An estimated 39% of human immunodeficiency virus (HIV) diagnoses in Australia are made late, defined as a diagnosis with a CD4 T-lymphocyte (CD4) count of less than 350 cells/µL, and about 20% of these are advanced infections, defined as having a CD4 count of less than 200 cells/µL.
People diagnosed late (sometimes referred to as late presenters) may learn of their HIV status after being diagnosed with an opportunistic illness or infection such as Pneumocystis jirovecii pneumonia or central nervous system infections such as cerebral Toxoplasmosis gondii infection.  (see also Clinical manifestations of HIV disease). They are more likely to require intensive care support if hospitalised, experience lengthy hospitalisation and have an increased risk of acquired immune deficiency syndrome (AIDS) or death particularly in the first year after diagnosis.   Lengthy hospitalisation can leave the patient fatigued, deconditioned and psychologically vulnerable. When starting HIV therapy, those who have been diagnosed late generally experience a longer time to immune reconstitution, are at prolonged risk of opportunistic infections and may also experience immune reconstitution inflammatory syndrome (IRIS).
Early HIV diagnosis and treatment, on the other hand, offers benefits including reduced morbidity and mortality, avoidance of inpatient care, prevention of HIV transmission and better quality of life through appropriate treatment, care and support. Nurses working in a wide range of settings - sexual health, viral hepatitis and HIV, primary care, community health, the drug and alcohol sector and homelessness services - can have an important role to play in increasing awareness and access to HIV testing for vulnerable groups and in promoting HIV testing with appropriate pretest education to avoid late diagnoses.
Strategies are in place in Australia to promote early diagnosis and treatment initiation. These include HIV testing during antenatal screening and regular sexually transmissible infection (STI) screening for men who have sex with men. However, there are gaps in reaching those who may not perceive themselves as being at risk of HIV infection: for example, older adults, women and heterosexual males. Nurses working in community health and primary care can assess risk and offer testing for HIV infection in individuals who present for general age-related medical examinations such as women attending for cervical cancer screening (Pap tests). Nurses involved in the development of Medicare-funded care plans can introduce questioning around relationships and sexual health, especially in older adults disclosing high-risk behaviours and those with unexplained illnesses.
Barriers to testing and reasons for late diagnoses
In Australia, HIV infections are mainly diagnosed in people who have engaged in an identifiable risk behaviour (such as men who have sex with men). However significant rates of infection are being diagnosed in women, people from culturally and linguistically diverse (CALD) backgrounds and people in older age groups.  Personal and health-care provider ignorance about risk, social isolation, poor access to health care, language and cultural barriers, HIV-related stigma and fear of discrimination are some factors which prevent people from having timely HIV testing. Regular HIV testing is often not the norm among groups who do not perceive themselves as at risk for HIV and it has been reported that testing in some cases is motivated only by a serious health crisis.
While late presenters have often had limited contact with health services before their HIV diagnosis, in some cases a person may have presented to primary health services with potential HIV-related signs and symptoms e.g. seborrhoeic dermatitis, oral candidiasis or unexplained weight loss, but the diagnosis has been missed. This can be because the attending health-care worker does not have the knowledge to consider HIV as a possible cause and does not identify risk factors for HIV infection.
Nursing implications of late diagnosis - severe disease, treatment and prevention of opportunistic illnesses
Where people have been diagnosed late with HIV infection, skilled nursing is essential to the patient’s ability to follow through with treatments and remain engaged with the health system. The opportunistic illnesses (referred to as AIDS-defining illnesses or AIDS indicator diseases) with which those diagnosed late and with advanced disease may present are nowadays relatively rare. Nurses in low HIV prevalence settings such as Australia are therefore less likely to have first-hand experience and knowledge of such illnesses. Thus, it remains important for nurses to understand the natural history and management of HIV and opportunistic illnesses.
Nurses play a key role in supporting people who are diagnosed late, with the capacity to spend greater amounts of direct and indirect time with clients than other health professionals. Psychological and emotional reactions to a new HIV diagnosis can vary and can be serious (see Section 1 New diagnosis of HIV). The client may display signs of depression, appear withdrawn or become completely overwhelmed. Nurses can identify signs of difficulty with adjusting to and managing illness and intervene. They can support the client by listening, giving clients time to talk through their problems, providing empathy and care, and emphasising to the client that he or she is not alone. Utilising resources such as written information, audio visual aids and peer support (meeting other HIV-positive people) can help ease the adjustment process. These interventions are all useful to promote engagement and retention in care.
Nurses can educate clients, family members and other disciplines alike about specific issues to be aware of during this period; for example, signs of anxiety and depression; barriers to care, signs of disengagement; signs and symptoms of new opportunistic illnesses; difficulty with adherence to medication and treatment toxicities or adverse reactions (see also Therapeutics and monitoring).
Primary health and community nursing services that are well integrated with peer support agencies and volunteer based services can be fundamental to supporting the emotional and social adjustment of those diagnosed late and who have advanced disease.
People hospitalised following late diagnosis and illness are often discharged with multiple medicines. In addition to antiretroviral therapy (ART) to reduce HIV viral load and improve immune function, they may require medicines to treat opportunistic infections and others to reduce the risk of other opportunistic infections developing while their CD4 count is low (below 200 cells/μL). This entails a significant pill burden, which is recognised as a barrier to adherence.  
Managing multiple medicines can be difficult, especially for clients who have never taken these medications before. Nurses can assess, assist, and supervise medication management. High, sustained levels of adherence to ART (over 95% of all prescribed doses taken) maximise its effectiveness, reduce the chance of new or recurrent illness, reduce short- and long-term mortality and prevent the onward transmission of HIV. Of equal importance is adherence (doses taken and completion of the prescribed course) to medicines prescribed to treat opportunistic illnesses and the sustained use of those used to prevent new opportunistic infections (See Clinical manifestations of HIV disease)). Nurses also have a key role in educating clients about and monitoring for side-effects. (See Section 11 Adherence support for more details).
HIV-related stigma remains very real for many people. Inadvertent disclosure of a person's HIV status can have serious consequences for the person with HIV. Therefore, special care needs to be taken. Respect for people's privacy and confidentiality is essential and should be actively communicated. Strategies such as providing a locked box to store medicines and medical documentation about the person’s treatment and condition can help maintain privacy and confidence.
Access to and retention in HIV specialist clinical care, and safe medicine administration delivered by qualified and competent professionals underpin increased survival for people with HIV. People diagnosed late should have access to the assistance of community nurses upon discharge from acute services and referral should be made early, even where an obvious nursing clinical procedure is not needed. Close collaboration and liaison between hospital- or clinic-based nurses, nurses in primary care and community nursing services are essential and are a strong feature of the HIV sector in Australia (see also Section 15 Evolving roles of nurses in HIV care).
Late presenters and the risk of immune reconstitution inflammatory syndrome
Effective ART stimulates immune reconstitution, reducing the risk of opportunistic illnesses. However, some people commencing ART experience a phenomenon referred to as immune reconstitution inflammatory syndrome (IRIS) that can be life-threatening.
Most people who develop IRIS will do so within 90 days of starting ART, though it can appear as early as 1 week and as late as 1 year after the person starts treatment. People are at greater risk with CD4 counts below 200 cells/µL and high viral loads.
IRIS can manifest in two ways:
- Paradoxical IRIS: ART initiation (in an ART-naïve patient) in the presence of a known but treated opportunistic illness (OI) may worsen the OI despite improvement in the overall immune function. For example, a person may have been treated for cryptococcal meningitis, then commence ART and re-develop symptoms such as headache, necessitating re-treatment of the cryptococcal infection.
- Unmasking IRIS: a previously unrecognised OI can become clinically evident as immune function improves. For example, a person may be discharged home from hospital feeling well after starting ART, then begin to have night sweats, joint pains and loss of weight and be diagnosed with an OI such as Mycobacterium avium complex infection 2 months later.
Treatment of IRIS depends on the clinical presentation and the particular OI involved, but generally entails the use of corticosteroids and/or non-steroidal anti-inflammatory medicines.
An IRIS event may be serious enough to require hospitalisation. Early referral to community-based or visiting nurses is useful as they are well placed to observe and identify symptoms of an IRIS event and expedite prompt medical attention. Nurses working in HIV can be an important link in the identification of IRIS and must have an awareness of IRIS as a possible complication of ART initiation so that appropriate action can be taken. Antiretroviral guidelines suggest parameters regarding CD4 counts in the presence of an opportunistic infection to help prevent IRIS events (see arv.ashm.org.au). Nurses can educate and support people to remain on treatment if IRIS develops, and in the management of side-effects and symptoms of IRIS.