Vitamin B12 and Folate Deficiency: Who to test? How to manage? - PowerPoint PPT Presentation

Loading...

PPT – Vitamin B12 and Folate Deficiency: Who to test? How to manage? PowerPoint presentation | free to view - id: 84635b-OGJiN



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Vitamin B12 and Folate Deficiency: Who to test? How to manage?

Description:

Vitamin B12 and Folate Deficiency: Who to test? How to manage? Nicole Priddee Consultant Haematologist RIE 08/11/12 Overview Folate Intake and absorption Consequences ... – PowerPoint PPT presentation

Number of Views:137
Avg rating:3.0/5.0
Slides: 20
Provided by: couk
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Vitamin B12 and Folate Deficiency: Who to test? How to manage?


1
Vitamin B12 and Folate Deficiency Who to
test? How to manage?
  • Nicole Priddee
  • Consultant Haematologist RIE
  • 08/11/12

2
Overview
  • Folate
  • Intake and absorption
  • Consequences and causes of deficiency
  • Who to test? How to treat?
  • Vitamin B12
  • Intake and absorption
  • Consequences and causes of deficiency
  • Who to test? Who to treat? How to treat?

3
Folate and B12 use
  • DNA synthesis

4
Folate Intake and Absorption
  • Leafy vegetables and animal products
  • RDA
  • Normal 200-400 mcg Pregnant 600mcg Lactation
    500mcg
  • Total body stores 5-10mg
  • Absorbed in jejunum
  • Enters cells via folate receptor and cannot
    diffuse back into plasma

5
Consequences of Folate Deficiency
  • Megaloblastic anaemia
  • Thrombocytopenia
  • Leucopenia
  • Hypersegmented neutrophils
  • Neural tube defects

6
Causes of Folate Deficiency
  • Inadequate intake
  • Poor nutrition alcoholism
  • Increased consumption
  • Pregnancy haemolytic anaemia
  • Impaired metabolism
  • Drugs (trimethoprim, phenytoin, methotrexate)

7
Who to test for Folate Deficiency?
  • Patients with
  • Macrocytic anaemia
  • Unexplained pancytopenia
  • Typical blood film changes
  • Poor diet or malnutrition
  • Small bowel disease or resection

8
Testing for Folate Deficiency
  • Serum folate
  • Easy to perform
  • Sensitive to recent dietary intake
  • Falsely low if recent reduction in dietary intake
    or alcohol binge
  • Red cell folate
  • More labour intensive and difficult to reproduce
  • Measure of folate stores
  • Falsely normal if recent blood transfusion

9
How to treat Folate deficiency?
  • Confirm deficiency
  • Address nutritional and lifestyle issues
  • Folic acid supplements (ensure not B12 deficient)

10
Vitamin B12 Intake
  • Animal products are only dietary source
  • Average daily intake 5-7 mcg
  • RDA
  • Normal 2mcg Pregnancy/ lactation 2.6 mcg
  • Total Body Stores 2-5mg ? ½ in liver

11
Vitamin B12 Absorption
  • Adequate B12 intake
  • Acid-pepsin in stomach
  • Pancreatic proteases
  • Gastric secretion of IF
  • Ileum with functional vitamin B12- IF receptors

12
Consequences of Vitamin B12 Deficiency
  • Megaloblastic anaemia
  • Thrombocytopenia
  • Leucopenia
  • Hypersegmented neutrophils
  • Neurological symptoms
  • Sensory symptoms, impaired dexterity, Subacute
    combined degeneration of the cord
  • Neuropsychiatric symptoms
  • Memory loss, personality changes, dementia

13
Causes of Low B12 levels
  • Pregnancy
  • Increased plasma volume and fetal absorption
  • COCP use
  • Reduced haptocorrin

14
Causes of B12 Deficiency
  • Dietary - vegans/vegetarians
  • Pernicious anaemia
  • Gastrectomy/ Gastritis/ Bariatric Surgery
  • Small bowel disease
  • Pancreatic disease
  • Drugs
  • PPI, metformin

15
Who to test for B12 Deficiency ?
  • Patients with
  • Macrocytic anaemia
  • Unexplained pancytopenia
  • Typical blood film changes
  • Unexplained neurology
  • Dementia
  • Poor diets or malnutrition, vegans
  • Small bowel disease or resection
  • Bariatric Surgery
  • Glossitis

16
Who to treat?
  • Haematological abnormalities
  • Neurological symptoms
  • Clear deficiency
  • True vs apparent? What cut-off?
  • Active B12
  • Prophylaxis
  • Vegans/ vegetarians esp in pregnancy
  • Gastric surgery

17
How to treat?
  • Address cause, if possible
  • IM Vitamin B12 (Hydroxocobalamin)
  • Preferred option
  • Better absorbed, fewer compliance issues
  • Oral cyanocobalamin
  • Vegans
  • Anaphylaxis to IM or unsuitable for IM injections

18
References
  • Carmel, R (2008) How I treat cobalamin (vitamin
    b12) deficiency. Blood 112(6)2213-21.
  • Schrier, SL (2012) Diagnosis and treatment of
    vitamin b12 and folic acid deficiency. Available
    from http//www.uptodate.com/contents/diagnosis-an
    d-treatment-of-vitamin-b12-and-folic-acid-deficien
    cy?sourcesearch_resultsearchb12deficiencysele
    ctedTitle17E150 Accessed 05/11/12
  • Schrier, SL (2012) Etiology and clinical
    manifestations of vitamin B12 and folic acid
    deficiency. Available from http//www.uptodate.com
    /contents/etiology-and-clinical-manifestations-of-
    vitamin-b12-and-folic-acid-deficiency?sourcesearc
    h_resultsearchb12deficiencyselectedTitle27E1
    50 Accessed 05/11/12
  • Schrier, SL (2012) Physiology of vitamin B12 and
    folic acid deficiency. Available from
    http//www.uptodate.com/contents/physiology-of-vit
    amin-b12-and-folic-acid-deficiency?sourcesearch_r
    esultsearchb12deficiencyselectedTitle57E150
    Accessed 05/11/12

19
Questions?
About PowerShow.com