Macrocytic Anaemia. Elliot Catchpole PCMD. Recap. Mean Cell Volume = The size of each RBC. MACROCYTIC >96. Normocytic 76-96. Microcytic <76. Haemolysis. Non- Megaloblastic. -IRON deficiency Thalassaemias Sideroblastic. -Alcohol -Liver Disease - MYLODYSPLASIA. -G6PD Deficiency
-Paroxysmal Nocturnal Haemoglobinurea
Purines/pyrimadines = DNA synthesis
Includes B12 and folate – will show megaloblasts (large and immature cells) due to poor DNA synthesis. These cells are large because B12/folate deficiency result in impaired DNA synthesis, so cells are stuck in the G2 phase of mitosis and carry on growing, so become large and fragile. Cytoplasm/cell contents will be disproportionate to the DNA. This is different from reticulocytes.ALSO will show hypersegmentedneutrophils – these have more than 4 nuclei (4 is normal) due to slowed DNA synthesis.They can be seen on a peripheral smear.
In contrast, alcohol and liver disease do not fall under this category.
Pregnancy and hypothroidism can also cause a mild non-megaloblastic macrocytosis.
MCV = Raised
Stores deplete very very slowlyDietary – VeganismPERNICIOUS ANAEMIA
Stores deplete quickly in monthsDietary – leaFy green vegetables Cell turnover – e.g. In SCD or psoriasis
NEUROLOGICAL SYMPTOMS- Most common = peripheral neuropathy
NO NEUROLOGICAL SYMPTOMS
B12 HomocysteineMethylmalonic AcidAnti parietal/IF antibodies
Folate HomocysteineMethylmalonic Acid
SUBACUTE COMBINED DEGENERATION OF THE CORD
Increased CVS risk(high homocysteine)
Treat with B12
The Patient is given appropriate therapy (which is????). She returns a month later. Although she noticed improvement, she still doesn't feel back to normal. She is starting to feel tired again and slightly breathless on exertion. Bloods show?Hb = 7.5MCV = 70