[Question #10982] "Collected” time different from the time blood was drawn

18 months ago

Dear Doctors,

I took a 4th generation hiv test at Carbon Health, and the test was done by Quest Diagnostic. The result was negative but I found the "collected" time on this report is different from the time when my blood was actually drawn. My blood was drawn at 10am, but the on the report the “collected" time is 4pm. I am so confused. I don't know if the report is about my own blood.

Edward W. Hook M.D.

18 months ago

Welcome back to the Forum. I cannot comment on the discrepancy and would suggest that you call Quest and ask about this. My guess however is that the term "collected" includes the transit time for your specimen to get from Carbon Health to the lab, i.e. transit time and is the time that the specimen was received in the laboratory for testing. It is not unusual for specimens to take several hours between the time they are collected and the time they are received in the lab. I am confident that it was your blood that was tested- labs are VERY careful about this. EWH---

18 months ago

Dear Dr Hook,

Thank you for your response. I still have questions about the used needle thing (it was stated in my pervious question #10876). I know according to the regulations, a nurse should never reuse needles, but I just worried about the nurse might make a mistake. So could you please think about the worst thing with me: I was infected long time ago. And the nurse indeed reused the needle. The blood in the soft tube was not mine, but a healthy person’s. In this scenario, I wonder if there is a possibility that the healthy people’s blood entered my vacutainer with my blood and caused my results to be false negative?

Edward W. Hook M.D.

18 months ago

I will not repeat the reassurances I provided in the past about the virtual impossibility of your having had your blood drawn with a used needle. I suspect that you know intellectually that your concern is unfounded. Further, I have told you above how to resolve your concerns about your blood being switched. Further if a person had HIV (you do not) and their blood was mixed in a vacutainer tube with the blood of a person how had HIV- the test would still be positive.

You are worrying needlessly. EWH

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18 months ago

Thank you Dr Hook. Your answer is a relief to me. Just a quick question is “person how had hiv” a typo? Do you mean “person doesn't have hiv”?

Edward W. Hook M.D.

18 months ago

Sorry, there was a minor typo in the sentence which should have read- "Further if a person had HIV (you do not) and their blood was mixed in a vacutainer tube with the blood of a person who had HIV- the test would still be positive." Two letters were switched.

Please don't worry. I am confident that you do not have HIV and that the test results you received were yours. EWH

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18 months ago

Thank you doctor, but you may misunderstand my question. I wonder if I was infected a long time ago, and my blood mixed with a healthy person's blood, will my result still be positive? I just afraid that my result may be false negative.

Edward W. Hook M.D.

18 months ago

I understood you did not understand my reply. IF you had been infected for a long time you would have a positive test. If your blood was then mixed with the blood of an uninfected person, the test would still be positive. The test is so sensitive that mixing with another person's blood would not change the result. It would NOT be falsely negative.

Let me point out that the scenario you describe above is a rather paranoid "what if" question which has no factual basis. You are worrying unnecessarily.

As you know we provide up to 3 responses to each client's question. This reply completes this thread which will be closed shortly. You should not need to return regarding the concerns you mention above. EWH

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18 months ago

This is the scenario I want to ask about: I was infected long time ago. And the nurse indeed reused the needle. The blood in the soft tube was not mine, but a healthy person’s. In this scenario, I wonder if there is a possibility that the healthy people’s blood entered my vacutainer with my blood and caused my results to be false negative?

Edward W. Hook M.D.

18 months ago

Already answered. The scenario you describe is no scientifically possible. Please accept your result.

In my opinion, the best thing you could do is to seek professional counseling to help you work through your inappropriate and unjustified concerns. This thread is now over. EWH

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