1. Vitamin B12:Anemia Mousa’ab Abdulrhman R. R

2. So how do we start !

3. 36 years male presented to the clinic with
3 month history of tiredness and SOB after Jogging

4. Basics
Hx
P/E
Dx
Tx

5. Anemia Pathophysiology Classification
Basics
Hx
P/E
Dx
Tx

6. Fact
Most common cause of anemia is blood loss

7. Basics

8. Function Of Vitamin B12 :
Important for metabolism.
Formation of red blood cells .
Maintenance of the central nervous system..

9. Folate Vs B12
Etiology Arrest of Erythrocyte Mutation Arrest of Methonoin Formation
Within Months Within Years
Onset
Symptoms of Anemia Symptoms of Anemia
Presentation
Never Neurological Neurological Symptoms Are Common
Lab
Folate decrease B12 decrease
Homocysteine Decrease Increase
Methylmalonic Acid WNL Increase

10. Fact
Folic Acid Supplement Can Mask Vitamin B12 Deficiency

11. Basics
Hx
P/E
Dx
Tx

12. Fact Supplement !
Vitamin B12 is naturally available for human use only
through ingestion of animal proteins. Unfortified plant-
based foods do not contain vitamin B12.

13. Fact Vit B12 daily Consumption
The dietary reference intake for an adult ranges
from 2 to 3 µg per day

14. Fact
Vit B12 “cobalamin” , is a water-soluble vitamin

16. Basics
Hx
P/E
Dx
Tx

17. Fact Decreased absorption/Interactions!
Aminosalicylic acid can reduce oral vitamin B12 absorption,
Excessive alcohol intake
Reduced vitamin B12 levels may be more common with PPIs than with H2-blockers
Folic acid particularly in large doses
Anticonvulsants Phenytoin, phenobarbital
Nitrous oxide
Nicotine
Neomycin
Metformin (Glucophage)
Hormonal contraception

18. Most likely Populations to Get B12 Deficiency
Basics
Hx
P/E
Dx
Tx

19. Fact Ask about Drugs !
Oral contraceptive users generally have lower
serum vitamin B12 levels than nonusers

20. Fact Ask about Diet !
Nursing infants of mothers who adhere to a
strict vegetarian or vegan diet throughout their
pregnancy and while breastfeeding might also
experience serious B12- related deficiency
effects ,Even when the mother is not anemic or
symptomatic in any way.

21. Basics
During a checkup for HTN, a 65-year-old
Hx female reports a 2-month history of
tiredness, feeling faint from “getting up
too fast”, and “memory problems”.
P/E
Dx
Tx

22. Fact
All patients newly diagnosed with unexplained
cognitive decline or dementia should be
assessed for a possible vitamin B12 deficiency

23. What may lead to depletion and deficiency?
Basics
Hx
P/E
Dx
Tx

24. Fact
Pernicious anemia is an autoimmune disease in
which antibodies attack gastric cells, resulting in
impaired production of intrinsic factor that is critical for
absorption of vitamin B12.

25. Fact
Pernicious anemia, is the most common cause
of B12 deficiency WorldWide , but In the US,
most cases of vitamin B12 deficiency are due to
malabsorption.

26. Surgical
Procedure
Ileal resection
>20 Cm

27. Fact During Surgery !
Nitrous oxide causes the inactivation of vitamin
B12, which might result in acute hematologic or
neurologic complications of vitamin B12 deficiency.
Because nitrous oxide is a commonly used
anesthetic in surgery, people at risk (e.g., the
elderly) should be monitored for a developing
symptomatic vitamin B12 deficiency.

28. Bariatric
surgery

29. Fact
No single symptom, or cluster of symptoms, has
been uniquely associated with inadequate levels
of vitamin B12.

30. Fact The Most Common
Today, megaloblastic anemia is most likely
due to a vitamin B12 deficiency until proven
otherwise

31. What are the symptoms of B12 deficiency?
Basics
Hx
P/E
Dx
Tx

32. Basics
Hx
P/E
Dx
Tx

33. Basics
Hx Neuropathy
Chronic
P/E Distal & Symmetrical, Usually Legs First
Common in Alcoholic
Dx Sensory + Motor
Tx

34. Vit B12 is Common e.g of Metabolic Neuropathy

35. Who should be Tested For B12 deficiency?
Basics
Hx
P/E
Dx
Tx

36. Order:
Basics Complete blood count (CBC)
Peripheral blood smear
Serum cobalamin (B12)
Hx
Not all patients with a
vitamin B12 deficiency will
have hematologic
P/E manifestations.
Dx
a low serum B12 level does not
automatically mean a deficiency.
Tx

37. Fact Falsely low values !
have been associated with :
Multiple myeloma
Oral contraceptives
Folate deficiency
Pregnancy

38. Fact Falsely Normal values !
have been associated with :
Liver disease
Myeloproliferative disorders
Polycythemia vera
Renal insufficiency Essential thrombocytosis
Myelofibrosis
Chronic myelogenous leukemia (CML)
So it is important to evaluate further.

39. Basics
So What To do ?
Hx
Complete blood count (CBC)
Peripheral blood smear
Serum cobalamin (B12)
P/E
Dx
Are Not Specific , Nor Accurate
Tx

40. Confirmatory Testing
By far, the most common, accurate, and widely used
confirmatory tests for identifying vitamin B12 deficiency are
tests for......
Homocysteine (Hcy) Methylmalonic Acid (MMA)
is a sensitive indicator for a vitamin B12 deficiency
low levels of vitamin B12 increases in total serum Hcy.
Shilling Test
Differentiate b/w Nutritional B12 def. vs IF
Not Used Anymore !

41. Basics
Hx
P/E
Dx
Tx

42. Basics There is no gold standard for determining
cobalamin deficiency.
Hx
P/E
Dx
Tx

43. Prevention !
To prevent a vitamin B12 deficiency, you should advise all
patients 51 years of age or older to consume synthetic
vitamin B12 daily. Dosage recommendations vary.

44. Fact
High vitamin B12 level in elderly individuals may
protect against brain atrophy or shrinkage associated
with Alzheimer's disease and impaired cognitive
function

45. Basics
Hx
P/E
Dx
Tx

46. Fact Adverse Effect !
Vitamin B12:
has extremely low toxicity and even
taking it in enormous doses appears not to
be harmful to healthy individuals.

47. Fact Replacement
Cobalamin replacement is effective because
crystalline forms of B12 can be absorbed even
when animal protein-bound forms cannot be
digested.

48. Fact
Vitamin B12 is used to treat :
Vitamin B12 deficiency
Cyanide poisoning
Hereditary deficiency of transcobalamin II.

49. Vitamin B12 is Not carcinogenic, teratogenic, or mutagenic
It is considered safe even at 1,000 times the RDA.