Resistance Testing Recommendations
The following clinical areas of need have been identified by the International AIDS Society – USA Panel (IAS/USA):
Summary of Clinical Situations in which Resistance Testing is Recommended
| Acute or Recent HIV Infection | Before Initiation of Antiretroviral Therapy in Established HIV Infectionb |
|---|---|
| Acute infectiona | Patients infected within previous 2 years and possibly longer |
| HIV infection within previous 12 months (if known) | First regimen failure |
| Suboptimal HIV-1 RNA response to therapy | Multiple regimen failure |
| Pregnancy if mother has detectable plasma HIV-1 RNA level |
a: Therapy should not be delayed for resistance testing results.
b: In untreated, established infection, wild type isolates may replace drug resistant quasi species over time.
The European Resistance Testing Recommendations published in AIDS suggest the following clinical indications:
| Clinical Characteristics | Recommendation |
|---|---|
| Treatment naïve patients, (primary infection/recent infection) | Consider testing (not used in the previous table). Test for resistance if reasons to suspect transmission from a treated individual exist and treatment is to be initiated. |
| Chronic infection | Consider testing for resistance if transmission rate is high or reasons to suspect transmission from treated individual exist. |
| Post-exposure prophylaxis | Do not delay treatment due to resistance testing, but if sample from the index case is available, test and treat accordingly. |
| Treated patients | Test for resistance in all cases where changes. |
| Pregnancy | Test for resistance if the mother has a detectable virus load. |
| Pediatrics | Test for resistance in HIV-1 infected children born to mothers on treatment with detectable viremia and consider testing in children with virologic treatment failure. |