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Infectious Diseases
Basic Science Correlate
Raltegravir, elvitegravir, and dolutegravir are integrase inhibitors. This agent
prevents the integration of the genetic material of the HIV virus from being
integrated into the CD4 cell chromosome. HIV is an RNA virus. Reverse
transcriptase turns it into DNA, and this viral DNA must be integrated into
human DNA in order to be reproduced. This is the step blocked by the
integrase inhibitor raltegravir.
Basic Science Correlate
Chemokine receptor 5 (CCR5) is the mechanism whereby the HIV virus
enters the CD4 cell. CCR5 is the attachment point of the GP120 on the
surface of the HIV virus whereby it finds its way into human cells. Maraviroc
is an entry inhibitor: Maraviroc blocks the CCR5 receptor.
Needle-Stick Injury (Postexposure Prophylaxis)
With any significant exposure to HIV-positive blood via a needle, scalpel, or
penetrating injury, the answer is the same: HAART for a month.
This would also be true for the exposure of mucosal surfaces to HIV-positive
blood or after unprotected sexual contact with a person known to be HIVpositive.
Basic Science Correlate
Ritonavir inhibits hepatic p450 systems—the route through which protease
inhibitors are metabolized. A small amount of ritonavir blocks metabolism
of the other protease inhibitors, allowing higher blood levels with less
frequent dosing.
Pregnancy/Perinatal
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If the patient is already on antiretroviral therapy for her own health, then
simply continue the same therapy.
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Mother-to-child transmission with fully suppressive anti-retroviral therapy
is < 1%. Every HIV-positive pregnant woman should be on HIV medications
regardless of the stage of her pregnancy or her CD4 count. Efavirenz is
avoided in pregnancy. Protease inhibitors with 2 nucleosides—such as zidovudine
and lamivudine—are best. Do not wait for the second trimester of
pregnancy to start therapy.
Start HIV+ pregnant
women on HIV medications
in the first trimester and
continue.
All HIV+ pregnant women
at any CD4 or viral load
need treatment.
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