Clinical follow-up and monitoring of patients on PrEP
Any positive HIV test result should be managed urgently by appropriate counselling and referral to an HIV prescriber. Assistance can be sought via telephone from a local sexual health clinic. It is very important for the clinician to recognise that HIV acquisition in a person who is using PrEP is a highly significant event and that the emphasis should be on supporting the person initially rather than focusing on how the infection occurred. If a patient is diagnosed with HIV infection while taking PrEP, their current health and wellbeing should be the chief immediate priority as opposed to enquiries about their adherence to PrEP.
Acute HIV infection should be suspected in people at risk for HIV who were not taking PrEP at the time that they were recently exposed to HIV (e.g. no condom, or a condom broke during sex with an HIV-positive partner who was not on antiretroviral treatment, or has a detectable HIV viral load; condomless anal sex with a casual partner; recent injecting drug use with shared injection equipment with an HIV-positive partner). Also, infection with tenofovir disoproxil* (TD*)- and/or emtricitabine (FTC)-resistant HIV is possible, however, it is very uncommon while on PrEP, with only a few cases reported internationally (3). Therefore, in addition to sexual behaviour and injecting drug use, clinicians should elicit a history of any signs and symptoms of viral infection during the preceding month, including the day of PrEP evaluation. See the Table for clinical symptoms and abnormalities of acute (primary) HIV infection.
In this setting HIV drug resistance testing should be performed in all cases and if the patient reports high PrEP adherence they may agree to have their blood, and hair tested for tenofovir and emtricitabine drug levels. In this setting urgent referral to an HIV specialist is recommended. If urgent review by an HIV specialist is not possible, then the diagnosing clinician may wish to phone ASHM who will be able to help coordinate the patient and a clinical advisor.