PI Perspective #47

December 2008     View PDF     En español

News briefs from ICAAC / IDSA

by Alan McCord

New blood test may facilitate better TB diagnoses
Diagnosing TB (Mycobacterium tuberculosis) infection, active and latent disease, and treatment success can be difficult. In fact, accurately finding active TB disease in people with HIV is complicated by poor results from commonly used tests in this population, such as the tuberculin skin test (TST) and acid fast bacillus (AFB) smear. A poster presented early data on a small study examining a new blood test called TSPOT to more accurately diagnose active TB in HIV-positive people. The results showed generally positive data on the test’s ability to find TB in 8 of 10 of the people with active TB. It generally outperformed TSTs and AFBs. Though more research is needed to more fully qualify its effectiveness, it may lead to being a better diagnostic tool for testing and treating TB in HIV-positive people.  Read full article.

Risk factors for anal cancer include low CD4 count
A poster presented data from a small retrospective study on the risk factors for anal cancer in HIV-positive men. Infection with the human papillomavirus (HPV) is a growing health concern for people living with HIV, especially men who have sex with men. For each case that was diagnosed (15 total), three HIV-positive men without anal cancer were randomly chosen as a control group. CD4s for the group with anal cancer averaged 224 while the other group averaged 409. As with most co-infections in HIV disease, HIV-infected men appear to be more at risk for anal cancer as their CD4s decrease towards 200 and below. Also, higher viral loads and longer time living with HIV were not shown to be risks for anal cancer. These results add to the growing body of information regarding HPV disease in people with HIV. Though no great leaps have been illuminated with these results, they continue to point to heightened screening and diagnosis of HPV disease in all people living with HIV.  Read full article.

Syphilis does not increase risk of AIDS or death
A poster presented information on the effect of syphilis on an HIV-positive individual’s risk to AIDS and/or death. This common sexually transmitted infection can decrease CD4 counts in people with HIV. Syphilis can also increase HIV levels, which can stay elevated even after its successful treatment. Results from a prospective, observational study was conducted using a US military cohort of 2,239 people. The study analyzed time to AIDS or death or time to death alone. It adjusted for CD4 count, age, race, gender and hepatitis B/C status. The results showed that having a confirmed or probable case of syphilis was not a risk factor for progressing faster to an AIDS diagnosis or death.  Read full article.

Adding GM-CSF to hepatitis B vaccine fails to work
People living with HIV are at risk for getting the hepatitis B virus (HBV). They also have a higher risk of HBV disease and death. Although current HBV vaccines protect about 90% of the time, they don’t offer the same level of protection for HIV-positive people. To be most effective, the vaccine should be given at higher CD4 counts. Yet even this does not ensure immunity and not all people with HIV have high CD4 counts at the time of vaccination. A poster presented phase II data on an HBV vaccine given with GM-CSF (granulocyte-macrophage colony-stimulating factor), a protein produced by many immune cells. This was done in the hopes for a more durable protective effect from the vaccine. Unfortunately, the results showed that using GM-CSF did not produce any added protection over the group given the placebo. Studies like this one, even with disappointing results, are critical to finding ways to further protect people living with HIV at risk for HBV infection.  Read full article.

Meningococcal vaccine appears safe in youth with HIV
A poster showed positive results from a study of the meningococcal vaccine (MCV4, Menactra) in youth living with HIV. The vaccine prevents infection with the N. meningitidis bacteria that causes several meningococcal diseases such as meningitis. The safety of the vaccine has not been studied in HIV-positive adolescents. This phase I/II study followed 3 groups of 319 youth aged 11 to 24 years. All three groups took one dose of the vaccine at study start. At 24 weeks, group 1 received a second dose while groups 2 and 3 were randomized to take or not take a second dose. The results showed that the vaccine was safe to use as two doses in HIV-positive youth aged 11 to 25 years of age. This was true across the spectrum of CD4 percentages studied.  Read full article.

Study suggests a more virulent HIV today
A poster presented interesting information on HIV’s possibly maturing “virulence”. This ongoing Tri-Service AIDS Clinical Consortium study highlights a gradually lowering trend in baseline CD4 counts in newly diagnosed people in today’s epidemic compared to 1985. The retrospective study looked at 1,944 newly diagnosed people at 7 US military medical centers. Each had their first CD4 count done within 6 months of diagnosis, and no one took HIV therapy before their baseline CD4. A lowering trend in average CD4 counts were noted over a series of four periods of 6, 5, 6 and 3 years at 632, 555, 495 and 499 CD4s. Although the study suggests these lower CD4 counts may be due to a more “virulent” HIV today, a 2004 Swiss study contradicts this with a result that HIV is not more virulent today. Also, very few in the study were women, much less than what is seen in the US epidemic. As well, this was a military cohort and no information was provided on factors such as rates of deployment or co-morbidities — each of which could skew the results.  Read full article.

Four weeks of therapy enough to
prevent mother-to-child transmissions
A poster of an Irish study shows the US guidelines for HIV-exposed infants getting 6 weeks of HIV therapy to prevent mother-to-child transmission (MTCT) can be shortened to 4. The study mentions the US Guidelines’ lack of definitive evidence supporting its recommendation. This retrospective audit of the Irish Prevent MTCT program examined the pregnancies of 868 women from 01/99 to 12/07. One of two regimens were given to the infants: Retrovir or Retrovir + Viramune + Epivir. The results showed that the MTCT rate equaled 1%, which is lower than global standards of an acceptable MTCT rate. These results likely won’t be enough to encourage the US to change its Guidelines, but they may persuade prospective study of this issue.  Read full article.

ADAPs and maximizing health outcomes for all eligibles
The federal AIDS Drug Assistance Program (ADAP) is set up in each state to ensure that those living with HIV who cannot cover the cost of their HIV meds can still access them. Due to tightening state budgets, ADAPs are providing services to an ever-growing list of people in need, often limiting eligibility on a first-come, first-served basis. This has caused some who may more quickly progress in their HIV disease to not start HIV therapy soon enough. A poster presented data from a study that used a simulated model with characteristics from the Massachusetts ADAP and prioritized enrollees by CD4 count when the ADAP is faced with limited resources in the hopes of minimizing the rate of adverse health events while containing costs. The model revealed that basing eligibility on CD4 count rather than on a first-come, first-served basis resulted in lower rates of opportunistic infections and death while not negatively impacting others with better health who had to wait. This model only simulated an ADAP, and it’s unknown how this information would be used by US ADAPs. However, it does lay some interesting groundwork for looking at this issue of maximizing limited state resources.  Read full article.