Today I saw a patient who was infected with HIV in the 1970s and is alive today. In the modern era of HIV treatment in the US, seeing people survive long term with HIV is commonplace. In fact, it is projected that in a few years individuals over 50 will comprise half the cases in the US (as I was quoted saying in this article).
The interesting thing about this patient, however, is that the patient remains alive without the benefit of drugs. HIV has been held at bay by the patient's immune system. The patient is what we refer to as a long-term non-progressor. These individuals exhibit no overt signs of immune destruction by HIV despite years of infection.
The terminology defining long-term non-progressors can get confusing as they are divided into one of two types:
- Elite controllers: no measurable virus detected using routine test
- Viremic controllers: viral loads < 2000 copies/mL
The patient I saw today is an elite controller, with no measurable virus in the blood.
Studying the mysteries of how elite controllers control HIV replication is thought to be key to developing a cure (see great graphic from amFAR) for HIV. Most current hypothesis are currently focused on what immune responses are operative in these patients (it is not thought that the HIV virus is defective in these patients nor the CD4 cells immune from infection).