Post-exposure prophylaxis for HIV: Difference between revisions

Latest revision as of 18:50, 5 July 2022

Background

Can be sexual or non-sexual; consensual or non-consensual; and heterosexual or homosexual
HIV does not survive very long outside of the human body, which is why a random needle in park, for example, is very low risk

Management

Risk Assessment

If the source person is available and consents to testing, this can be done to more accurately risk stratify the exposure
In general, prophylaxis is indicated if the estimated risk is greater than 0.1%

Risk of HIV-positive source
Risk	Examples
substantial	HIV-positive with detectable viral load (100%)
substantial	HIV status unknown, but from a population with high prevalence such as MSM (~23%) or PWID (~13%)
low but nonzero	HIV positive and believed to have undetectable viral load, with concomitant STI at time of exposure
negligible or none	confirmed HIV negative (0%)
	HIV positive with confirmed viral load <40 copies/mL without known STI at time of exposure
	HIV status unknown, in the general population (0.25%)

Risk of HIV transmission per act by exposure type from an HIV-positive source
Risk	Exposure	Estimated risk per act %
Very high	Transfusion	92.5
High	Anal (receptive)	1.38
High	Needle sharing	0.63
Moderate	Anal (insertive)	0.11
	Vaginal (receptive)	0.08
	Vaginal (insertive)	0.04
Low	Oral sex (giving)	—
	Oral sex (receiving)	—
	Oral-anal contact	—
	Sharing sex toys	—
	Blood on compromised skin	—
Negligible	Found needle	—

Recommended management by source and exposure risk
Risk of HIV-Positive Source	Risk From Exposure	Action
substantial	low	PEP not required
substantial	moderate or high	initiate PEP
low	low	PEP not required
low	moderate or high	consider PEP
negligible or none	low	PEP not required
negligible or none	moderate or high	PEP not required

Antiretroviral Therapy

Screen for sexual assault, counsel about safe sex
Screen for pregnancy and get baseline investigations (below)
Start antiretroviral therapy within 72 hours and continue for 28 days
- First-line: tenofovir disoproxil fumarate/emtricitabine 300 mg/200 mg PO daily plus raltegravir 400 PO bid
- Alternative: tenofovir disoproxil fumarate/emtricitabine 300 mg/200 mg PO daily plus dolutegravir 50 mg PO daily
- Alternative: tenofovir disoproxil fumarate/emtricitabine 300 mg/200 mg PO daily plus darunavir/ritonavir 800 mg/100 mg PO daily
Don't forget screening for hepatitis A, hepatitis B, hepatitis C, gonorrhea, chlamydia, and syphilis

Investigations

Investigation	Baseline	Week 12	Notes
CBC	X
ALT	X		repeat at 2 weeks if abnormal
creatinine	X		repeat at 2 weeks if abnormal
hepatitis A serology	X
hepatitis B serology	X		includes HBsAb, HBsAg, and HBcAb
pregnancy test	X
HIV serology	X	X	repeat at 6 months if hepatitis C seroconversion
hepatitis C serology	X	X
gonorrhea and chlamydia	X	X	urine, throat, and rectum, depending on reported sexual activity
syphilis serology	X	X

Follow-Up

Initial visit; follow-up at 4-6 weeks; then repeat bloodwork at 12 weeks to 4 months
Take advantage of the opportunity to counsel patients on STIs, substance use, etc.

@@ Line 1: / Line 1: @@
-==Exposures==
+==Background==
 *Can be sexual or non-sexual; consensual or non-consensual; and heterosexual or homosexual
+*HIV does not survive very long outside of the human body, which is why a random needle in park, for example, is very low risk
-==Risk Assessment==
+==Management==
+===Risk Assessment===
+*If the source person is available and consents to testing, this can be done to more accurately risk stratify the exposure
+*In general, prophylaxis is indicated if the estimated risk is '''greater than 0.1%'''
+{| class="wikitable"
+|+Risk of HIV-positive source
+!Risk
+!Examples
+|-
+| rowspan="2" |substantial
+|HIV-positive with detectable viral load (100%)
+|-
+|HIV status unknown, but from a population with high prevalence such as MSM (~23%) or PWID (~13%)
+|-
+|low but nonzero
+|HIV positive and believed to have undetectable viral load, with concomitant STI at time of exposure
+|-
+| rowspan="3" |negligible or none
+|confirmed HIV negative (0%)
+|-
+|HIV positive with confirmed viral load <40 copies/mL without known STI at time of exposure
+|-
+|HIV status unknown, in the general population (0.25%)
+|}
 {| class="wikitable"
+|+Risk of HIV transmission per act by exposure type from an HIV-positive source
-!Level
+!Risk
 !Exposure
 ! align="center" |Estimated risk per act %
@@ Line 45: / Line 73: @@
 |-
 |Blood on compromised skin
+| align="center" |—
+|-
+|Negligible
+|Found needle
 | align="center" |—
 |}
+{| class="wikitable"
-==Investigations==
+|+Recommended management by source and exposure risk
+!Risk of HIV-Positive Source
+!Risk From Exposure
+!Action
+|-
+| rowspan="2" |substantial
+|low
+|PEP not required
+|-
+|moderate or high
+|initiate PEP
+|-
+| rowspan="2" |low
+|low
+|PEP not required
+|-
+|moderate or high
+|consider PEP
+|-
+| rowspan="2" |negligible or none
+|low
+|PEP not required
+|-
+|moderate or high
+|PEP not required
+|}
+===Antiretroviral Therapy===
-*HIV testing at baseline and 12 weeks
-*HAV-Ab, HBsAg/sAb/cAb at baseline
-*HCV-Ab at baseline and 12 weeks
-*Gonorrhea and chlamydia of urine, throat, and rectum at baseline and 12 weeks
-*Sypthilis at baseline and 12 weeks
-*CBC at baseline
-*ALT and creatinine at baseline, repeated at 2 weeks if abnormal
-*Pregnancy test at baseline
-==Treatment==
 *Screen for sexual assault, counsel about safe sex
+*Screen for pregnancy and get baseline investigations (below)
-*Start treatment within 72 hours
+*Start antiretroviral therapy within '''72 hours''' and continue for 28 days
-*Tenofovir/emtricitabine 300/200 with raltegravir 400 BID, for 28 days
+**First-line: [[tenofovir disoproxil fumarate]]/[[emtricitabine]] 300 mg/200 mg PO daily plus [[raltegravir]] 400 PO bid
-**Preferred alternatives include TDF/FTC with darunavir/ritonavir or dolutegravir
+**Alternative: [[tenofovir disoproxil fumarate]]/[[emtricitabine]] 300 mg/200 mg PO daily plus [[dolutegravir]] 50 mg PO daily
-**Other alternatives include many
+**Alternative: [[tenofovir disoproxil fumarate]]/[[emtricitabine]] 300 mg/200 mg PO daily plus [[darunavir]]/[[ritonavir]] 800 mg/100 mg PO daily
-*Don't forget above screening
+*Don't forget screening for [[Hepatitis A virus|hepatitis A]], [[Hepatitis B virus|hepatitis B]], [[Hepatitis C virus|hepatitis C]], [[gonorrhea]], [[chlamydia]], and [[syphilis]]
+===Investigations===
+{| class="wikitable"
+!Investigation
+!Baseline
+!Week 12
+!Notes
+|-
+|CBC
+| style="text-align:center;" |X
+|
+|
+|-
+|ALT
+| style="text-align:center;" |X
+|
+|repeat at 2 weeks if abnormal
+|-
+|creatinine
+| style="text-align:center;" |X
+|
+|repeat at 2 weeks if abnormal
+|-
+|[[Hepatitis A virus|hepatitis A]] serology
+| style="text-align:center;" |X
+|
+|
+|-
+|[[Hepatitis B virus|hepatitis B]] serology
+| style="text-align:center;" |X
+|
+|includes HBsAb, HBsAg, and HBcAb
+|-
+|pregnancy test
+| style="text-align:center;" |X
+|
+|
+|-
+|[[HIV|HIV]] serology
+| style="text-align:center;" |X
+| style="text-align:center;" |X
+|repeat at 6 months if hepatitis C seroconversion
+|-
+|[[hepatitis C]] serology
+| style="text-align:center;" |X
+| style="text-align:center;" |X
+|
+|-
+|[[gonorrhea]] and [[chlamydia]]
+| style="text-align:center;" |X
+| style="text-align:center;" |X
+|urine, throat, and rectum, depending on reported sexual activity
+|-
+|[[syphilis]] serology
+| style="text-align:center;" |X
+| style="text-align:center;" |X
+|
+|}
-==Follow-up==
+===Follow-Up===
-*Initial visit; follow-up at 4-6 weeks; then repeat bloodwork at 4 months
+*Initial visit; follow-up at 4-6 weeks; then repeat bloodwork at 12 weeks to 4 months
 *Take advantage of the opportunity to counsel patients on STIs, substance use, etc.
 ==Further Reading==
-*Tan ''et al''. [https://doi.org/10.1503/cmaj.170494 Canadian guideline on HIV pre-exposure prophylaxis and nonoccupational postexposure prophylaxis]. ''CMAJ'' 2017;189(47):e1448-e1458.
+*Canadian guideline on HIV pre-exposure prophylaxis and nonoccupational postexposure prophylaxis. ''CMAJ''. 2017;189(47):e1448-e1458. doi: [https://doi.org/10.1503/cmaj.170494 10.1503/cmaj.170494]
 [[Category:HIV]]