THE ROLE OF THE ALLERGIST/IMMUNOLOGIST IN TREATING HIV INFECTION
HIV infection is an immune-mediated disease in a very direct manner since the HIV virus attacks, and kills the pivotal immune cell, the CD4+ T-helper cell. Thus, HIV infection is a secondary immunodeficiency that can be diagnosed and managed by the allergist/immunologist in consulting with other subspecialists, just as other types of secondary immunodeficiency (e.g., malnutrition, drug-induced immunosuppression) are handled. Allergist/immunologists should be capable of making a diagnosis of HIV infection in patients with recurrent infections and characteristic medical histories (e.g., HIV-at-risk exposures) and physical findings (e.g., lymphadenopathy, Kaposi sarcoma, wasting). Confirmation of the diagnosis in adults should be made by two antibody tests on separate blood specimens (ELISA and Western blot). In children under 18 months of age, because of confounding maternal antibody that crosses the placenta, two independent repetitive non-antibody tests are required; one obtained when the child is older than four months of age, (e.g., PCR test for HIV DNA). Once the diagnosis of HIV is established, it is very important to classify the state of HIV disease progression with the CDC classification system, e.g., A, B, or C (asymptomatic to very symptomatic) and stage of immunosuppression from 1 to 3 (normal to very suppressed), depending upon the CD4+ T-cell count.
In pediatrics, there is one more letter code (N) that stands for no symptoms, and the immunosuppression scale takes into account the relative lymphocytosis of infants and young children, (e.g., at less than a year of age, the numbers 1, 2, and 3 correspond to higher CD4+ T-cell counts).
The classification of patients is extremely important in knowing when to initiate antiretroviral therapy (nucleoside and non-nucleoside inhibitors of reverse transcriptors) and highly active antiretroviral therapy (mostly protease inhibitors). Since opinion on when to start treatment is changing, consultation with an infectious disease specialist is frequently helpful. Management of the immunological aspects of HIV infection should be part of the spectrum of clinical expertise of most newly trained allergists/immunologists.
The Texas Allergy, Asthma and Immunology Society (TAAIS) is a group of more than 220 board-certified Allergists/Immunologists in Texas. An Allergist/Immunologist is a physician, usually an Internist or Pediatrician, who has had special training and experience in the field of Allergy and Immunology and who is considered to be an expert in the diagnosis and management of immune system disorders such as asthma, allergic rhinitis (hayfever), eczema, urticaria (hives), drug reactions, food allergies, immune deficiencies, and all general aspects of anaphylaxis.
A Board Certified Allergist/Immunologist is a physician who has passed the certifying examination of the American Board of Allergy and Immunology. A list of Board Certified Allergists can be found at http://www.taais.org/membershipdirectory.html. Those with “ABAI” under Board Certification are Board Certified Allergists/Immunologists.