Worked teaching cases
Open a case to see it in the decision tool, change the inputs and watch the recommendation respond. The learning points appear at the top of the report.
Starting ART: an uncomplicated first presentation
first-lineINSTIA 31-year-old man diagnosed at a sexual health clinic. HIV RNA 48,000 copies/mL, CD4 520. HBsAg negative, HLA-B*57:01 negative, baseline resistance test shows no mutations.
Learning points
- BHIVA preferred first-line options are an INSTI (bictegravir or dolutegravir) with two NRTIs, or dolutegravir/lamivudine when HBV, resistance and high viral load have been excluded.
- Single-tablet regimens are favoured for convenience but are not more effective than multi-tablet ones.
- Check the SmPC §4.5 of the chosen regimen against every co-medication, including over-the-counter antacids and supplements (cation chelation with INSTIs).
Hepatitis B co-infection with chronic kidney disease
HBVrenalA 58-year-old man, HBsAg positive, creatinine clearance 42 mL/min, type 2 diabetes on metformin, on atorvastatin. HIV RNA 120,000 copies/mL, CD4 310.
Learning points
- HBV co-infection needs tenofovir plus emtricitabine or lamivudine — dual-therapy and abacavir backbones do not treat HBV adequately.
- Below CrCl 50 mL/min tenofovir disoproxil combinations should not be started (Delstrigo, Eviplera SmPC §4.2); tenofovir alafenamide combinations remain usable down to 30 mL/min.
- Dolutegravir raises metformin exposure (SmPC §4.5) — adjust and monitor.
Newly diagnosed in pregnancy
pregnancyA 27-year-old woman at 14 weeks' gestation found to have HIV at antenatal screening. HIV RNA 30,000 copies/mL, CD4 450, HBsAg negative.
Learning points
- Dolutegravir-based ART is preferred in pregnancy; the early neural-tube-defect signal was not confirmed in larger datasets.
- Cobicistat-boosted regimens are not recommended in pregnancy — exposures fall in the second and third trimesters (Symtuza, Rezolsta SmPC §4.6).
- BHIVA recommends monitoring HIV RNA through pregnancy and planning delivery around the 36-week viral load.
Advanced HIV with tuberculosis on rifampicin
TBinteractionsA 35-year-old man with pulmonary TB, started on rifampicin-based treatment 10 days ago. CD4 85, HIV RNA 250,000 copies/mL. Resistance test pending.
Learning points
- Rifampicin is contraindicated with bictegravir, rilpivirine, doravirine, cabotegravir and boosted PIs (SmPC §4.3), and BHIVA advises against cobicistat with any rifamycin.
- BHIVA's TB guideline puts efavirenz with tenofovir disoproxil/emtricitabine first line on rifampicin, with dolutegravir (50 mg twice daily) or raltegravir as alternatives, and advises against TAF- or bictegravir-containing combinations and two-drug regimens until outcome data exist.
- ART within 2 weeks of TB treatment if CD4 < 50, otherwise within 4 weeks of the TB diagnosis; CNS TB is the exception and can be delayed for 8 weeks. Watch for paradoxical TB-IRIS.
Virological failure on an NNRTI regimen
resistancefailureA 41-year-old woman on efavirenz/emtricitabine/tenofovir disoproxil since 2019, suppressed until 2025; HIV RNA now 15,000 copies/mL. Resistance test: RT K65R, M184V, K103N.
Learning points
- K65R reduces tenofovir and abacavir activity but increases zidovudine susceptibility; M184V makes lamivudine/emtricitabine only partly active.
- A fully active, high-barrier anchor (dolutegravir or boosted darunavir) is the priority after failure; trials such as NADIA showed recycled tenofovir/lamivudine works with dolutegravir.
- Address adherence, interactions and tolerability before switching — and always act on a genotype taken on the failing regimen.
Switching to long-acting injectable therapy
switchlong-actingA 29-year-old man suppressed for 3 years on Biktarvy, no previous failure, HBsAg negative and HBV-immune, who would prefer not to take daily tablets.
Learning points
- Cabotegravir + rilpivirine long-acting is for adults who are virologically suppressed with no known or suspected resistance to NNRTIs or INSTIs (Vocabria and Rekambys SmPC §4.1; BHIVA 2025 §5.11; NICE TA757).
- Injections every 2 months, gluteal IM, with an optional oral lead-in; missed injections need an oral bridging plan. BHIVA advises 2-monthly viral loads for the first 6–12 months.
- BHIVA 2025: high BMI alone does not reduce efficacy, but avoid the combination of BMI > 30 kg/m² with HIV-1 subtype A6; rilpivirine resistance mutations are a contraindication.