Anaemia

Question 1

Iron (Fe)

Common indications

Answer 1

1. Treatment of iron-deficiency anaemia
2. Prophylaxis of iron-deficiency anaemia in patients with risk factors such as poor diet, malabsorption, menorrhagia, gastrectomy, haemodialysis and infants with low birth weight

Question 2

Iron (Fe)

MOA

Answer 2

• The aim of Fe therapy is to replenish iron stores.
• Fe is essential for erythropoiesis (the formation of new red blood cells)
• It is required for the synthesis of the haem component of Haem, which gives red blood cells the ability to carry oxygen
• Fe is best absorbed in its ferrous state (Fe²⁺) in the duodenum and jejunum
• Its absorption is increased by stomach acid and dietary acids such as ascorbic acid (vit C)
• Once absorbed into the bloodstream, Fe is bound by transferrin
• Transferrin transports it wither to be used in the bone marrow for erythropoiesis or to be stored as ferritin in the liver, reticuloendothelial system, bone marrow, spleen, and skeletal muscle
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Question 3

Iron (Fe)

Important adverse effects

Answer 3

• The most common adverse effect of oral Fe salts is GI upset, including nausea, epigastric pain, constipation and diarrhoea
• Patients may notice that their bowel motions turn black on treatment
• IV Fe administration can cause injection site irritation and hypersensitivity reactions including anaphylaxis

Question 4

Iron (Fe)

Warnings

Answer 4

• Oral iron therapy may exacerbate bowel symptoms in patients with intestinal disease, including inflammatory bowel disease, diverticular disease and intestinal strictures
• IV iron should be used with caution in people with atopic predisposition due to risk of anaphylaxis reaction

Question 5

Iron (Fe)

Important interactions

Answer 5

• Oral iron salts can reduce the absorption of other drugs including levothyroxine and bisphosphonates
• These medications should, therefore, be taken at least w hours before oral iron

Question 6

Iron (Fe)

Communication

Answer 6

• Explain that treatment should top up their iron stores and improve symptoms of anaemia, but that it may take a few months before the full benefit is felt
• Warn them that Fe may turn their stools black
• Advise them to come back if the iron upsets their stomach, as treatment can be changed to reduce side effects

Question 7

Folic acid

Indications

Answer 7

• Folate-deficient megaloblastic anaemia
• Prevention of neural tube defects
• Prevention of MTX-induced side effects in rheumatic disease, Crohns, psoriasis
• Prophylaxis in chronic haemolytic stats

Question 8

Folic Acid

MOA

Answer 8

• Folic acid is a member of the vitamin B group
• Folic acid is reduced in the body to tetrahydrofolate, which is a coenzyme for various metabolic processes including the synthesis of purine and pyrimidine nucleotides and hence in the synthesis of DNA. It is also involved in the formation and utilisation of formate
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Question 9

Folic acid

Warnings

Answer 9

• Cautioned in
  
  • Pernicious anaemia or other megaloblastic anaemia caused by Vit B12 deficiency

Question 10

Folic acid

Adverse effects

Answer 10

• Abdominal distension
• Appetite decreased
• Flatulence
• Nausea
• Vit B12 deficiency exacerbated

Question 11

Folic acid

Interactions

Answer 11

• Co-administration with AED can reduce plasma concentrations: Phenytoin, Primodine, Barbiturates, Sodium Valproate, CBZ.
• Folic acid will interfere with the toxic and therapeutic effect of MTX
• Trimethoprim + MTX are antifolates; if folate deficiency occurs through prolonged use, folic acid is ineffective. Use folinic acid
• Co-administration of fluorouracil can cause toxicity
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Question 12

Granulocyte-colony stimulating factor (G-CSF)

Indications

Answer 12

• reduction in duration of neutropenia and febrile neutropenia in chemotherapy
• Persistant neutropenia in HIV infections

Question 13

GCSF

MOA

Answer 13

• A glycoprotein which regulates the production and release of functional neutrophils from bone marrow
• Also can cause minor elevations in eosinophils, basophils and monocytes

Question 14

G-CSF

Warnings

Answer 14

• Contraindicated in severe congenital neutropenia who develop leukaemia
• Cautioned in
  
  • malignant myeloid conditions
  • Pre-malignant myeloid conditions
  • Risk of splenomegaly and repute
  • Acute respiratory distress syndrome
  • Oesteoporotic bone disease

Question 15

Filgastim

Adverse effects

Answer 15

• Graft Vs Host Disease (GVHD) has occurred after bone marrow transplantation
• Capillary leak syndrome- rapid fall in BP due to leaky capillaries
• Sweets syndrome- acute febrile dermatosis (fever and sudden onset of rash)
• Pulmonary- ILD, Pulmonary oedema
• Splenomegaly and splenic rupture
• Vasculitis
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