Ask Dr. Jeff
Question: I am HIV-positive and am currently not on any HIV meds. My work is offering free Hep A and B vaccines. Should I take these vaccines or could they make my HIV worse?
Answer: Vaccines for hepatitis A and B are not only safe, but should be offered to all HIV-positive people. While there is a short-term increase in HIV viral replication following vaccines, like these, or the flu shot, the benefits far outweigh the risks. The increase in viral load (HIV RNA) usually returns to baseline within 21 days. That is why you should always wait thirty days after any vaccination before obtaining an HIV RNA level. For sexually active gay men, hepatitis B is a real risk, and can be transmitted sexually much more readily than HIV. And, in the Seattle area, there have been several large outbreaks of hepatitis A in the last few years. Hepatitis A is transmitted by fecal-oral contamination associated with poor hygiene. An acute hepatitis A or B infection can have a serious effect on HIV infection, and hepatitis B may result in a chronic progressive infection. There have been a few deaths reported in people who have had hepatitis A infection on top of a preexisting hepatitis C infection (for which there is no vaccine). Many sexually active gay men have already been exposed to hepatitis B infection and may have developed a natural immunity, which can be assessed by measuring hepatitis B antibody levels (Seattle Gay Clinic, doctors offices and health departments can run these tests easily and cheaply). Also, the efficacy of these vaccines will be greater the earlier in the course of HIV infection, rather than later, when the immune system may be too weak to generate an effective antibody response.
One other consideration is whether or not you are considering beginning on anti-HIV therapy. If so, you might want to wait until after a few months of treatment for HIV, if your CD4 counts are low now (like below 200). A strengthened immune system will have a better chance of responding strongly to the vaccines.
Question: I have been on d4T, 3TC, and indinavir (Crixivan) and my viral load is below 50 copies/ml. I am starting to have problems with pains in my legs, which my doctor thinks is caused by the d4T. She feels that since my viral load is below detection that I can switch out only one drug without having to switch out the other two. What do you think?
Answer: The general rule has been that when someone is failing a combination of drugs, it is best to change all of the drugs to minimize the chance of resistance. But, this only applies to failure due to virologic failure (i.e. increasing viral load) due to drug resistance. When one drug is creating a problem, such as peripheral neuropathy, or pain in the legs, which all the "d" drugs can cause (ddC, ddI and d4T), it is only necessary to change that drug. Drugs in the NRTI class which do not cause significant neuropathy problems include 3TC, zidovudien (AZT), and the newly approved drug, abacavir (Ziagen). Most people would probably switch from d4T to zidovudine in this situation, and you should maintain the same degree of virologic control as with you current regimen. Abacavir is a newer drug, without as much experience as zidovudine, and can cause a hypersensitivity reaction in 3-5% of people requiring discontinuation, for which there is a potential risk of severe reaction, or even death, if the drug is then re-administered. The mechanism by which d4T causes neuropathy is different than neuropathy caused by ddI, so that would be another option, but would not be my first choice.
Question: I'm worried about HIV and the brain. Do I need to be on drugs like nevirapine or AZT that have been shown to get into the brain? Am I risking infection in the brain if I'm currently not on them?
Answer: Fortunately, currently available antiretroviral regimens seem to control HIV replication in the brain very well. There are no studies that show that in large trials any one regimen is superior to another in preventing central nervous system symptoms. However, in people with preexisting central nervous involvement due to HIV, which is symptomatic, zidovudine (AZT) has been shown to result in clinical improvement. Zidovudine penetrates very well into the brain. There is a debate about which protease inhibitors are better for brain penetration, but clinically they all seem to work equally well. One presentation in Chicago looked at indinavir (IDV) levels in the cerebrospinal fluid (CSF, and found that "IDV penetrates into the CSF in HIV-infected patients and persists over the 8 hour dosage interval." Other studies have looked at HIV in the CSF to see if drug-resistant HIV might be developing there, when it is not resistant in the blood. These studies have found that the virus in the blood and the CSF have the same resistance patterns. So, with the exception of including zidovudine in a regimen for someone with symptomatic HIV disease in the brain, I think any combination of currently available antiretrovirals work equally well on controlling HIV replication in the brain, compared to the blood.
This article was provided by Seattle Treatment Education Project. It is a part of the publication STEP Perspective.