Infectious diseases clinical outcomes

Clinical outcomes are measurable changes in health, function or quality of life that result from our care. Constant review of our clinical outcomes establishes standards against which to continuously improve all aspects of our practice.

About the Infectious diseases service

The Infectious diseases department provides clinical expertise in the diagnosis and management of unusual and complicated infections, tropical diseases, and children with Human Immunodeficiency Virus (HIV) infection. There are also specialist clinics for children with tuberculosis and chronic viral hepatitis. A large part of our work is around antimicrobial stewardship, a process which ensures that medicines used to treat infections are used in the best possible way across the hospital. One of the main elements of our outpatient service is dedicated to the care of HIV infected children. The following section details clinical results for this service for which we have robust local and national data.

Clinical outcome measures - HIV

HIV is a virus which attacks the body’s immune system and weakens its ability to fight infections and diseases, such as cancer. It is a life-long condition that can lead to acquired immunodeficiency syndrome (AIDS), where the body’s immune system can no longer fight infections and tumours.

While there is no cure for HIV, medication known as antiretrovirals works by slowing down the damage the virus does to the immune system. The outlook for children with HIV in Britain today is very good, a lot better than it was even 10 to 15 years ago. HIV is now considered a chronic life-long condition that must be controlled. There is evidence of this within the service at GOSH, where children in their teens are well and show every likelihood of living into their thirties and beyond. Only one child under the care of the HIV clinic at GOSH has died with AIDS at GOSH in the last five years, in comparison to 13 deaths in 1996 alone.

The HIV team provide regular medical monitoring of every patient with HIV to see how the virus is affecting his or her health and how effective medication is. This involves a number of tests and examinations.

1. CD4 cell count results

One of the most important tests used by the team is called a CD4 cell count. HIV attacks CD4 cells in the immune system. A CD4 cell count measures the number of CD4 cells in a sample of blood to give a rough idea of the health of the patient’s immune system. The higher the count, the better the immune system.

The CD4 cell count can vary from 0 to over a 1000 per cubic milliliter of blood. A lower CD4 count can be a sign that HIV is progressing, and the immune system is becoming weaker. If CD4 cell count levels reduce to less than 350 per cubic milliliter then the immune system may not work optimally.

For children aged five and over looked after at GOSH the vast majority of patients have a CD4 count greater than 350 cells per cubic milliliter (97%). This is a slightly higher proportion than that reported nationally (93%).

Fig 1.1 CD4 count for children aged five and over followed up since 2017, by treatment status¹

Figure 1.1 CD4 count for children aged five and over followed up since 2017, by treatment status

¹ ART – antiretroviral therapy

2. Viral load results

Another important marker of the management of HIV is viral load, which is a test to determine the level of HIV in the body. The quantity of virus is measured in 'copies per ml' of blood. The lower the number, the less active virus is present. The treatment aim is to maximally suppress the virus (viral load equal to or less than 50 copies per ml) to help the CD4 count to normalise. Normalisation of CD4 counts means that children are less likely to become unwell or get serious infections.

The line chart and table below show the percentage of GOSH patients and the percentage of total paediatric patients across UK and Ireland who have a viral load of equal to or less than 50 copies per ml, 12 months after starting combined Anti-Retroviral Therapy (cART). 

Fig 2.1 Percentage of patients with a viral load of equal to or less than 50 copies per ml 12 months¹ after starting cART naïve²

Figure 2.1 Percentage of patients with a viral load of equal to or less than 50 copies per ml 12 months after starting cART naïve

Table 2.1 Percentage of patients with a viral load of equal to or less than 50 copies per ml 12 months¹ after starting cART naïve²

Years GOSH UK & Ireland
2000 to 2004 21/43 (49%) 125/300 (42%)
2005 to 2009 37/53 (70%) 275/435 (63%)
2010 to 2014 27/28 (96%) 224/299 (75%)
2015 to 2019 17/23 (74%) 91/116 (78%)

¹ Response is based on the viral load value nearest 12 months (+/-3 months) after cART initiation

² Defined as: first combination ART composed of 3 or more drugs across two classes (excluding unboosted Protease Inhibitor (PI), or three nucleoside reverse transcript inhibitors (NRTIs) including Abacavir (ABC)).

For children followed up since 2017, the latest data from GOSH shows that 84% (n = 56/67) of children on antiretroviral therapy have an HIV load equal to or less than 50 copies per ml of blood. This is similar to the national equivalent figure which is 86% (n = 531/615). 

3. Health status at point of transition to adult care

Over the last few years an increasing number of young people from GOSH HIV clinic have moved on (transitioned) to adult HIV services. Guidelines on antiretroviral therapy have evolved over the years meaning that it is now recommended that all children are started on antiretroviral therapy rather than waiting for a problem with their health or drop in their CD4 count.

We have always aimed for health status to be optimised during childhood and at the time of transition. The proportion of young people with an undetectable HIV viral load and CD4 count higher than 350 cells per cubic milliliter has increased year on year in part due to change in guidelines but also as a direct result of improvements in the range of antiretrovirals available to young people.

Since 2015, the proportion of young people transitioning to adult care with an undetectable HIV viral load is 69% (national proportion is 72%), and the proportion with a CD4 count higher than 350 cells per cubic milliliter is 90% (national proportion is 87%).

Fig 3.1 Viral load at last visit in paediatric care prior to transfer to adult care

Figure 3.1 Viral load at last visit in paediatric care prior to transfer to adult care

Fig 3.2 CD4 cell count at last visit in paediatric care prior to transfer to adult care

Figure 3.2 CD4 cell count at last visit in paediatric care prior to transfer to adult care

About the information

Anonymous information is submitted to the Collaborative HIV Paediatric Study (CHIPS) database for national comparison. This information was provided by the Collaborative HIV Paediatric Study and GOSH reports are published annually.

This information was published in June 2019 and will be updated in June 2020.