During the first decade of the HIV epidemic, when the number of new cases of AIDS was growing exponentially, the consensus was that virtually every office-based physician with a broad clinical practice would eventually see some HIV-infected patients. The corollary conviction was that primary-care physicians should be willing -- and able -- to provide care to people with HIV disease. To make accurate diagnoses and provide adequate care, these practitioners would need a basic understanding of the pathogenesis of HIV infection, its presenting symptoms, and its clinical course. They would need to keep abreast of advances in antiretroviral therapy -- an ever-changing and increasingly dynamic field. And they would need to learn how to recognize, treat, and prevent the more common AIDS-related opportunistic infections.

With this objective in mind, the federal government set up regional centers to train physicians, and some states began to require a fixed number of hours of continuing medical education in the field of HIV treatment as a prerequisite for license renewal. The International AIDS Society - U.S.A., supported by educational grants from many of the same pharmaceutical companies that underwrite the publication of HIV Newsline and AIDS Care, undertook to offer a series of regional symposia on advances in the diagnosis and treatment of HIV disease. Other groups provided similar update sessions for office-based practitioners.

By the early 1990s there was near-universal agreement that AIDS had become a primary-care disease. Many primary-care physicians were seeing HIV-infected patients in their offices and clinics by the beginning of this decade, and most of those physicians were able to provide their patients with adequate continuing care by following treatment guidelines developed by the Centers for Disease Control, I.A.S. - U.S.A., and other organizations and agencies. Patients with particular problems were referred to specialists, but non-specialists assumed much of the day-to-day care of seropositive individuals.

This consensus was reached before the development of the HIV RNA assay to measure viral load, before the advent of the non-nucleoside reverse-transcriptase inhibitors and the protease inhibitors, and before the adoption of combination therapy as the standard of care for patients with advanced HIV disease. This pattern of clinical care was established before we fully understood the dynamics of viral replication -- particularly during what was once called the "latent" phase of HIV infection -- and before we fully appreciated the degree to which resistance and cross-resistance limit our therapeutic options.

All of these developments have had a significant impact on how we treat HIV infection. Indeed, they have led to the wholesale revision of treatment guidelines issued only a few years ago. We now recommend that treatment begin sooner, that it begin with a more potent regimen, and that it be changed promptly if it fails to suppress viral replication (see "Optimal Antiretroviral Therapy for HIV Infection," the Pull Out and Save section of the December 1997 issue of HIV Newsline).

"It is time to recognize that HIV infection is no longer a disease that practitioners with limited experience should attempt to treat. Over the past three or four years the treatment of HIV infection, particularly in its advanced stages, has become so complicated that it is now best left to those with the greatest expertise in treating the infection and its sequelae."

As importantly, all of these developments have made the continuing care of HIV-infected individuals significantly more complex -- so complex, in fact, that the optimal medical management of patients with HIV disease now requires a level of expertise that non-specialists cannot be expected to have. The time has therefore come to rescind the consensus we reached at the beginning of the decade. It is time to recognize that HIV infection is no longer a disease that practitioners with limited experience should attempt to treat. Over the past three or four years the treatment of HIV infection, particularly in its advanced stages, has become so complicated that it is now best left to those with the greatest expertise in treating the infection and its sequelae.

The continuing care of patients with HIV infection, no matter how dedicated and compassionate it may be, can cause real harm if that care does not rely upon the latest technological advances, does not correctly interpret the data provided by current HIV RNA assays, and does not take into account all that is now known about genotypic and phenotypic resistance to therapy. Well-intentioned but inadequately-informed decisions about when and how to initiate antiretroviral therapy -- or about when and how to change a failing multidrug regimen -- can leave a patient with reduced options and fewer chances of attaining and maintaining clinical stability.

As my colleague Dr. Steven Deeks made abundantly clear in an article entitled "Protease Inhibitor Resistance and Salvage Therapy," which appeared in the December 1997 issue of HIV Newsline (see Vol. 3, No. 6), patients who fail their initial combination antiretroviral regimens present a considerable clinical challenge, even to those of us who have been treating HIV-infected patients since the earliest days of the epidemic. We still know very little about the effectiveness of the various multidrug regimens that have been proposed -- and are being tried -- as salvage therapy in patients who break through on maximally suppressive antiretroviral therapy. And we also know very little about the potential side effects of these untested combinations.

For these reasons, Dr. Deeks declares, clinicians who treat such patients must rely "on their own experience and on the limited data that have come from the handful of small, often retrospective, studies that have been conducted to date." Clinicians who have extensive experience treating HIV infection -- and who are familiar with the data from those preliminary studies -- are in the best position to make these difficult decisions. They will know what options remain open to such patients, what combinations of compounds hold the most promise, and how a particular patient is likely to respond to a particular salvage regimen.

The technological and therapeutic advances of recent years have radically altered our approach to treating HIV infection, and they have dramatically altered the outlook for infected individuals. These new tools are two-edged swords, however. They enable us to measure viral activity more directly and more precisely than was once possible, and they permit us to individualize therapy to a degree that was heretofore impossible. But maximally suppressive therapy today is rather like atomic power was in its infancy: everyone sees its potential benefits, but not everyone recognizes its potential dangers.

These are extremely potent drugs, especially when they are taken in combination. During the first months of therapy they do bring viral replication to a virtual halt, but their use is often accompanied by "fallout," either from side effects -- which, while usually mild, may limit long-term tolerance -- or from poor adherence to therapy.

Taking these potent drugs incorrectly can lead to the rapid emergence of high-level resistance. Give a patient a suboptimal dose of any of the F.D.A.-approved protease inhibitors, for example, and you not only fail to suppress viral replication, you actually encourage the selection of drug-resistant viral strains. Give a patient any of these drugs as monotherapy, or add a single drug to a failing regimen, and the effect is the same. Indeed, in all instances the long-term result of prescribing the wrong dose or the wrong regimen is not simply to render a patient's viral isolates resistant to the chosen drug but to promote some degree of resistance to all drugs in that class.

"If it is hard, these days, for seasoned treaters of HIV disease with ready access to interim data from ongoing studies to keep up to date on advances in the clinical care of infected individuals, it is unreasonable to expect that office-based physicians with broad clinical practices that include only an occasional HIV-infected patient will be able to keep up. Wherever possible, seropositive patients, especially those with advanced disease, should be referred to more seasoned, better informed clinicians."

In the era of maximally suppressive antiretroviral therapy, then, choosing the right combination of drugs, choosing the right time to begin therapy, and choosing the right tools to monitor that therapy are all essential if patients are to enjoy the impressive benefits that can be obtained with maximally suppressive antiretroviral therapy. These choices can be made only by clinicians who understand the pathogenesis of HIV infection, its presenting symptoms, and its clinical course; who have kept abreast of advances in antiretroviral therapy; and who know how to recognize, treat, and prevent AIDS-related opportunistic infections.

If it is hard, these days, for seasoned treaters of HIV disease with ready access to interim data from ongoing studies to keep up to date on advances in the clinical care of infected individuals, it is unreasonable to expect that office-based physicians with broad clinical practices that include only an occasional HIV-infected patient will be able to keep up. Wherever possible, seropositive patients, especially those with advanced disease, should be referred to more seasoned, better informed clinicians. When referral is not possible, as is the case in under-served rural areas, providers will find the Internet a valuable source of current information on diagnosis and treatment (see "Working the Web," an easily followed road map to HIV/AIDS information on the Internet, in Vol. 2, No. 6 of HIV Newsline).

This is not to say that primary-care providers do not have a role to play in the diagnosis and treatment of HIV infection. Because they see all sorts of patients with all sorts of presenting symptoms, physicians who work in emergency rooms, walk-in clinics, community health centers, and similar facilities are the practitioners most likely to see cases of acute HIV infection and to pick up cases of undiagnosed infection. Moreover, these physicians, because they have established relationships with the communities they serve and rapport with the patients they see, are well suited to following asymptomatic HIV-positive patients who have not yet begun antiretroviral therapy -- assuming they monitor these individuals at appropriate intervals and refer them according to established guidelines. Nor should we slight the critical role these primary-care physicians play in prevention efforts.

"It is no longer possible for a single discipline to 'claim' HIV -- nor would anyone want that, given the complexity of the disease. Effective management of HIV disease, particularly in its advanced stages, requires a multidisciplinary approach, and even the experts rely on other experts to help them provide optimal care to AIDS patients. In a sense, the real test of who is -- and who isn't -- an expert on HIV infection is probably not a question of particular training but of passionate commitment."

If we agree that the best HIV care is provided by experts, how do we identify -- and certify -- those experts? Should they be trained in some special way? Should they be credentialled in some special way? Clearly some sort of national standard would be helpful, because what we have at the moment is an ad hoc approach that arose more or less spontaneously in various parts of the country in response to the first wave of reported cases and is being delivered by various types of physicians according to various sets of treatment guidelines. In some places, care is provided mostly by specialists in infectious disease, while in other places dermatologists, hematologists, pulmonologists, oncologists, and even family practitioners have become self-taught AIDS experts.

At this point many of those self-taught experts are first-rate specialists in the treatment of HIV disease, and it is no longer possible for a single discipline to "claim" HIV -- nor would anyone want that, given the complexity of HIV infection. Effective management of HIV disease, particularly in its advanced stages, requires a multidisciplinary approach, and even the experts rely on other experts to help them provide optimal care to AIDS patients. In a sense, then, the real test of who is -- and who isn't -- an expert on HIV infection is probably not a question of particular training but of passionate commitment. The experts are those who see the patients, attend the meetings, read the literature, review the data...and fine-tune their approach to clinical care accordingly.

An increasing number of young providers have actually chosen to specialize in the treatment of HIV disease. For the most part, however, it was the other way around: HIV chose us, through a combination of geographical circumstance and clinical happenstance. In my own case that specialization began in 1981, when I was completing my training in oncology at UCSF Medical School and San Francisco General Hospital. Our service saw some of the very first patients with what proved to be AIDS-related Kaposi's sarcoma lesions. These same patients went on to develop PCP, which few of us had ever seen, and MAC -- which none of us had ever seen. And as they did, my colleagues and I began the long and frustrating process of trying to figure out how to treat these rare infections. From time to time over the last 17 years I have found myself wondering when, if ever, I might be able to reëngage in the specialty I chose for myself and give up the one that chose me. The answer is always the same: Not yet.

"The Infectious Disease Society of America has appointed a committee to define the parameters of AIDS expertise and to invite the participation of HIV experts, whether they have formal training in infectious disease or not, to become members of an HIV-care sub-organization. In the end, this organization hopes to encourage the establishment of national criteria for the treatment of HIV infection."

Because HIV infection is going to be a fact of life for a long time to come, it is important that we develop ways of delivering the best possible care to infected individuals. One way in which the International AIDS Society - U.S.A. is assisting in that effort is by developing a voluntary registry of physicians across the country who provide care to people with HIV.

The Infectious Disease Society of America, for its part, has appointed a committee to define the parameters of AIDS expertise and to invite the participation of HIV experts, whether they have formal training in infectious disease or not, to become members of an HIV-care sub-organization. In the end, these organizations hope to encourage the establishment of national criteria for the treatment of HIV infection and the development of some process that can be used to determine whether a provider is really qualified to care for this complex disease. As importantly, these organizations' efforts will facilitate interaction among HIV experts, which will solidify our sense of community.

As these issues are being settled, how can we make sure that our patients with HIV are being well served? Requiring a certain number of hours of continuing medical education in the field of HIV treatment as a prerequisite for license renewal will clearly help in establishing a minimum standard of competence. Outcome data are also helpful in identifying providers who are particularly skilled at treating HIV disease -- and in detecting those whose skills are inadequate. But it has never been easy to monitor competence, especially in a field as dynamic as this one, and until a national organization determines a consensus standard of AIDS expertise there will be no good way to ensure that all patients have access to adequate care.

HIV Newsline and AIDS Care are our contributions to the effort to provide a single, high standard of care for all people with HIV. As I noted in the inaugural issue of HIV Newsline, "Our mission is a simple one: to provide clinicians with pertinent, practical, up-to-the-minute information on the diagnosis and long-term management of one of the most complex disease entities ever confronted by healthcare providers." The treatment of HIV infection has been revolutionized since January of 1995, when I wrote those words, but our mission remains the same.

Paul A. Volberding, M.D., is Editor-in-Chief of HIV Newsline and AIDS Program Director at San Francisco General Hospital.