HIV and ID Observations

February 15th, 2021

Time to Fix the HIV Testing Algorithm — and Here’s How to Do It

Remember the revised HIV testing algorithm that debuted in 2014? The one that was supposed to solve all our problems? First, it included a “highly sensitive” screening test that started with a “4th Generation” combination antibody/antigen test. This decreased the window period between acquiring HIV and having a positive test, thanks to the antigen. Great! (These “generation” […]

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October 7th, 2019

Our HIV Testing Algorithm Has a Major Problem — Here’s How to Fix It

Mostly, HIV testing works great. It’s long been so accurate that we can strongly support HIV testing even in relatively low-risk people. The 2014 revised lab testing guidelines made it even better, recommending a combined antigen/antibody screening test (called the 4th generation test), and replacing the Western blot with the HIV-1/2 differentiation immunoassay as the preferred […]

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September 18th, 2016

Ten Years After Landmark HIV Testing Guidelines, How Are We Doing? Specifically in Emergency Departments?

In the late 1990s, a patient was admitted to our hospital with HIV-associated PCP. He had advanced AIDS, a CD4 cell count < 100, and was sick enough to require a temporary stay in our ICU. Those clinical details aren’t so remarkable — “late” diagnoses of HIV still happen, and happened even more back then. What’s […]

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September 4th, 2016

The Most Common Question About the New HIV Testing Algorithm, Answered

A primary care doctor in the Boston area recently emailed me this question: Hi Paul, A 28yo woman had a positive 4th gen +Ag/Ab assay, but a negative HIV-1/2 differentiation assay and negative HIV viral load. She had no signs of acute HIV, but is not using condoms with her partner, whose HIV status she doesn’t know. We repeated the test […]

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July 7th, 2015

For HIV in the USA, Not in Care Exceeds the Undiagnosed — Solutions Welcome

In last week’s post, I asked about two of the key components of the HIV care cascade — the “undiagnosed” vs the “diagnosed but not in care,” and which group was larger in the USA. Here are your answers as of now: The people who read this site are a pretty knowledgeable group when it comes to […]

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October 7th, 2013

CD4 Cell Count at Presentation: A Figure with a Depressingly Small Upward Slope

You know how to make an ID/HIV specialist angry? Frustrated? Sigh loudly? Tell a clinical anecdote that involves “late” presentation of HIV diagnosis, in particular someone who has been seeking medical care for various ailments for months or even years without getting tested. You know — it goes something like this: “He was seen 3 years ago for […]

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June 20th, 2013

Let’s Move the HIV Testing Algorithm Into the 21st Century

As I’ve written before, the most widely used testing algorithm for HIV — enzyme immunoassay followed, if positive, by Western blot confirmation — is long overdue for an update. A brief review why this is the case, and also why sticking with it is so problematic: Immunoassays have become progressively more sensitive, especially when paired with p24 […]

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November 22nd, 2012

The U.S. Preventive Services Task Force Recommends HIV Screening — And Why is This News?

A flurry of coverage recently appeared about the U.S. Preventive Services Task Force’s recommendation for one-time HIV screening for all Americans, ages 15-64. Some might wonder why this is news — um, hasn’t this been recommended now for years? — and I think I’ve figured it out. Let me start by relaying that every ID/HIV specialists can tell […]

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September 19th, 2012

It’s Time to Dump the HIV Western Blot

Hard to believe, but we have to get rid of the HIV Western blot — at least as our HIV confirmatory test. Here’s why (case adapted from several seen the past few years; I’m sure most of you have seen similar): 30-year-old man, high risk for HIV. He’s worried he might have become infected due to recent […]

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July 26th, 2012

Pigs are Flying: Written Consent No Longer Needed for an HIV Test in Massachusetts

Let the record show that as of July 26, 2012, a person in Massachusetts can legally get an HIV test without signing a written consent. Hooray. There, that wasn’t so hard, was it?

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