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Iron deficiency is the commonest cause of anaemia. Blood loss
Iron is best absorbed from the upper small bowel as ferrous state (Fe2+). It is transported across the intestinal cell and into the plasma. It Is carried to red cell in bone marrow by transferrin. Red cells have sTfR which can be measured in plasma
Clinical feature – atropihic tongue vs beefy tongue in B12 deficiency
Ferritin is an acute phase reactant – its level increases with active inflammation, in the same way as ESR, CRP. sTfR reflects the true state of iron stores
Iron overload – haemochromatosis and in conditions requiring frequent transfusions – serum iron and ferritin raised. TIBC is usually low.
Iron deficiency: Brittle nails
Koilonychia (spoon-shaped nails)
B12 def causes: most common – malabsorption. Small bowel disease: Crohn’s, coeliac disease
Reduction in IF – post gastrectomy OR pernicious anaemia
Pernicious anaemia – autoantibodies against gastric parietal cells and IF. Is an association with other autoimmune diseases (especially thyroid and Addison’s); Increased risk of gastric carcinoma
Schilling test – if test is still abnormal after giving IF? Problem likely to be in ileum. Cause? Could be bacterial overgrowth. Therefore give antibiotics
Absorption more rare cause unless wide spread disease as folate is absorbed in duo and jej
NEUROPATHY DOES NOT OCCUR
Intravascular haemolysis: low haptoglobins, haemosiderniuria
Red cells are destroyed in blood vessels and Hb released. Haptoglobins bind to free haemoglobin and escort to liver.
Haptoglobins become saturated and may be passed in urine or converted to haemosiderin. Alterantively, further reactions methaemalbumin in circulation
Polychromasia: “many colours” - blue tinge, caused by rRNA in young RBC and pink colour of Hb
G6PD deficiency affects all cells, but most severe in erythrocytes when pentose phosphate pathway provides only means of generating NADPH. Precipitating factors can cause symptoms with underlying G6PD deficiency e.g. Antibiotics, Antimalarials, Antipyretics
true (primary: PRV vs secondary: hypoxia: chronic smoking, altitude, lung disease; excess erythropoietin: renal cell ca, hepatocellular ca, polycystic kidneys) vs apparent (reduced blood volume)
Excess erythropoietin: renal cell ca, polycystic kidneys, adrenal ca, hepatocellular ca
Pancytopenia: sepsis, SLE, aplastic anaemia
AML: Inc blast cells dec mature cells
CML: Inc impaired mature
ALL: Inc lymphoblasts NO maturation
CLL: Inc mature abnormal, B- and T- cells
Pre-op assessment of bleeding
Lymphocytosis: primary (malignant clonal proliferation) vs secondary (infections: EBV, rubella, varicella zoster, TB; autoimmune)
1. B. Lymphocytosis. Many viral infections, including infectious
mononucleosis, cause a lymphocytosis.
2. H. Reticulocytosis. The administration of haematinics results in
a brisk increase in erythropoiesis with a transient rise in the
peripheral blood reticulocyte count.
3. A. Anaemia. There are several mechanisms that may result in
anaemia in patients with chronic renal failure, the most
important being a reduced production of erythropoietin. Other
mechanisms include iron deficiency due to blood loss from the
gastrointestinal or genitourinary tracts, folate loss into the
dialysate and shortened red cell survival.
4. G. Polycythaemia. Chronic hypoxia stimulates the production
of erythropoietin causing an increase in the red cell mass.
5. I. Thrombocytopenia. The intravascular coagulation depletes
peripheral blood of platelets.
· Most likely diagnosis: Pernicious anemia.A. The two most common causes of megaloblastic anemia are deficiencies of vitamin B12 or folate. These deficiencies decrease the synthesis of DNA, which results in nuclear-cytoplasmic assynchrony in maturation, which is the hallmark of megaloblastic anemias. This abnormal maturation will produce characteristic histologic changes in the cells in the peripheral blood, including oval macrocytes and hypersegmented PMNs, which are neutrophils with more than five lobes to their nuclei.
Most likely diagnosis: Infectious mononucleosis.
· Confirmatory laboratory tests:(1) Specific antibodies for Epstein-Barr virus (EBV) antigens (viral capsid antigens, early antigens, or Epstein-Barr nuclear antigen), (2) a positive heterophil reaction (monospot test), and (3) lymphocytosis with the characteristic atypical lymphocytes in the peripheral blood.
failure to thrive: poor weight gain and physical growth failure over an extended period of time
TIA: most common cause is an embolus that occludes an artery in the brain
Polycythaemia rubra vera presented with TIA as blood viscosity increased by increased red cells and platelets become adhesive
B12 deficiency. Peripheral neuropathy. Big and beefy tongue