Vitamin b12 and folate deficiency Flashcards
what is anaemia
whats normal range?
decreased hb levels
varies with sex, gender and ethincity
signs and symptoms and specific signs due to anemia
signs
pallor(due to decreased oxygyHB and bf shunted to vital organs instead of peripheral surface)
tachycardia (due to heart compensating)
tachypnoae (to makeup for decreased o2 b decrased hb)
systolic flow murmur (d to changes in b flow)
hypotension ( if cause of anemia is v rbc)
symptoms
headaches/claudication ( pain due to little b f to leg)/ angina / weakness/confusion/lethargy
specific signs d anaemia
kolionychia (spoon shaped nails in dented d iron defieceny)
glossitis (inflammation and depapilation of tongue)
abnormal facial bone development ( rare d thalassaemia)
angular stomatitis (inflammationof the corners of the mouth d iron deficieny)
possible reasons why anaemia may develop?
- BONE MARROW (reduced or dysfunctional erythropoetin/ abnormal globin chains synthesis/ abnormalhaem synthesis)
- RBC (abnormal structure/abonormal metabolism/mechanical damage)
- SPLEEN (increased removal)
— side note = excessive bleeding
EPO function normal
reduced/ dysfunctional erythopietin causes
- kidney makes erythropeitin due to hypoxia (detects it) sends it to the bone marrow which binds to receptors on erythoblasts in bone marrow and stimulate it to make RBC so ^ RBC in blood
POSSIBLE CAUSES
- kidney disease = cant detect changes in b o2 level so doesnt produce erythropetin
- bone marrow not responsing to EPO due to parovirus infection /chemo/toxic
- marrow is infiltated by cancer or fibrous tissue so haemotpoetic cells reduced in number
- anaeia of chronic diseas e.g. rheumatoid arhtiris where FE2+ not made available in the bone marrow
- rare forms of blood cancers myelodysplastic syndromes abnormal clones of marrow stem cells limit capacity of RBC and WBC
defects in the Hb sythesis
- insuffiecnt iron intake
- anaemia of chronic disease can result in function iron deficiney (RA)
- mutatuions in the genes coding the globin proteins a b thalassemia / sickle cell disease
- defects in the haem synthesis pathway can cause sideroblstic anaemia (body has enough iron but cant use it)
how do abnormal structure and mechanilical damage cause haemalolltyic anaemis
inheritied = genes muations that code for cytiskeletons nad pasma membrane so less flexible more likelt to rupture so less RBC e.g. hereditary spherocytosis
aquired = microangiopathic haemoltyic anaemia d mehcnaincal stress (small bv loss RBC)
defects in RBC metabolism
G6PDH deficiency NADPH to prevent formation of heinz bodies
pyruvate kinase deficiency = so less pyrvuate so overall deficiency of ATP undergo haemolysis
excessive bleeding
- loos RBC
- injury/childbirth/
- chronic NSAID usgage damages GIlining causign it to bleed
- chronic bleeding e.g haemorrhoids/UC/ diverticulosis/tumors/polyps/heay menstrual bleeding
reticuloendothelial system
2 ways to remove RBC
(RBC lysis in and release hb into palsma/ go to spleen)
-sutoimmune disease
extramedulaary hamopeiss
too much depand or mutated bone marrow porgenitor cells can go to spleen and liver and cause it to make RBC
2 features to work out cause of aneamia
size of RBC
prescence or absence of reticulolysis (immature RBC , it shows whether bone marrow is working)
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folate
made by bacteria and plants
green leafy vegtables
absorbed in the jejnum and duodenum
converted to tetrrahydrofolate FH4 by intestinal cells
taken up by liver which stores it for 3-4 months enogh
needed for DNA synthesis
folate deficency
causes
symptoms
who do we give it to
deitary intake poor / preganct / increased erhtyropietisis / severe skind diseae ?/ alcholisms b damage to intestinal cells / liver diseaseand heart failure cause urinary loss of folate
anaemia like related/ depression/muscle weakness/diarrrhoae.numbnes and tingling of the feet/reduced taste
prganct ladies igiven 400microg/day 2 weks before conception and durign first 1st 2 weeks because important for neural development
vitamin b12
cyanocobalamin
water soluble
essential cofactor of RNA synthesis so needed for erythopoesis ,
needed for cNS functioning
made by bacteria good sources = milk, egg/cheese/meat/yeast extract
