Iron Deficiency Anaemia Flashcards
What is the major cause of a microcytic, hypochromic anaemia, in which the two red cell indices, mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH), are reduced and the blood film shows small (microcytic) and pale (hypochromic) red cells?
Iron deficiency
What is the major differential diagnosis of a microcytic, hypochromic anaemia?
Thalassaemia and Anaemia of Chronic Disease.
The transport of iron is largely dependent on which three proteins?
- Transferrin
- Transferrin receptor 1 (TfR1)
- Ferritin
Fill in the blanks. “Transferrin molecules can each contain up to ________ of iron.”
Two (2)
Where are red blood cells broken down?
In the macrophages of the reticuloendothelial system.
Where is iron incorporated into haemoglobin?
Erythroblasts in the bone marrow.
Fill in the blanks. “Some iron is stored in the macrophages as ___________ and _______.”
Ferritin and Haemosiderin
True or False? Hemosiderin is a water soluble protein- iron complex.
FALSE!! It’s Ferritin .
What is the name given to the outer protein shell for Ferritin?
Apoferritin
What is the make- up for Ferritin?
22 subunits and an iron–phosphate–hydroxide core.
True or False? Ferritin is visible by light microscopy.
FALSE!! It is NOT visible by light microscopy.
Fill in the blanks. “ ___________ an insoluble protein–iron complex of varying composition containing approximately 37% iron by weight.”
Hemosiderin
True or False? “Iron in the form of Ferritin and Hemosiderin is in the Ferrous form.”
FALSE!! It is in the Ferric form.
True or False? Hemosiderin is visible in macrophages and other cells by light microscopy after staining by Perls’ (Prussian blue) reaction).
TRUE!!
Where is Hemosiderin derived from?
It is derived from Partial lysosomal digestion of ferritin molecules .
What is the name of the enzyme that catalyses oxidation of the iron to the ferric form for binding to plasma transferrin?
Caeruloplasmin ( copper- containing enzyme)
What is the average amount of iron found in Haemolglobin in the MALE adult?
2.4 grams / 65 %
What is the average amount of iron found in Ferritin and Haemosiderin in the MALE adult?
1.0 (0.3–1.5)/ 30 %
What is the average amount of iron found in myoglobin in the MALE adult?
0.15 grams/ 3.5 %
What is the average amount of iron found in Haemoglobin in the FEMALE Adult?
1.7 grams/ 65%
What is the average amount of iron found in Ferritin and Haemosiderin in the FEMALE adult?
0.3 (0–1.0) / 30 %
What is the average amount of iron found in myoglobin in the FEMALE adult?
0.12 grams / 3.5 %
What amount is the daily absorption of iron?
1 mg
What amount is the daily loss of iron?
1mg
Which organ of the GI system is iron absorbed?
In the duodenum
Fill in the blanks. “ Iron overload causes a RISE in _________.”
Tissue Ferritin
Fill in the blanks. “ Iron overload causes a FALL in ________ & _________.”
Transferrin receptor 1( TfR1) and Divalent metal transporter 1 (DMT‐1)
Fill in the blanks. “ In Iron deficiency there is a FALL in _________ &__________.”
Ferritin & δ‐aminolaevulinic acid synthase (ALA‐S)
Fill in the blanks.” In Iron deficiency there is a RISE in __________.”
Transferrin receptor 1 ( TfR1)
Hepcidin is produced by which organ cells?
Liver cells
What is the name given to the enzyme that digests membrane-bound Hemojuvelin (HJV)?
Matriptase 2
What are the two proteins secreted by Erythroblasts?
Erythroferrone and GDF 15
What is the major hormonal regulator of iron homeostasis ?
Hepicidin
What are the factors favouring iron absorption?
- Haem iron
- Ferrous form iron (Fe2+)
- Acids ( Hcl + Vitamin C)
- Solubilizing agents (ex sugars, amino acids)
- Reduced serum hepcidin
6.Ineffective erythropoiesis - Pregnancy
- Hereditary haemochromatosis
What are factors reducing iron absorption?
- Inorganic iron
- Ferric form ( Fe3+)
- Alkalis ( antacids, pancreatic secretions)
- Precipitating agents – phytates, phosphates, tea
- Increased serum hepcidin
- Decreased erythropoeisis
- Inflammation
What is the function of Hepcidin?
It inhibits iron release from macrophages, from intestinal epithelial cells and from other cells by its interaction with the transmembrane iron exporter, ferroportin.
It accelerates degradation of ferroportin protein
True or False? An INCREASE in Hepcidin levels REDUCES Iron absorption.
TRUE!!
What are the factors that stimulate hepcidin synthesis?
Cytokines circulating in inflammation
Diferric transferrin
What is the name of the substance secreted by erythroblasts which suppress BMP-mediated signalling for hepcidin secretion ?
Erythroferrone
True or False? Hypoxia SUPRESSES Hepcidin synthesis whereas in inflammation interleukin 6 (IL-6) and other cytokines INCREASE hepcidin synthesis.
TRUE !!
What are the factors that inhibit Hepcidin synthesis?
Hypoxia
Erythropoeisis
Where is iron normally absorbed?
In the duodenum
What is the name of the transporter at the basolateral surface controls the exit of iron from the cell into portal plasma?
Ferroportin
What additional organs is Ferroportin located in?
Heart
Kidney
Brain
Placenta
What is the name of the enzyme present at the enterocyte’s apical surface converts iron from the Fe3+ to Fe2+ state?
Ferrireductase
What is the name of the enzyme converts Fe2+ to Fe3+ at the basal surface prior to its binding to transferrin.
Hephaestin (ferrioxidase)
What is the total iron requirement for the Pregnant patient?
1.5-3
What is the total iron requirements for the menstruating female?
1-2
What are the clinical features of Iron deficiency anaemia?
- General signs and symptoms of Anaemia
- Painless glossitis
- Angular stomatitis
- Brittle, ridged or spoon nails (koilonychia)
- Unusual dietary cravings (PICA)
Neonatal Iron deficiency - cognitive and behavioural abnormalities, while in children it can cause irritability, poor cognitive function and a decline in psychomotor develop- ment.
What is the dominant cause of iron deficiency anaemia in developed country?
Chronic Blood Loss - especially uterine or from the gastrointestinal tract
How much iron is contained in 500ml of blood?
250 mg
What type of cells are found in iron deficiency anaemia ?
- Hypochromic, microcytic cells
- Target cells
- Pencil-shaped poikilocytes
True or False? In iron deficiency anaemia , the Reticulocyte count is increased while the platelet count is decreased.
FALSE!! The Reticulocyte count is LOW
Platelet count is INCREASED
What is the difference between iron deficiency anaemia and Anaemia of Chronic disease.
- In iron deficiency anaemia the SERUM IRON IS DECREASED while the TIBC IS INCREASED. but in Anaemia of Chronic disease both the Serum iron and the TIBC is BOTH REDUCED.
- In iron deficiency anaemia the SERUM FERRITIN IS LOW while in Anaemia of Chronic disease the SERUM FERRITIN IS NORMAL OR RAISED.
An increase in serum ferritin normally indicates?
It indicates iron overload or excess release of ferritin from damaged tissues or an acute phase response (e.g. in inflammation).
What is the most common cause of iron deficiency in men and post menopausal women?
GIT blood loss
Which test can be used to determine Gluten - induced enteropathy ?
- Test for transglutaminase antibodies
- Duodenal biopsy
What are the causes of Iron deficiency Anaemia?
- Chronic blood loss
- Uterine
- Gastrointestinal, e.g. peptic ulcer; oesophageal varices; aspirin (or other non-steroidal anti-inflammatory drugs) ingestion; gastrectomy; carcinoma of the stomach, caecum, colon or rectum; hookworm; schistosomiasis; angiodysplasia; inflammatory bowel disease; piles; diverticulosis.
- Rarely, haematuria, haemoglobinuria, pulmonary haemosiderosis, self-inflicted blood loss
- Increased demands (see also Table 3.3)
- Prematurity
*Growth
- Pregnancy
- Erythropoietin therapy
- Malabsorption
- Gluten-induced enteropathy, gastrectomy, autoimmune gastritis.
- Poor diet
Which staining method can the bone marrow be assessed to determine iron deficiency?
Perl’s stain ( Amanda’s stain lol)
Fill in the blanks.” The total iron-binding capacity (TIBC) is made up of ____________ &__________.”
Serum iron & unsaturated serum iron-binding capacity (UIBC)
What is the normal range for serum iron?
10–30 μmol/L
What is the normal range for TIBC?
40–75 μmol/L
What is the normal range for serum Ferritin in MALES?
40-340 μg/L
What is the normal range for Serum Ferritin in FEMALES?
14–150 μg/L.
True or False? Hepcidin levels are HIGH in iron deficiency anaemia.
FALSE!! In Iron deficiency anaemia , Hepcidin levels are LOW!!
True or False? There is a Raised Serum Transferrin in Iron deficiency anaemia.
TRUE!!