Contents
- Stages and symptoms of HIV
- Who is getting infected?
- Antiretroviral Therapy
- Treatment better in UK
- Conclusion
Introduction
HIV continues to be an important communicable disease in the UK. It is an infection that is associated with serious illness and death, high cost of treatment and high numbers of potential years of life lost. Nevertheless, treatment advances over the last fifteen years following the introduction of highly active antiretroviral therapy has resulted in large reductions in AIDS incidences and deaths in the UK. However, many patients with HIV infection currently remain undiagnosed unfortunately, which means that they are not receiving treatment and support which could improve their health but also significantly reduces the chance of them transmitting the virus to their partners. It is to this group that we need to direct our energies as, despite increased levels of testing leading to an increase in the prevalence of diagnosed infections, the prevalence of undiagnosed infections has not changed significantly over the last ten years.
Over 20,000 people in the UK are unaware of their infection.
The number of people with HIV in the UK was estimated in the last report from the Health Protection Agency to be 86,500 with 26% of these are people unaware of their infection.
So:
- How would someone know that they should be tested for HIV infection?
- What are the symptoms/lifestyle risks that could alert a patient to the fact that they might have HIV infection? Or conversely, reassure them that they are unlikely to have HIV infection?
- Where/who are these 20,000 people who do not know that they are infected?
Stages and symptoms of HIV
The key stages of HIV infection are as follows:
- Primary HIV infection
- Chronic asymptomatic infection
- Symptomatic HIV infection
- AIDS defining condition
Symptoms of HIV
The symptoms vary and depend on the stage and type of an infection.
Primary HIV Infection (Seroconversion)
Primary HIV infection is classically described as an acute glandular fever type illness occurring 2–6 weeks after infection. It normally lasts for one or two weeks, may be considerably longer in a few patients and for many patients may pass unnoticed.
The main symptoms are as follows:
- Fever
- Lymphadenopathy
- Arthralgia
- Myalgia
- Anorexia
- Weight loss
- Diarrhoea
- Rash
- Oral ulceration
The combination of symptoms of fever, maculopapular rash and lymphadenopathy are the most common.
The diagnosis is dependent on the demonstration of HIV antibodies or in the absence of antibodies on HIV-1 RNA quantification.
Chronic Infection
Following acute HIV infection a viral set point which is governed by the unique immune response of the hosts of the virus is reached and patients enter the phase of chronic HIV infection.
During this time there is a steady reduction in CD4 cells and towards the end of this phase patients may begin to experience constitutional symptoms and develop illnesses referred to as indicator diseases. The rate of CD4 decline is very variable with a small minority never progressing to AIDS, for example in long term non-progressors, while other patients may progress more rapidly. With progressive loss of CD4 cells the patient may develop the relatively common symptoms of weight loss, neurocutaneous disease including severe dermatitis, recurrent oral ulceration, and herpes zoster as well as upper respiratory tract infections.
As the disease progresses and the CD4 declines further, the patients may develop chronic fever, unexplained fever, oral candida, oral leukoplakia and severe bacterial infections. Finally with advanced disease where the CD4 drops below 200 cells/mm3 patients are at risk of the AIDS-defining opportunistic infections which include PCP (a form of pneumonia), cerebral toxoplasmas, CMV disease and the HIV related tumours such as lymphoma and Kaposi’s sarcoma.
Who is getting infected?
The newly infected – increasing numbers of new diagnoses reflect the increased levels of HIV testing but many patients are not diagnosed for years after they were infected. However, the Health Protection Agency does try to estimate how many new infections are occurring in the UK and they estimate that there are 3000 new infections among men who have sex with men (MSM) each year and that a quarter of newly diagnosed MSM in 2010 probably acquired their infection in the few months prior to diagnosis. In heterosexual men and women there was estimated to be at least 300 to 400 new infections last year.
The groups at highest risk for HIV in the UK are MSM and people from black African communities; however these are not the only ones at risk. There are increasing numbers of people who have acquired their infection through heterosexual sexual contact in the UK. The other main routes of transmission are in sharing needles and syringes and mother to child transmission, however, in the UK these fortunately make up a very small proportion of cases with very few babies being infected in utero.
Although HIV infection is a problem across the UK there is a particularly large concentration of cases in London with more than 40% of infections reported in London residents.
Antiretroviral Therapy
Prognosis has improved immeasurably for patients with HIV infection in the UK and this is related to highly active antiretroviral therapy. We now have 24 licensed antiretroviral agents with drugs from a number of classes. These include the nucleoside reverse transcriptase inhibitors, the non-nucleoside reverse transcriptase inhibitors, protease inhibitors, integrase inhibitors and CCR5 antagonists/entry inhibitors. All the drugs work by interfering with viral replication, some drugs are co-formulated and it is now usual for patients to be on a simple regimen of once, or at most twice, daily treatments.
Another very significant advance in the management of patients with HIV infection has been the availability of genotypic resistance tests which have identified transmitted and acquired resistance and enabled clinicians to make the optimal drug choices for an individual when starting therapy and when patients develop virological failure. Many of the drugs do have both short- and long-term toxicities and given the number of drugs available regimens can be changed to one that is optimal for an individual patient.
Treatment better in UK
The quality of HIV care in the UK is high and comparison with data from the US shows that treatment is superior in the UK. Based on London data, 80% of newly diagnosed patients were seen in an HIV clinic within one month of diagnosis. One year after starting therapy 90% had an undetectable viral load (less than 50 copies per ml) and 93% of those receiving care for more than a year had a CD4 count of over 200 cells per mm3. The uptake of HIV testing in antenatal clinics is very high with 95% having an HIV test, which has led to very small numbers of children being infected by mother-to-child transmission. In sexually transmitted infection clinics 77% of attendees in England agree to HIV testing.
In my clinic at the Royal Free Hospital there are approximately 3,000 patients receiving care. Around 38% acquired their infection heterosexually and approximately 30% are female. In 1993 there were 10.7 deaths per 100 patient-years and by 2008 this had fallen to 2 events per 100 patient-years. There were 28 AIDS events per 100 patient-years in 1992 which had fallen to 2.3 events per 100 patient-years by 2008. This has resulted in a dramatic reduction in hospitalisations with 38.1 hospitalisations per 100 patient-years in 1992 falling to 4.6 hospitalisations per 100 patient-years in 2008. The average CD4 cell count at the Royal Free of our patient clinical population was 290 cells per mm3 and by 2008 this had risen to 520 cells per mm3.
To put this in another way, anyone diagnosed with AIDS now, compared to twenty years ago, can expect both a more successful chance of life, as well as an improved quality of life.
Conclusion
We have become increasingly aware that for many patients infected with HIV an important factor is the management and treatment of the long-term consequences of the infection itself and the long-term toxicities of antiretroviral therapy. These include increased cardiovascular risk, osteoporosis, renal disease, an increase in non-AIDS related cancers and neuro-cognitive disorders. It is essential that patients with HIV infection are looked after by physicians experienced in the management of this chronic infection.
I finally want to end on a plea for doctors in the UK to think about HIV infection in both general practice and secondary care. As discussed earlier, late diagnosis remains a considerable cause of serious illness and death and it is essential that HIV antibody testing is recommended by doctors when patients see them with clinical problems that could be related to HIV infection. The days when an HIV test needed individual counselling are gone. Any healthcare professional should be able to offer this to their patients when clinically indicated in high prevalence areas (greater than 2/1000 diagnosed with HIV infection). The routine offer and recommendation to accept an HIV test for all adult general practice patients and general medical admissions should be implemented.
