A Case of Long-Term Seronegative Human Immunodeficiency Virus (HIV) Infection: The Importance of the Humoral Response to HIV

Seronegative HIV-1 infection in a Japanese man presenting with Pneumocystis pneumonia: Analysis of long-term antibody response and literature review

Seronegative human immunodeficiency virus (HIV) infection, where an HIV-specific antibody response is lacking even in chronic or late-stage HIV infections, is extremely rare. Here, we report the case of a 50-year-old Japanese man presenting with Pneumocystis pneumonia who did not produce antibodies against HIV-1 until the initiation of antiretroviral therapy (ART). Fourth-generation antigen-antibody testing temporarily reverted from weakly positive to negative soon after initiating ART, likely due to a reduction in viral load (assessed by p24 antigen levels). His HIV-1 antibody titers remained low or indeterminate even after four years of ART. A literature review suggested that the absence of HIV-1-specific antibody production may be associated with unimpeded HIV replication and rapid CD4+ T cell decline. Seronegative HIV infection can lead to deferred diagnosis and treatment, thereby increasing the risk of transmitting the virus to others or developing opportunistic illnesses. It is important to combine multiple tests for diagnosis, depending on the medical condition. Further studies are required to investigate the host factors involved in the production of HIV-1-specific antibodies.

Cryptococcal meningitis: an unusual presentation of primary HIV infection

Acute HIV infection presenting as severe opportunistic disease is a very uncommon event associated with more rapid HIV progression and higher mortality. We describe the case of a patient with cryptococcal meningitis in the setting of primary HIV infection.

Combating the HIV reservoirs

Impressive advances have been made in the treatment and management of HIV-1 infected individuals. Combination antiretroviral therapy (cART) has turned HIV-1 infection from an almost invariable deadly infectious disease, to a lifelong manageable infectious disease. However, a cure or vaccine has not been forthcoming. A major problem in HIV-1 infection is the persistent and latently infected cellular and tissue reservoirs. One of these reservoirs is the Gut Associated Lymphoid tissue (GALT), which has been the research focus of our group. Our group and others have shown that HIV-1 evolves differently in different parts of the gastro intestinal tract, which also appears to affect the development of antiretroviral drug resistance. The GALT is not the only reservoir. HIV-1 continues to persist and evolve in various other cell and tissue reservoirs despite intense and apparent successful antiretroviral therapy. Moreover, drug resistance mutations remain prevalent under therapy and successful viral suppression. In addition to finding a vaccine, the research on combating and eradicating the HIV-1 viral reservoirs has also been an important focus of HIV-1 cure strategies. We will discuss some of the research findings on reservoirs in the context of some of the HIV-1 cure approaches.

Uses for an HIV specimen repository: experience and lessons for other conditions

Biobanking is increasingly becoming recognized as an emerging resource for enhancing both clinical care and research. Establishing a useful repository of clinical specimens is, however, challenging. Below we discuss the barriers encountered and lessons learned while developing and using a specimen repository integrated into an HIV care program. Substantial effort, time, cost and foresight coupled with good fortune in establishing a biobank are, however, needed to improve patient care and research productivity. Disease and population selection, ethics, legal implications, costs and sustainable funding are critical areas to consider prior to initiating a repository. We discuss these topics and demonstrate some of the beneficial results achieved in HIV, which may be relevant to other conditions, from establishing even a small repository.