RBC number is not necessarily reduced in anemia, thus it is not a reliable anemia marker. But is a reduced count irrelevant, when both Hb and Ht are normal? For instance, let's consider a patient with increased MCV(113) and MCH(34), normal Hb/Ht, a reduced RBC count and low serum B12. Does the low RBC count constitute evidence of (megaloblastic) anemia or is it just a macrocytosis case? Of course, this is not an important distinction therapeutically(B12 inj. are necessary in both cases).
HI Romanos. Are the reported numbers (MCV 113; MCH 34) only an example or a case? Theoretically, a great MCV increase depends on a very important dyserythropoiesis for a long time. So, is not possible to be an RBC's decrease without a parallel decrease of both Hb and Ht. In these cases the higher volume as well as the higher Hb content in each RBC cannot to balance the decreased RBC number
Thank you for your reply. Actually, it is an example based on a case. My thought on the case was what(I think) you described at the end of your message: that the patient was indeed anemic, but the increased hemoglobin content in the (fewer) red blood cells resulted in a false normal Hb level. The increase in RBC volume could theoretically explain the normal Ht. You're saying it couldn't.
Edit: in the real case, MCV was 112,9 fl /MCH was 39,5 pg/ RBC 3.310.000/mm^3
We must consider that the increase of cellular volume as well as of cellular Hb content (MCH) are the pathophysiological attempt to compensate the decreased RBC production due to reduced B12 availability. The total hemoglobin begins to decrease when the increase in MVC and MCH cannot more balance the reduction of RBC number. In addition, anemia can be better defined as "decrease of individual HB level": by using this definition, you can delete all uncertainties arising from many different reference values that we can find in literature. In your "real case" the HB amount is 131g/L and Ht is 0,374 L/L (3.310.000 x 39,5 and x 112,9, respectively). How much decreased the Hb level in the last mounths?
The patient's Hb level has remained the same through the last three years; she is not anemic, not even by her own standards.
The point I'm trying to make is this: B12 deficiency can present as a macrocytic anemia or mere macrocytosis, with normal RBC count/Hb/Ht; maybe this patient has something in between, in terms of disease progression; a kind of ''compensated'' macrocytic anemia. And maybe a low RBC count with elevated MCV and MCH represent an intermediate stage of B12 deficiency disease progression, following mere macrocytosis and preceding macrocytic anemia.
You're describing an "absurd pathophysiologic", Romanos! If we have a B12 deficiency, the RBCs number decreases and MCV increases. If we have a deficiency, we need B12 supplementation. As a result, reticolocytes begin to increase and MCV decreases. What B12 levels had your patient? What B12 level has now? An "intermediate stage of B12 deficiency disease progression" before the conclamate anemia can theoretically to be present, but not during three years! Remember: an anemia that not responds to therapy is a "refractory" anemia! Do you have considered an alternative diagnosis, MDS in primis? How old is your patient? It was evaluated the possibility of a CDA (Congenital Dyseriythropoietic Anemia) that can occur even in the youngs adult?
You misunderstood what I wrote, I think. The macrocytosis along with the low RBC count are very recent findings. Judging by the patient's CBCs over the past three years, her Hb levels have remained the same and thus, she cannot be considered anemic, even by her own Hb levels.
Following B12 administration, the patient's CBC indices have returned to normal. This is not a diagnostic dilemma; rather, it is my trying to lay out a theoretical concept.
B12 deficiency can present as macrocytosis(mere MCV elevation). It can also present as megaloblastic anemia. What if this patient's presentation(elevated MCV/MCH, low RBC count, normal Hb/Ht) represents an intermediate stage of disease progression, when the bone marrow can still compensate for the deficient erythropoiesis?
What perplexes me is that the macrocytosis in B12 deficiency is the result of impaired differentiation, rather than the result of the marrow's attempt to counterbalance the deficiency. Therefore, whatever compensation we believe we are witnessing could not possibly be attributed to a physiologic reaction. It seems to be a collateral correction.
Can I have normal hemoglobin and low red blood cells in the case
- Badges
- Science topic
- Similar topics
- Data Mining
- Classification