest infection is more common in immunosuppressed patients.
4. Neurological and visual symptoms – patients infected with HIV may present with a variety of neurological symptoms caused by infection or tumour growth. These include; headache, neck stiffness and photophobia, focal neurological signs, peripheral neuropathy, fits, confusion and memory loss.
5. Kaposi’s sarcoma – these are dark purple or brown lumps in the skin. They may look like bruises but feel harder. They may affect any area of skin and are also found in the mouth and in any part of the gastro-intestinal tract (see case study example).
6. Cervical cancer – any abnormality found on a cervical smear is more common in the presence of HIV infection.
7. Lymphoma – this will usually present with lymphadenopathy, fevers and night sweats. In the context of HIV infection, lymphoma may present atypically (for example cerebral disease) in which case it will present with focal neurological signs and headache.
8. Skin conditions – skin infections (fungal, viral or bacterial) may present in a more severe form or be harder to treat in the presence of HIV infection. Unusual or severe presentation of shingles may be seen – for example dermatomal shingles (ie affecting more than one dermatome).
9. Oral symptoms – oral candidiasis, aphthous ulceration, dental and gum problems may all be present and are signs of rising viral load.
10. Gastrointestinal symptoms – persistent diarrhoea may be a presenting feature of HIV infection.
Diagnosis and treating HIV and AIDS
Due to its long asymptomatic period and the multitude of different ways in which HIV infection can present, diagnosis can be a challenge. The most recent data suggests that a quarter of all of those living with HIV infection are unaware of their status, further highlighting the importance of increasing awareness among all clinicians across all sectors.
In response to this challenge, The British HIV Association (BHIVA) in 2008 released guidelines for HIV testing; the idea is to normalise HIV testing across a range of healthcare settings. Furthermore, they specifically recommend that in areas of high HIV prevalence (equal to and greater than two in 1,000 population) HIV testing should be routinely offered to all men and women registering in general practice.5 This advice was reiterated in NICE guidelines on HIV testing in black Africans and men who have sex with men (MSM) in 2011.6 The NICE guidelines are currently being reviewed and an update is expected7 in September 2016.
The 2008 BHIVA guidelines also highlight that all healthcare professionals should be able to obtain informed consent for HIV testing in the same way that they do for any other diagnostic test. Special counselling is not required, but it is important that consent is discussed – as you would in requesting any other test or investigation.
Types of HIV test
Testing for HIV infection can be carried out via laboratory testing, using a rapid point of care test (POCT) or self-testing. Current fourth generation laboratory tests give a positive result within four weeks of infection. If there is concern that the patient may have been exposed to HIV in the past four weeks, the test should be repeated in one month. A positive test result – otherwise known as a reactive test – should be repeated with a normal venepuncture sample. It is important that some of this information is provided prior to testing.4
POCT have the advantage that they provide an immediate result. However, they have a reduced specificity and sensitivity compared to current laboratory tests. There is an increased rate of false positive results, particularly in a low prevalence environment.5 All reactive results from a POCT need to be confirmed by laboratory testing. HIV self-testing has recently been allowed in the UK on the basis that access to testing should be encouraged for all the reasons highlighted earlier. Note that postal-testing is not the same – here the sample is collected by the individual and despatched for processing and the result in communicated via phone/text or letter. In self-sampling the sample is taken by the person, analysed with the testing kit and the result is almost immediate; this form of testing will not be suitable for everyone and sometimes it is more appropriate for an individual to be seeing a health professional for testing.
Management of HIV in primary care
Any patient found to have a positive HIV test in primary care needs to have this result repeated and should be referred immediately to the local HIV service. Specialist HIV clinics are able to offer confirmatory testing and full counselling services to help patients come to terms with their diagnosis. Management of HIV infection with ART is usually arranged through specialist HIV services. The aim is to keep viral load to a minimum and to maintain a CD4 count within normal range. Increasingly, HIV positive patients are receiving more of their routine care in primary care. It is therefore essential that primary care staff feel comfortable and confident managing HIV positive patients.
Conclusion
In conclusion HIV remains a significant public health problem within the UK with a high proportion of HIV positive individuals remaining unaware of their status. Routine HIV testing within primary care could help to reduce the stigma that continues to surround HIV infection and reach a larger population.
Resources
Terrence Higgins Trust – tht.org.uk
National AIDS Trust – nat.org.uk
AVERT – avert.org
HIV Aware – HIVaware.org.uk
References
1. Madge S, Matthews P, Singh S, Theobald N. HIV in Primary Care, An essential guide for GPs, practice nurses and other members of the primary care team. MedFASH; 2011.
2. Public Health England. United Kingdom National HIV surveillance data tables. No.1:2014 – New HIV & AIDS diagnosis & deaths, by year of diagnosis, year of death and sex. gov.uk/government/uploads/system/uploads/attachment_data/file/378078/National_tables_updated_19112014.xls (accessed 16 October 2015).
3. Public Health England. HIV in the United Kingdom: 2014 report. gov.uk/government/uploads/system/uploads/attachment_data/file/401662/2014_PHE_HIV_annual_report_draft_Final_07-01-2015.pdf (accessed 13 October 2015).
4. Rayment M, Asboe D, Sullivan AK. HIV testing and management of newly diagnosed HIV. British Medical Journal 2014;349: g4275.
5. British HIV Association, British Association of Sexual Health and HIVS, British Infection Society. UK National Guidelines for HIV Testing 2008. bhiva.org/documents/guidelines/testing/glineshivtest08.pdf (accessed 13 October 2015).
6. The National Institute for Health and Care Excellence. Increasing the uptake of HIV testing among black Africans in England (PH33). nice.org.uk/guidance/ph33. (accessed 13 October 2015).
7. The National Institute for Health and Care Excellence. Increasing the uptake of HIV testing among men who have sex with men (PH34). nice.org.uk/guidance/ph34 (accessed 13 October 2015).
