Microcytic Anaemia Flashcards
What is the haemoglobin concentration in patients with anemia?
low haemoglobin concentration (<13.0g/dL for men and <11.6g/dL for women)
What are the symptoms of anaemia?
- Fatigue, headaches and faintness
- Breathlessness
- Angina
- Intermittent claudication (referring to impairment in walking, or pain, discomfort, numbness, or tiredness in the legs that occurs during walking or standing and is relieved by rest)
- Palpitations
What are the signs of anaemia?
General
- Pallor
- Tachycardia
- Systolic flow murmur
- Cardiac failure
Specific
- Koilonychia: spoon-shaped nails seen in longstanding iron deficiency anaemia
- Jaundice: found in haemolytic anaemia
- Bone deformities: found in thalassaemia major
- Leg ulcers: occur in association with sickle cell disease.
What are the investigations for anaemia?
Peripheral blood
- Red cell indices: Look at MCHC for AIH, MCHC will increase in AIH as volume has been pinched off but Hb levels the same
- WBC count
- Platelet count
- Reticulocytes
- Blood film
For decreased production
- Reticulocyte Count – to assess production!!
- Thalassemia Screen – via electrophoresis
- Folate / B12
- Iron Studies – the MOST important value you should look at is Ferritin Levels!
For increased loss
- FOB – for BGIT
- Urine Dipstick
- BR, Haptoglobin, LDH (if haemolysis is suspected; raised even if extravascular haemolysis!)
- Direct Coomb’s Test
Examination of the bone marrow is performed to further investigate abnormalities found in the peripheral blood.
What is the relevant history to take in a patient with anemia?
1) Elucidate symptoms of anemia 🡪 palpitations, chest pain, dyspnoea, pallor
2) Duration of Symptoms
If Acute 🡪 more likely to be increased LOSS
- Acute Bleed – Where is it?
- Haemolysis: Elucidate Scleral icterus
- Elucidate dark urine
If Chronic 🡪 more likely to be decreased PRODUCTION
3) Family hx of decreased production – eg: thalassemia
4) Drug history
5) Age
- Women think about menorrhagia
- Men – ulcer (esp if older), colorectal cancer
What are the causes of microcytic, hypochromic anemia (MCV<80)?
- Iron deficiency anemia
- Thalassemia
- Sideroblastic Anaemia
- Sickle Cell Anaemia
- Anemia of Chronic Disease
What are the causes of normochromic, normocytic anaemia?
- Acute Haemorrhage
- Anemia of Chronic Disease
- Renal Failure: hence reduced EPO
- Aplastic Anaemia
- Leukemia
- MDS
- Autoimmune rheumatic disease
What are the causes of macrocytic anemia?
Megaloblastic Anaemia: B12/folate deficiency
Non Megaloblastic Anaemia
- Increased reticulocytes: aemolytic anemia (e.g. Spherocytosis, G6PD, Sickle Cell Anaemia, AIHA, MAHA), haemorrhage
- liver disease
- alcohol
- drug therapy e.g. azathioprine
- Hypothyroid
What are the causes of iron deficiency anaemia?
- *Blood loss
- Blood loss is the MOST COMMON cause of Fe Deficiency!
- Always ask about duration of menses, Hx of Peptic ulcers, NSAID use, melena, blood in stools, haematemesis, hookworm infection!)
Increased demands such as growth and pregnancy
Decreased absorption (post-gastrectomy, Coeliac Disease, antacid use)
Poor intake (ask about dietary intake of red meats & supplementation)
What are the clinical features of iron deficiency?
- Brittle nails
- Spoon-shaped nails (koilonychia)
- Glossitis (we will see atrophy of the papillae of the tongue) 🡪 smooth, redbeefy tongue
- Angular stomatitis
- Brittle hair
- A syndrome of dysphagia and glossitis (Plummer–Vinson Syndrome or Paterson–Brown–Kelly syndrome 🡪 the same)
What are the investigations performed for iron deficiency anemia?
Blood count and blood film
- Microcytic, hypochromic
- There is poikilocytosis (variation in shape) 🡪 hypochromic elliptocytes
- There is anisocytosis (variation in size)
Pale area exceeds 1/3 of diameter.
Serum iron and iron-binding capacity
- Serum iron will fall significantly.
- TIBC rises
- Transferrine rises
Serum ferritin
- Serum ferritin should fall in classical iron deficiency.
OGD and colonoscopy (especially elderly patients): MUST NOT MISS colorectal cancer, diverticulitis / diverticular bleeding and cancer in the stomach.
What is the management of Fe deficiency anemia?
The correct management of iron deficiency is to find and treat the underlying cause, and to give iron to correct the anaemia and replace iron stores.
Best taken BEFORE FOOD – to maximally increase absorption
Recommended daily dose for iron deficiency adults is 150-200mg of elemental Fe. For children, 3mg/kg od/bd
- Ferrous gluconate: 250mg dose but, contains 30mg elemental iron
- Ferrous fumarate: 200mg dose, but contains 66mg elemental iron
Expect improvement (Hb increase >2g/dL after 4 weeks of treatment). Treat for 6 months beyond Hb normalization.
What are the drugs precent absorption of iron?
antacids, quinolones, tetracycline
What are the side effects of iron supplementation. How do you reduce the side effects?
Up to 50% will experience GI side effects e.g. abdominal discomfort, N&V, constipations. Side effects correlated with dose of elemental Fe ingested
Measures to reduce side effects: reduce elemental Fe dosage, start at a small dose, take supplements with meals; can give laxatives for constipation
What history do you need to ask in a patients with thalassemia?
Diagnosis: Who, What, Where, When How?
- Age of diagnosis
- Initial presentation
- Where & How it was diagnosed, how was patient diagnosed, investigations done, f/u status
[Treatment history ]
- Control (therapy, how often):
- -> age at 1st transfusion, age when chelation therapy was started
- -> how many transfusions required a year
- -> any increase in transfusion requirements
- -> Baseline Hb before and after transfusion, any symptomatic anaemia between transfusions
- Compliance
- Complications: transfusion reactions requiring pre- medications, leukocyte filter; anaphylaxis, infection, fluid overload (CCF), haemolysis, TRALI
What are the complications of thalassaemia/ anaemia?
- Symptomatic Anaemia
- Failure to thrive
- Haemolysis, jaundice
- SOB, heart failure from restrictive pericarditis
- Hypersplenism: easy Bruisability (thrombocytopenia); Often ill (leukocytopenia)
- Gallstones from haemolysis
What are the complications of iron overload (haematochromatosis) from chronic hypertransfusion?
Pituitary: Hypopituitarism (Hypothyroidism, Hypocortisolism, Hypogonadism)
- Pubertal Delay (no increase in LH/FSH in puberty)
- Short stature
Hypothyroidism (both Pri & Secondary, from deposition of Fe in thyroid Gland)
Hypoparathyroidism: hypocalcaemia (perioral numbness, paraesthesia)
Cardiomyopathy 🡪 heart failure & arrhythmias
- Sterile pericarditis
- Restrictive Cardiomyopathies 🡪 CCF
- Arrhythmias (both supraventricular and ventricular)
Chronic liver disease (cirrhosis, portal hypertension, splenomegaly)
Pancreas- Diabetes Mellitus: a mixture of T1 & T2
Increased RBC turnover – hyperuricaemia -> gouty arthropathy + jaundice + gallstones
Aplastic crisis from Parvovirus B19 infection – it is a blood-born infection!
What are the complications of chelation (required if ferritin > 1000)?
- Hearing loss (desferrioxamine)
- Vision loss (desferrioxamine)
- Infections (Yersinia, campylobacter)
What is the relevant family history to ask for in a patient with thalassemia ?
- Parent’s genetic status, do they know if they are carriers? Consanguinity?
- Any siblings affected? If so, on treatment?
- Any genetic counselling before?
- Family tree!
How would you perform a physical exam in a patient with thalassemia?
INSPECTION
- Dysmorphism: Thalassaemic facies (frontal bossing, maxillary) hypertrophy
- Growth: not well thrived / Short stature
- Bronzed skin
- Pallor
- Jaundice
- PCT, O2, IV line
ABDOMEN
- Desferal (Deferoxamine) scars (pigmented, round, no lipodystrophy)
- Surgical scars (open/laparoscopy)
- Hepatomegaly + splenomegaly from: Extramedullary Haematopoiesis, Fe Deposition within liver, Liver cirrhosis and Portal HTN
CHEST
- In CCF?
- Apex beat displaced?
- Flow murmur
OTHERS
- Signs of CLD
- Signs of hypothyroidism
- Screen visual acuity
- Tanner staging, if patient allows it.
Thal major vs Thal intermedia VS thal minor patients: transfusion dependence
Thal major patients require regular blood transfusions for severe haemolytic anaemia
- Usually once every 3-4 weeks
- Otherwise becomes very symptomatic
VS Thal intermedia patients who receive transfusions
- ONLY when they are symptomatic or when their Hb level is low
- Symptomatic thal but not requiring transfusion at least during first few years of life
- Patients can survive into second decade of life w/o chronic hypertransfusion therapy
- Subsequently, <6 transfusions per year (usually only needed during illness)
VS Thal minor patients do not require transfusions
Thal major vs Thal intermedia VS thal minor patients: transfusion dependence
Beta-thal major usually presents at 3 to 6 months during the switch from HbF to HbA
Beta-thal intermedia usually presents >18 months of age
Alpha-thal intermedia patients usually present at birth or soon after birth, as alpha chains are needed for both HbF, HbA and HbA2
What are the clinical features of chronic haemolytic anaemia?
- Pallor
- Jaundice (“lemon-yellow” jaundice of unconjugated hyperbilirubinaemia)
- Decreased effort tolerance (from anaemia) – fatigue, postural giddiness, SOB, chest pain, palpitations
- Decreased growth (due to increased caloric requirements of erythropoiesis, and endocrine effects of iron overload)
- Cardiac dilatation and failure if untreated (rarely untreated nowadays)
What are the clinical features of extramedullary haematopoeisis?
Skeletal changes secondary to expansion and invasion of erythroid bone marrow
- Frontal bossing
- Maxillary hypertrophy
- “Hair-on-end” Skulls radiographic appearance of skull bones due to widening of diploic spaces
Hepatomegaly
- Later in life, iron overload results in liver cirrhosis (small and non-palpable)
Splenomegaly
- Splenomegaly may result in hypersplenism – worsens anaemia or causes decrease in other cell lines 🡪 warranting splenectomy
- Look for scar of splenectomy – no palpable spleen
