Module 4.2.2 (Management of Anaemia) Flashcards
What are the risk factors to be screened for IDA?
- Pregnancy
- Blood loss (GI bleed, menorrhagia, hookworm infestation, medications including NSAIDS, anticoagulant, undiagnosed colorectal, oesophageal or gastric cancer, or inflammatory bowel disease)
- Malabsorption (coeliac disease, gastric surgery)
- Inadequate dietary intake (vegetarian)
- Chronic renal failure on haemodialysis
How to confirm IDA?
Confirm with blood test
What are the FOUR treatment options for IDA
- Dietary advice
- Oral iron supplements (first line)
- IV iron infusion
- Blood transfusion (less common) –> does not restore iron stores in the body
How to correct IDA through dietary modification?
Haem iron (15-35% abs)
- Lean red meat, fish, chicken, organ meats, seafood
Non-haem iron (2-20% abs)
- Lentils, beans, peas, tofu, eggs, iron fortified cereals
Fruit and vegetables (spinach, potato+skin, broccoli, apricots & peaches)
Vitamin C enhances absorption of iron
Phytates (in cereal and legume), polyphenol (in red wine), and tannins (in tea and coffee), calcium rich food and calcium supplements reduces iron absorption
How much oral iron is given? When does maximum absorption occur? What side effects are common?
- 100 -200 mg elemental iron daily
> Preparation available as ferrous salt and iron polymaltose
- Maximum absorption iron occurs when it is given before or between meals
Gastrointestinal side effects are common
- Abdominal pain, N, V, D, constipation, black discolouration of stool
How to manage GI adverse effects of iron supplement?
- Giving iron with or immediately after food
- Use slow release preparation
- Trying different formulation
What drugs decrease iron supplement absorption?
Antacids, H2As, PPIs, calcium
Iron supplements decrease the absorption of?
Iron decrease absorption of thyroid hormones, levodopa, quinolones and tetracyclines antibiotics
What needs to be monitored when on iron supplement?
Monitor Hb (should rise to normal in 2-3 months)
- Continue oral treatment for at least 3 months after the Hb level has returned to normal in order to replenish iron stores
Continue to monitor FBC, ferritin 2 weeks after tx cease and then every 3 months for a year
What type of parenteral iron formulations are there? What are they indicated for?
Parenteral Iron
- Iron sucrose (IV)
- Iron carboxymaltose (IV)
- Iron polymaltose (IV, IM) –> avoid, causes pain and skin straining (IM)
Indicated for
- Severe iron malabsorption
- Non compliance/severe intolerance with oral iron
- Oral iron is inadequate to meet demand
- Excessive iron loss eg renal dialysis patients
- Rapid replacement required
What are the adverse effects of parenteral iron? What to monitor for?
AE
- taste disturbances, N,V, headache, arthralgia, myalgia, tachycardia, BP changes, chest pain, bronchospasm
Monitor for anaphylactic reaction: wheezing, flushing, dyspnoea, dizziness
How to confirm diagnosis of Vitamin B12 deficiency anaemia?
Confirm diagnosis with blood test
- Vitamin B12 level
- MMA specific to vitamin B12 deficiency
- Anti-intrinsic factor antibody (anti-IFAB) – pernicious anaemia
What are the TWO treatment options for B12 deficiency? Which is more potent?
- Cyanocobalamin (oral and IM)
- Hydroxocobalamin (IM) –> more potent than IM cyanocobalamin
What is the initial treatment for the management of B12 deficiency?
IM hydroxocobalamin or cyanocobalamin 1000 mcg on alternate day for 2 weeks or until sign of improvement followed by maintenance tx
What is the maintenance treatment for B12 deficiency? When is IM administration or oral administration preferred?
- Cyanocobalamin 1000 mcg IM once a month
- Hydroxycobalamin 1000 mcg every 3 months (every 2 months if there is sx of neurological deficit)
IM administration preferred to oral if deficiency is due to malabsorption of vitamin B12
Oral administration preferred if deficiency is due to inadequate dietary intake
> cyanocobalamin 50-200 mcg daily in between meals
