Greetings! I have been here in the past with concerns over BIOTIN (Vitamin B7) potentially interfering with HIV 1-2 Ab/p24 Ag combo tests. If all of this commotion started because of this study (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7703309/), we need to break it down, and maybe this is a prime opportunity to help educate others with the same worry. This study was performed on a Point of Care (POC) test, not a diagnostic laboratory test. A test strip is what is was performed on. In the study, they found that 200ng/mL of biotin resulted in a False-Negative result. Up to 100ng/mL, zero interference. No issues. I dove into pharmacokinetics, and according to this particular study, (https://pubmed.ncbi.nlm.nih.gov/34736902/), it says: "In the 44 patients (6.3% of overall study cohort) who were documented as taking biotin supplements (range of doses, 2.5-10 mg/day), blood biotin levels ranged 0.9-21.3 ng/mL". Now, this is important. That is considered high doses of biotin, correct? So, if the cohorts were taking 2.5mg-10mg (2,500mcg-10,000mcg, respectively) and only were able to produce blood concentration levels of 0.9 to 21.3ng/mL, that wouldn't sniff the surface of interference. It's not happening. Also, if this is all boiled down to happening on a POC test strip, then what significance does that have on diagnostic laboratory tests? Especially ones that don't mention biotin-streptavidin as part of their testing strategy? Doctor, I believe it is time we admit that this is beyond ridiculous. What say you, expert?

Biotin-streptavidin indicator systems are used in many blood/serum/plasma diagnostic tests.  This is certainly true for tests using strips for diagnosis but it does also pertain to liquid format lab tests as well on some occasions.  Biotin is a normal part of the diet and many people take supplementary biotin but the idea that even supplementary biotin can lead to falsely negative blood tests is overblown.  To put this in context, I do not quiz my patients on whether or not they are taking supplements when I do blood tests and I have no concern that this is a meaningful problem for the vast majority of persons.  Too much has been made of the potential for biotin to impact test results.  While in science one can never say never because strange things do happen, I would not worry whatsoever about biotin effecting HIV test results.

All the best and stay well,

C.W

Enjoy your vacation. EWH