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Bruise and bump after blood test. Hematoma?

Bruise and bump after blood test. Hematoma?

The following is an actual conversation between an iCliniq user and a doctor that has been reviewed and published as a Premium Q&A.

Medically reviewed by

Dr. Nithila. A

Published At July 13, 2019
Reviewed AtMay 28, 2024

Patient's Query

Hello doctor,

One week ago, my mother had a CBC done, and the results were all perfectly normal. However, the laboratory forgot to order a peripheral smear review (which her doctor requested). So a week later, the CBC was repeated with a smear.

Oddly, the results of this new CBC were,

1. Low WBC.

2. Low RBC.

3. Low neutrophils.

(The smear was normal).

At the time of this second laboratory draw, the laboratory technician commented this is going to bruise, and it did. A huge dark bruise and bump formed on my mother's arm very soon after the blood was drawn. I assume this is a hematoma. My question is, can a laboratory draw technique error (as evidenced by the large bruise and hematoma painful) be the cause or reason for the low WBC, low RBC, and low neutrophils? Please keep in mind the Smear result was normal (unremarkable). I should also point out that this CBC was manual (versus automated).

I know it is essential to repeat the CBC with smear again to verify, but I like to know if improper drawing or laboratory techniques could cause the odd results and if so, what the mechanism of action would be. I can show you her actual results, plus a photo of the bruise or hematoma.


Welcome to the icliniq.com.

I have reviewed your query and attached images as well. You are having superficial thrombophlebitis most likely as per given history and attached image. It can be most likely due to a technical error during collection. However, your low red blood cell count, low ANC, and the low total count could not be due to a technical fault. It can be temporary finding due to some unnoticed infection. I suggest you repeat CBC (complete blood count) after few days approximately after 7 to 10 days and it will come standard mostly.

Your peripheral smear examination report is normal, so no need to worry. You can revert with reports once done after a few days. For thrombophlebitis or bruise, I suggest you apply ice wrapped in thin cloth frequently like five to six times a day. Thrombophleb gel also can be beneficial. I hope I have answered your question. Let me know if you have another problem in mind.

Patient's Query

But I have read that things like improper draw technique could cause things like hemolysis or clotting - which can lead to low RBCs, for example? Is that not the case? Also - since the CBC differential was manual, could that cause the low neutrophils?

Hello, Welcome back. I can understand your concern and will help you by answering as much accurate as possible. Let me know you that improper venipuncture can lead hematoma formation but never lead to clotting of blood. The blood clotting occurs in vaccute if proper mixing of blood with anti coagulant not done by shaking the vaccute. The improper venipuncture sometime can lead hemolysis of collected blood but in that case CBC could not be possible and the picture reflected in peripheral smear examination report as well. In such case hemoglobin level also goes down. In such case prepared blood slide also shows changes in cells. So it could not be the cause in your case and pathologist can't make such a mistake. So don't worry about blood clotting and hemolysis as cause. The low red blood cells can be due to beginning of iron deficiency anemia because your hemoglobin level is borderline. I suggest you repeat CBC after few days as I have suggested, than will discuss further if any finding come back abnormal. Meanwhile for thrombophlebitis apply ice and mentioned gel as advised. If no improvement than consult her to nearby doctor for detailed evaluation. Hope I have answered your question. Let me know if I can assist you further. Best regards.

Patient's Query

This might help to know - her Iron Levels were off... her Total Iron was slightly elevated, and % Saturation also slightly elevated... what could that mean. Ferritin was normal.
Hello, Welcome back. Can you provide numerical values of all iron profile report??? I have to check how much elevation of transferrin saturation is present?? So either you can attach report or provide numerical values.. Kindly Also let me know is this iron reports done from same sample collected for CBC?? Regards

Patient's Query

Yes, I've attached her comprehensive results from one week ago... as a reminder, these results were drawn and included everything EXCEPT the smear review which the lab forgot to draw. So we repeated just the smear a week later (which you've already seen). Her medical history is cancer in 2015 (fallopian), and she's in what we believe remission for the past 4 years - she feels fine, and these labs were all part of her routine follow-up. Her VEGF is always a bit low because she takes supplements to help keep these levels low. Thanks for having a look at everything.
Hello, Welcome back to the icliniq. Com I have read the attached report. In attached report total iron binding capacity and ferritin are within limit. Transferrin saturation and serum iron level elevated slightly. Now it doesn't indicate to any specific hematological problem. Usually in case of iron overload transferrin saturation increases. But in that case ferritin level also should be raised which is normal here. So these finding could be due to some iron containing supplement intake or some error while running it analyzer. It doesn't need to be concerned much as other values doesn't favour iron overload. Hope I have answered your question. Let me know if I can assist you further. Regards

Patient's Query

So your other comment previously... that her almost low hemoglobin in the LATEST CBC (the one that was unusual) could be due to iron deficient anemia - that wouldn't be the case then, since her iron levels were normal (and even a little bit high)? Also - now that you've seen the comprehensive labs from the week prior to this, including the very normal CBC - do you think the new CBC could be due to lab error? Given they were only 7 days apart and the "proof" that something wasn't right given the large hematoma? Or do you still feel that the newest CBC is likely correct - she did truly develop low WBCs, low RBCs, and low ANC in a week's time? (You mentioned infection, but she has no symptoms of that.) Thanks again!
Hello, Welcome back to the icliniq. Com Initially I was thinking iron deficiency anemia. But iron profile reports not suggestive of any iron deficiency anemia.so iron deficiency anemia might not be the cause. The low white blood cells count sometime can be due to unnoticed infection or some drugs. She is using medication to lower VEGF. So it can decrease total count. However we cannot neglect laboratory error as well. The development of large hematoma with superficial thrombophlebitis could be in favour of some technical error as well. Rather thinking all that I suggest repeat CBC after week. If still values abnormal than we w'll discuss further. Hope I have answered your question. Let me know if I can assist you further. Regards

Patient's Query

Hi, Welcome back. I can understand your concern raised!!! In 1 vaccute 2 ml blood is collected. So in 14 tubes maximum 28 to 30 ml blood collected. Such minor loss of blood can't decease red blood cells and WBC. In phlebotomy around 300 ml blood withdrawal. So it cannot be called phlebotomy in any way. So your blood collection is not related low red blood cells. Hope I have answered your question. Let me know if I can assist you further. Best regards.

Same symptoms don't mean you have the same problem. Consult a doctor now!

Dr. Goswami Parth Rajendragiri
Dr. Goswami Parth Rajendragiri


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