martes, 1 de marzo de 2011

Transmitted HIV Resistance Ups Risk of Tx Failure

Estimados colegas, les dejo esto para su información.



 
Transmitted resistance to HIV drugs sharply increases the risk that a patient's first anti-retroviral regimen will fail, researchers reported.

In an analysis of more than 10,000 treatment-naive patients, transmitted resistance to at least one drug in the first regimen increased the risk of virological failure by a factor of three, compared with patients with no resistance mutations, according to Linda Wittkop, MD, of the University Bordeaux Segalen in Bordeaux, France, and colleagues.

On the other hand, patients who had transmitted resistance but were still placed on a fully active combination therapy were not significantly less likely to fail treatment, Wittkop and colleagues reported online in The Lancet.
Action Points  
  • Explain that in a multi-cohort study of over 10,000 patients, transmitted resistance to HIV drugs sharply increases the risk that a patient's first anti-retroviral regimen will fail.
  • Note that in contrast, patients who had transmitted resistance but were still placed on a fully active combination therapy were not significantly less likely to fail treatment.
  • Note that the vast majority of the patients, 90.5%, had no transmitted resistance on baseline testing.
The finding confirms recommendations that physicians and patients should choose an initial three-drug treatment regimen after resistance testing, Wittkop and colleagues argued.
Drug resistance is a continuing problem in HIV treatment, especially in the context of poor adherence, and if the resistant strains are transmitted, they are known to make treatment difficulty, the researchers noted.
But the effect of transmitted drug resistance has not been fully quantified in large numbers of patients, they reported.
To help fill the gap, they studied outcomes of 10,056 anti-retroviral-naïve patients who started combination therapy after Jan. 1, 1998, and had at least one sample for a genotypic test taken before the start of treatment.
The good news from the so-called EuroCoord-CHAIN study was that the vast majority of the patients -- 90.5% -- had no transmitted resistance, the researchers reported. Another 4.7% had at least one resistance mutation but still got fully active therapy.
And 4.8% had at least one mutation and were resistant to at least one of the drugs they were initially given, Wittkop and colleagues reported.
For the analysis, virological failure was defined as two consecutive viral loads over 500 copies for HIV RNA per milliliter of blood after six months of treatment, with the date of the first high viral load being the date of failure.
The researchers found that the cumulative Kaplan-Meier estimates for virological failure at 12 months were:
  • 4.2% for patients without resistance.
  • 4.7% for those with resistance but still fully active therapy.
  • And 15.1% for those with resistance to at least one of the drugs they were prescribed.
In a multivariate analysis, the hazard ratio for virologic failure was 1.47 when the patients who had resistance but active therapy were compared with the patients who had no treatment resistance. However the difference did not reach significance.
On the other hand, the hazard ratio for virologic failure was 3.13, with a 95% confidence interval from 2.33 to 4.20, when the patients with resistance to at least one drug in their first regimen were compared with those who had no resistance, the researchers reported. The difference was significant at P<0.0001.
While all the samples were taken before treatment started, not all were tested before a regimen was prescribed, the researchers noted, something that might have accounted for some of the sub-optimal regimens.

Primary source: The Lancet Infectious Diseases
Source reference:
Wittkop L, et al "Effect of transmitted drug resistance on virological and immunological response to initial combination antiretroviral therapy for HIV (EuroCoord-CHAIN joint project): A European multicohort study" Lancet Infect Dis 2011; DOI: 10.1016/S1473-3099(11)70032-9.
 

La mitad de la población masculina podría estar infectada por el virus del papiloma humano

 Estimados colegas, les dejo esta información sobre una ITS de importancia en relación al VIH.
Saludos
Dr. Carlos Erazo


"Un estudio publicado en “The Lancet” estima que cada año se infecta con el VPH16, causante de cáncer, el 6% de los varones.

Virus del papiloma humano.
Aproximadamente el 50% de los hombres de una muestra de la población general están infectados con el virus del papiloma humano (VPH), según un estudio del Instituto de Investigación y el Centro del Cáncer H. Lee Moffitt (Estados Unidos) que se publica en la edición digital de The Lancet.
 
Cada año, el 6% de los hombres adquirirá una nueva infección por el VPH16, el virus más conocido por causar el cáncer cervical en mujeres y también tumores en varones. Además, tener múltiples parejas, mujeres u hombres, se asocia en los varones a mayores probabilidades de adquirir la infección por el VPH.
 
Sólo en Estados Unidos se estima que 32.000 casos de cáncer en hombres y mujeres en 2009 eran atribuibles a la infección por VPH. Estos cánceres fueron de cuello de útero, vagina, vulva, pene, cavidad oral, cabeza y cuello y canal anal.
 
Las verrugas anogenitales son las consecuencias más comunes de la infección por el VPH. Además de las enfermedades que el VPH causa directamente en los hombres, el virus se transmite de forma directa de hombres a mujeres y afecta en gran medida al riesgo de enfermedad en mujeres. Por este motivo, el conocimiento de la naturaleza del VPH en hombres es crucial para la salud pública y puede utilizarse para determinar si la vacunación en hombres sería rentable.
 
El estudio analizó 1.159 hombres de entre 18 y 70 años de Estados Unidos, Brasil y México que no estaban infectados por el VPH y no tenían antecedentes de cáncer. Estas personas fueron evaluadas cada 6 meses durante una media de más de dos años. La incidencia de una nueva infección genital por VPH con cualquier tipo del virus fue de 38,4 por 1.000 personas al mes.
 
Las probabilidades de cáncer causado por la infección por el VPH fue 2,4 veces mayor en los hombres que tuvieron 50 o más parejas en comparación con no tener ninguna o solamente una; y 2,6 veces mayor en aquellos que tuvieron al menos tres compañeros sexuales anales masculinos en comparación con los que no tenían parejas recientes. La media de duración de la infección por el VIH fue de 7,5 meses en cualquiera de los tipos y 12 meses en el caso del VPH16 causante de cáncer.
 
Los autores concluyen que la incidencia de la infección del VPH genital en varones fue superior y relativamente constante en todos los grupos de edad en Brasil, México y Estados Unidos. “Los resultados del estudio proporcionan datos muy necesarios sobre la incidencia y eliminación de la infección en hombres por el VPH. Estos datos son esenciales para el desarrollo de modelos de rentabilidad realistas para la vacunación masculina por VPH a nivel internacional”, concluyen los autores."

National Black HIV/AIDS

Estimados colegas esta informacion en el CDC me parece importante .
Saludos
Dr. Carlos Erazo

 http://www.cdc.gov/mmwr/pdf/wk/mm6004.pdf

February 7 is National Black HIV/AIDS Awareness Day, an observance intended to raise awareness of the disproportionate impact of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) on the black population in the United States and to encourage prevention measures, such as HIV testing. Estimates of HIV incidence for 2006 indicated that blacks had a rate of 83.7 per 100,000 population, compared with 11.5 for whites (1). Two of the three goals of the National HIV/AIDS Strategy are to reduce new HIV infections and HIV disparities (2).

In 2006, male-to-male sexual contact was associated with an estimated 63% of new HIV infections among black males (3). Among black females, high-risk heterosexual contact was associated with an estimated 83% of new infections (3). Data from CDC’s National HIV Behavioral System show that, in 2008, 59% of HIV-infected black men who have sex with men (MSM) did not know they were infected, compared with 26% of white MSM (4).

Additional information regarding National Black HIV/AIDS Awareness Day is available at http://www.cdc.gov/features/blackhivaidsawareness. Additional information regarding blacks and HIV/AIDS is available at http://www.cdc.gov/hiv/topics/aa/index.htm.
References

Occupational HIV Transmission and Prevention among Health Care Workers

Estimado colega , les dejo este FACT SHEET del CDC sobre la prevención de la transmisión del VIH en trabajadores de la salud.
Saludos
Dr. Carlos Erazo
http://www.cdc.gov/hiv/resources/factsheets/PDF/hcw.pdf

Health care workers should assume that the blood and other body fluids from all patients are potentially infectious.
They should therefore follow infection control precautions at all times.
These precautions include:

• routinely using barriers (such as gloves and/ or goggles) when anticipating contact with blood or body fluids,
• immediately washing hands and other skin surfaces after contact with blood or body fluids, and
• carefully handling and disposing of sharp instruments during and after use.