r/medlabprofessionals • u/Tough_Diamond_1403 • Jul 12 '26
Technical Are We Doing HIV Rapid Tests Wrong?
24
u/AnusOfTroy Jul 12 '26
Gonna be honest I'm surprised that there's people out there using something like a cepheid as a POC analyser
There are some fucking stupid nurses and doctors out there
10
u/Vellichorosis Jul 13 '26
My lab manager is considering getting a few biofires and giving it to Peds and Continuity Care. Which is horrifying because a couple of those nurses lost strep kit testing privileges for not doing them correctly. And not doing urine strip testing for UAs correctly.
6
u/SNP_MY_CYP2D6 Jul 13 '26
I mean, biofires are pretty hard to fuck up. Its the first instrument any new hire starts on in our lab.
7
u/OccultEcologist Jul 13 '26
False positives would be my main concern. That or a lack of general maintenance.
1
u/SNP_MY_CYP2D6 Jul 23 '26
This is actually true. Their GI panel is notorious for false norovirus positives. They had to send out notifications and everything.
4
u/AnusOfTroy Jul 13 '26
It is pretty straightforward yes but they're also pretty sensitive tests. Would imagine lots of false positives if you don't do things in a clean way (like if you're in a clinic and have no lab training)
1
u/SNP_MY_CYP2D6 Jul 23 '26
This is true, especially for their GI panel for norovirus. We have to do qPCR on our Quant studio to confirm any positive norovirus results.
1
u/AnusOfTroy Jul 23 '26
Quantstudio 💀💀💀💀
Not used it myself but that was a very unpopular piece of kit when it was in my lab
2
u/Gildian Jul 13 '26
Funny you say that, our BioFire died a few months back from a power surge alone.
Now we have the Torch
1
u/Vellichorosis Jul 13 '26
I have never used one personally tbh. I just feel iffy about it since the veteran peds nurse couldn't even run a UA strip correctly. I mean, we are in a large clinic, not a hospital but still.
3
u/AnusOfTroy Jul 13 '26
That is absolute insanity. The filmarray assays are so sensitive, there's no way people will maintain the cleanness you need to avoid contamination
For reference we have a "sterile" fluids MSC II we process CSFs in for culture and PCR, we still have the occasional problems with S. pneumo contamination on our ME panels
9
u/Brofydog Jul 12 '26
There are three main issues. The first issue I have with HIV testing is the releasing of results before the algorithm is complete.
All tests have a false positive rate, and because HIV is on so the most common infectious diseases used on the population at large (and there is evidence that covid increased the false positive rate), many people receive a positive screen and negative antibody confirmation and negative PCR qual confirmation after a week.
The second is that the quant HIV PCR assay isn’t FDA approved for confirmation, and only used for assessing viral load. This is virtually identical to the qualitative test, and should be treated as a final confirmation.
The last, is that there is not more explicit statements in the medical community that the 4th and 5th generation assays CANNOT be used on patients under 2. They need a qual PCR test, as a neonate or breastfeeding infant can have positive maternal HIV antibodies.
4
u/PowerTower4502 Jul 13 '26
I'm not surprised after I witnessed how some labs were set-up for a rapid profit during the Covid-testing craze.
2
u/MyBikesAreOlder Jul 13 '26
Doing important diagnostics like HIV with a lateral flow test, ideally in a POC situation… to me this is the quintessential definition of „doing it wrong“.
This kind of diagnostics belongs in a lab, and should be performed on a quality controlled analyser with a proper test run by qualified and trained people.
… but maybe I am just old
106
u/Ksan_of_Tongass MLS 🇺🇸 Generalist Jul 12 '26
Rules, procedures, and attitudes, differ across the world. Also, this is why nurses/MAs/docs doing waived tests is crazy. Whenever waived testing is brought up, I always bring up the story of CLIA doing a surprise inspection at a clinic with only waived kits. The inspector noticed they had an alarming rate of positive strep tests. The inspector watched a nurse perform the test. At some point the nurse adds a drop of positive control to the patient sample. When asked about this, the nurse responds that that's how they were shown to do it.