Use of Drug-level Testing and Single-genome Sequencing to Unravel a Case of Human Immunodeficiency Virus Seroconversion on Pre-exposure Prophylaxis

Clin Infect Dis. 2021 Jun 1;72(11):2025-2028. doi: 10.1093/cid/ciaa1011.


Cases of seroconversion on pre-exposure prophylaxis (PrEP) should be carefully investigated, given their public health implications and rarity. We report a case of transmitted drug resistance causing seroconversion on PrEP in spite of high adherence, confirmed with dried blood spot and segmental hair drug-level testing and single-genome sequencing.

Keywords: HIV seroconversion; PrEP; PrEP failure; adherence; single-genome-sequencing.

Publication types

  • Case Reports
  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Anti-HIV Agents* / therapeutic use
  • Emtricitabine / therapeutic use
  • HIV
  • HIV Infections* / drug therapy
  • Humans
  • Medication Adherence
  • Pharmaceutical Preparations*
  • Pre-Exposure Prophylaxis*
  • Seroconversion
  • Tenofovir / therapeutic use


  • Anti-HIV Agents
  • Pharmaceutical Preparations
  • Tenofovir
  • Emtricitabine