HIV

Overview

Infection with HIV causes chronic immune deficiency which, if untreated, leads to acquired immunodeficiency syndrome (AIDS) after a variable period but on average 10 years after infection.
HIV infection is treated by combination antiretroviral therapy (ART) which is life-long.
Current evidence suggests that all people living with HIV should start ART as soon as possible after diagnosis.
All patients need regular monitoring visits to assess their immune status, to check on response to therapy and to provide psycho-social support.

Cause

Infection with human immunodeficiency virus (HIV), a single-stranded RNA virus.

Clinical presentation

Symptoms

Acute infection: (in 70% of patients) fever, rash, lymphadenopathy, pharyngitis, myalgia, diarrhoea, about 2 weeks after exposure

Asymptomatic infection: for several years following infection

Immune deficiency: multiple symptoms related to declining CD4 T-cell count such as oral thrush, diarrhoea, weight loss, skin infections, herpes zoster

Complications

AIDS: opportunistic infections such as Pneumocystis (carinii) jiroveci pneumonia, oesophageal candidiasis, cerebral toxoplasmosis and cancers such as Kaposi’s sarcoma

Diagnosis

Decision making tool for HIV

Test	Site/Specimen	Consideration
HIV Ag/Ab	Blood	Usually lab will perform a combination HIV Ag/Ab test, usually reactive within 6 weeks of infection but occasionally longer
Western blot	Blood	Confirmatory test
HIV p24 antigen	Blood	High during HIV primary illness
CD4 lymphocyte	Blood	Marker of immune function, usually >500
HIV RNA (viral load)	Blood	Maker of HIV level in serum, should be undetectable if on treatment
HIV point of care test	Blood/saliva	Point-of-care testing with result in 10– 20 minutes but less sensitive or specific than standard test
HIV Ag/Ab – Human immunodeficiency virus antigen/antibody

Investigations

Multiple investigations are recommended for the newly diagnosed patient with HIV including CD4, HIV viral load, standard biochemistry, glucose, lipids, urinalysis, and hepatitis A, hepatitis B and hepatitis C serology. Consider screening for tuberculosis.
Test for HIV genotype and drug resistance assay as the earliest blood sample will provide the most accurate result.

Management

See the Antiretroviral Guidelines for more information about treatment options.

Treatment advice

Patients will need considerable advice and support regarding the long-term nature of therapy and the importance of good adherence. See the Antiretroviral Guidelines for more information.

Other immediate management

Discuss complex issues around HIV transmission, need to inform sexual contacts of HIV status and contact tracing
For the asymptomatic, newly diagnosed patient, consider psychosocial support and avoid over-emphasis of technical discussions about treatment options in the initial discussion
May need urgent referral to experienced psychologist
Consider testing for other STIs, if not undertaken at first presentation, or retesting post the window period.
Provide patient with fact sheet
Notify the state/territory health department.

Special treatment situations

Special considerations

Patient unwell consider urgent referral to hospital or specialist centre for assessment.
All complex situations should be managed in collaboration with a specialist.

Situation

Recommended

Co-infection with hepatitis B or hepatitis C

May need to modify treatment choice. Seek specialist advice

Pregnant women

Should start ART – complex. Seek specialist advice

Allergy to treatment

Check HLAB57 status prior to use of abacavir

HIV primary illness

Urgent commencement of ART

CD4 <200

High risk for opportunistic infection needs urgent treatment. May need chemoprophylaxis with co-trimoxazole/fluconazole - seek specialist advice.

ART – Antiretroviral therapy

Contact tracing

Notifiable condition
Start with recent sexual or needle-sharing partners; outer limit is onset of risk behaviour or last known negative HIV test result if known
Post-exposure prophylaxis (PEP) can be offered within 72 hours of potential HIV exposure. See the National HIV PEP Guidelines and Policy for more information.
Pre-exposure prophylaxis (PrEP) is an important new prevention option and can provide highly effective biomedical prevention of HIV in HIV-negative individuals. See the National PrEP Guidelines for more information.

See Australasian Contract Tracing Manual - HIV for more information.

Follow up

Close follow-up recommended after diagnosis, within a few days to check on psychosocial well-being and to review baseline investigation.
Patient will need long-term regular reviews by practitioner experienced in HIV care, via specialist clinic, sexual health service or section 100 GP.
Patient should also see GP for ongoing general care.
Once stable on antiretroival therapy follow-up can be every 3-6 months.

Auditable outcomes

• 100% of patient should have contact tracing performed.
• 100% of patients should be offered treatment at the time of diagnosis.

Last Updated: Wednesday, 11 July 2018

HIV