Monitoring antiretroviral therapy for HIV infection

Patients taking antiretroviral therapy require careful monitoring. Review patients 2 to 4 weeks after starting treatment, then every 3 to 4 months if stable. The interval between reviews can be extended to 6 months for adherent patients with suppressed viral load who are clinically and immunologically stable for more than 2 years.

Monitor:

• clinical status and treatment adherence – some patients may need the support of a multidisciplinary team
• HIV viral load – the viral load should fall at least 10-fold 4 to 6 weeks after starting antiretroviral therapy, and to below 50 copies/mL after 3 to 6 months. Once the viral load has fallen below the level of detection, measure the viral load every 3 to 6 months
• CD4 cell count
  • check the CD4 cell count 3 months after starting antiretroviral therapy, then every 3 to 6 months; the count usually increases by 100 to 200 cells/microlitre after 12 months
  • for patients with a suppressed HIV viral load and a CD4 count more than 200 cells/microlitre for 2 years or longer, measure less frequently (eg every 12 months)Girard, 2013
  • for patients with a suppressed HIV viral load and a CD4 count more than 500 cells/microlitre, further CD4 cell count monitoring is optionalChow, 2015Gale, 2013Girard, 2013
• toxicity of antiretroviral therapy
  • check full blood count, serum electrolytes, creatinine and liver biochemistry at each scheduled visit, if indicated¹
  • recheck the creatinine level 4 weeks after starting drugs that affect creatinine secretion (eg bictegravir, cobicistat, dolutegravir, rilpivirine) to establish a new baseline creatinine
  • in patients taking tenofovir, check serum creatinine, urine protein-to-creatinine ratio, glycosuria and serum phosphate every 3 months for the first year. Following this, in people without kidney disease or risk factors for kidney disease, testing frequency can be reduced to 6 to 12 monthly
  • consider whether abnormalities could be due to antiretroviral therapy, other drugs or disease
• risk factors for cardiovascular disease²
  • address behavioural risk factors (smoking, diet, exercise – see Overview of modifiable lifestyle risk factors for atherosclerotic cardiovascular disease)
  • monitor blood pressure and weight regularly
  • monitor blood glucose and lipid levels before and 3 to 6 months after starting therapy, and then every 12 months, or more frequently if abnormal
• risk factors for osteoporosis – assess risk factors and manage accordingly (see Osteoporosis and minimal-trauma fracture)
• risk of cervical cancer – regularly screen all people with a uterus and HIV infection for human papillomavirus.

Therapeutic drug monitoring for antiretroviral therapy is rarely indicated. For further information, see the Australasian Society for HIV, Viral Hepatitis and Sexual Health Medicine website.