The AIDS Epidemic in San Francisco: The Response of Community Physicians, 1981-1984, Vol. I

AIDS as a Disease Spectrum

AIDS Related Complex

Hughes

Please comment on AIDS Related Complex [ARC] as a diagnostic category. Is it still used?

Campbell

That is still used as a diagnosis and there's still an ICD-9 code for ARC. ARC would really be anybody who does not have a

---

CDC definition of AIDS, which now includes everybody who is 200 or less CD4 cells. So if you have, let's say, 225 CD4 cells and a specific symptom related to HIV, such as fatigue or diarrhea, you have ARC. ARC may be grounds for disability, but not automatically.

Hughes

So it is a useful category.

Campbell

Yes. It doesn't have a very clear-cut definition; it's that grey zone that's not AIDS but is symptomatic HIV infection. There was a 1982 CDC definition of AIDS, then there was a 1987 definition, and then there was a 1992 definition. Prior to the 1992 definition, ARC was very important, because there were many more people who had ARC, because they had never had an opportunistic infection and you couldn't say that they specifically had the wasting syndrome, which had fairly strict criteria for diagnosis. I think the term "wasting syndrome" was invented in 1987; this put many of the ARC people into the AIDS category.

Current Diagnosis and Prediction of Disease Progression

Hughes

Do you put people with ARC in a slightly different category, or do they all have AIDS in your mind?

Campbell

Well, when I put down a diagnosis for HIV infection I'll put down viral load da da da, CD4 da da da, history this, this, this, this. Like I might say, "HIV infection, asymptomatic, low viral load, CD4 500." Such a person is far from AIDS. Or I would say, "HIV infection, viral load 1 million, CD4's twenty, history, Pneumocystis, M. [Mycobacterium] avium, CMV." That's somebody who's on the extreme other end of the HIV disease/AIDS spectrum. The disease is staged by the CD4 number, the viral load, and all the specific illnesses which a patient has had. A typical ARC patient may be described like this: "HIV infection, viral load high, let's say 100,000, CD4 count 300, history: hairy leukoplakia, recurrent diarrhea." However, this is not a classical AIDS-defining illness. So that's the way I do it.

Hughes

So in your mind, the disease is a spectrum.

Campbell

It's a spectrum. You think of it in the dimension of the viral load, the strength of the immune system, the specific infections the person has had, and maybe also their ability to function. Because you might get somebody who has a high viral

---

low and very few CD4 cells, who's had Pneumocystis but is still working full-time, and let's say Karnofsky score ninety, ninety-five. I don't always put the Karnofsky score down, but I think somebody who's making a strict definition of a particular person would include the Karnofsky, the viral load, the CD4's, and the specific AIDS-defining illnesses.

Hughes

So this is a very mutable system too, isn't it? Because of all these scientific parameters that you now are able to obtain, you can place people along a spectrum, but with the understanding that when you go back six months from now, they very well may be in a different place on that spectrum. So none of this is static?

Campbell

None of it is static, but I think that these days when we see people, it's really fairly cut and dried. We know who's apt to be getting ill fairly soon, and we know who's not. If somebody has, let's say, a stable 200 CD4 count and, let's say, a viral load of 5,000, which is relatively low, and they're tolerating a bunch of antiretroviral drugs, and they don't have anything else which is AIDS-defining, we know that we're just going to see that person every three months for a routine visit, and they're not going to be getting sick in the near future.

But if you see somebody whose viral load has gone from, let's say, 10,000 to 500,000, and they're having little fevers, and they've had thrush for the first time, you know that something is going to happen soon, or they've become intolerant or resistant to a particular antiretroviral drug.

Hughes

That really is pretty predictable? People really do tend to progress in that fashion?

Campbell

Yes, and I think you get a lot of predictability through the viral load. If you take into consideration the viral load and the CD4's, plus just the way the person feels, you can get tremendous predictability as to who is going to be around a year or two or longer.

Hughes

This predictability became possible with the ability to detect accurately the viral load?

Campbell

I think there was predictability on the basis of the CD4 cells long ago, and predictability on the basis of what specific opportunistic infections somebody might have had. But then in August 1994, right after the Tokyo meeting [of the International Conference on AIDS], we started doing these viral loads. That added a much sharper dimension to somebody's profile, as to whether they were going to do well or not. Some

---

people run very low CD4 numbers but have very low viral loads; those people just tend to do much better than persons with low CD4 counts and higher viral loads.

Hughes

What you're describing is a syndrome that is being defined increasingly more exactly because of technological advances. Right?

Campbell

Yes.

Hepatitis and Evolving Disease Concepts

Hughes

Have you experienced anything else like this in your career, where you had a general definition of a disease, but as the years went on, it became much more scientifically specific?

Campbell

Yes, I am thinking of hepatitis C, which is a disease that's probably been around a little bit longer than AIDS, but maybe not, and that we were calling non-A, non-B hepatitis, or transfusion hepatitis. Only in the last year or two, people have been doing studies about the natural history of hepatitis C. Now people are doing work on the gene types of hepatitis C. There are certain gene types of hepatitis C that are more amenable to interferon therapy than others. So that's a disease that's conforming very much to the same model as HIV.

Hughes

Are you saying that now we have the technology to define it more precisely?

##

Campbell

Hepatitis B became definable around 1971, and screening of the blood supply for hepatitis B was introduced in the early seventies. Many cases of transfusion hepatitis were eliminated, but not all of them, because some of them were non-A, non-B. A few years later, in 1976, we could define hepatitis A, so eventually in the late seventies, we had non-A, non-B. And now they have E and F, so there's non-A, non-B, non-C, non-E, non-F. So the waste basket is getting smaller and smaller, but never ends. I don't know if anybody knows how long hepatitis C has been around. We don't know if the people who died of a viral hepatitis or cirrhosis twenty years ago had hepatitis B or hepatitis C or what they had.

---

Hughes

The bloods that were stored for the hepatitis B vaccine trials in the early eighties don't provide information about hepatitis C?

Campbell

It could be. I really never thought much about it from a researcher's point of view. I think in many, many diseases, AIDS included, the natural history changes from decade to decade because the treatment changes.

Hughes

Yes, and in the case of the AIDS epidemic, also the populations being affected. I'm thinking of the disease in Africa, for example, which manifests itself differently in many ways than it does here.

Campbell

Yes, because the interventions are not quite the same. Coronary artery disease is another one in which there are so many new interventions such that people with that particular disease have specifically different problems than they did twenty years ago. Or diabetes.

Hughes

So this evolution of disease concept is nothing new to medicine.

Campbell

No, and there are always new infectious agents, like the hantavirus and [the micro-organism of] Legionnaire's disease. New infectious diseases that may have been seen sporadically before may emerge in epidemics now.

About this text
Courtesy of Regional Oral History Office, University of California, Berkeley
http://content.cdlib.org/view?docId=kt6580067h&brand=oac4
Title: The AIDS Epidemic in San Francisco: The Response of Community Physicians, 1981-1984, Vol. I
By:  Sally Smith Hughes
Date: 1996
Contributing Institution: Regional Oral History Office, University of California, Berkeley
Copyright Note: Copyright status unknown. Some materials in these collections may be - protected by the U.S. Copyright Law (Title 17, U.S.C.). In addition, the - reproduction, and/or commercial use, of some materials may be restricted - by gift or purchase agreements, donor restrictions, privacy and - publicity rights, licensing agreements, and/or trademark rights. - Distribution or reproduction of materials protected by copyright beyond - that allowed by fair use requires the written permission of the - copyright owners. To the extent that restrictions other than copyright - apply, permission for distribution or reproduction from the applicable - rights holder is also required. Responsibility for obtaining - permissions, and for any use rests exclusively with the user.