2. By the end of this session, students are expected to
be able to:
• Describe anaemia
• Discuss classification and clinical features of anaemia
• Outline complications of anaemia
• Explain iron deficiency anaemia
• Explain megaloblastic anaemia
• Describe management of anaemia
3. Overview of Anaemia
• Anaemia: Low haemoglobin concentration in the blood
below reference range for the age and sex of an
individual.Also defined as low blood volume below
reference range for age,sex and physiological condition of
an individual.
• Haem is the oxygen-carrying molecule which contains iron
and it is attached to the proteineous molecule called
globin.
• In practice, anaemia is usually discovered and quantified by
measurement of the RBC count, haemoglobin (Hb)
concentration and haematocrit (Hct).
• Symptoms and signs of anaemia are of paramount
important in diagnosis of anaemia.
4. Reference Range
• Age/Sex Hb conc. (g/dl)
• Cord Blood 13.5-20.5
• 1st day of life 15.0-23.5
• 6 Months– 6 yrs 11.0-14.5
• 6 – 14 yrs 12.0-15.5
• Adult male 13.0-17.0
• Adult female 12.0-15.5
• Pregnant women 11.0-14.0
5. Contributing Factors to Anaemia
• Nutritional factors including diet deficient in iron , folic acid and
vitamin B12 play major roles as aetiology of anaemia.
• Diseases such as sickle cell anaemia, thalassemia, malaria,
hookworm, and chronic infections, are also responsible in causing
anaemia.
• Populations with little meat in the diet have a high incidence of iron
deficiency anaemia because haeme-iron is better absorbed from
food than inorganic iron.
• Certain races and ethnic groups have an increased prevalence of
genetic factors associated with certain anaemia.
Examples are haemoglobinopathies, thalassemia, and G-6-PD
deficiency.
• Overall, anaemia is twice as prevalent in females as in males. This
difference is significantly greater during the childbearing years due
to pregnancies and menses.
6. • The morbidity and mortality of anaemia vary
greatly depending on the aetiology.
• Acute haemorrhage has variable mortality
depending on the site of bleeding (80% with
aortic rupture, 30-50% with bleeding
oesophageal varices, approximately 1% with
benign peptic ulcers
7. Causes of Anaemia
• Increased RBC destruction
o Haemoglobinopathies-SCD and Thalassemias
o Enzyme abnormalities of the glycolytic pathways of glucose metabolism
o Defects of the RBC cytoskeleton
o Fanconi anaemia(membrane disorder)
o Renal failure
o Drugs
o Infections
• Reduced production of RBC
oLack of Iron, Vitamin B-12 and Folate
o BM radiation
o Drug effects eg cytotoxic drug
o Genetic problems eg progenitor sterm cell failure to differentiate
o Infiltrate of BM with malignant cells,sarcoidosis,amyloidosis,TB or Syphlis.
• Blood loss
o Blood loss in( GITtumour in GIT,PUD,Variceal bleeding),trauma,
8. Others are,
• Immunologic - antibody-mediated abnormalities
• Physical effects
o Burns
o Frostbite
o Prosthetic valves and surface
o Hepatic disease
o Collagen vascular diseases
9. • Infections
o Viral - Hepatitis, infectious mononucleosis,
cytomegalovirus
o Bacterial – such as clostridia, gram-negative
sepsis
o Protozoal - malaria, leishmaniasis,
toxoplasmosis
10. Classification and Clinical Features of
Anaemia
Classification of Anaemia
• Anaemia can be classified from three points of
view:
o Pathogenesis
o Clinical presentation
o Red cell morphology
11. • Based on pathogenic mechanisms, anaemia can be divided
into two types.
o Hypo-regenerative: When bone marrow production is
decreased as a result of impaired function, decreased
number of precursor cells, reduced bone marrow
infiltration, or lack of nutrients.
o Regenerative: When bone marrow responds appropriately
to a low erythrocyte mass by increasing production of
erythrocytes.
• Anaemia can also be classified according to the form of
clinical presentation as:
o Acute (usually bleeding or haemolysis)
o Chronic
12. • Morphological classification is based on basic parameters of
red cell morphology such as mean corpuscular volume
(MCV), allows for a quicker diagnostic approach.
o In the morphological approach, anaemia is classified by the
size of red blood cells; this is either done automatically by
machines or on microscopic examination of a peripheral
blood smear.
o The size is reflected in the mean corpuscular volume (MCV)
• Normal size (80–100 fl)- Normocytic anaemia
• Smaller than normal size (under 80 fl)- Microcytic anaemia
• Larger than normal (over 100 fl)- Macrocytic anaemia
14. Clinical Features
• Anaemia goes undetected in many people,
and symptoms can be few and vague.
• The signs and symptoms can be related to
o Anaemia itself
o The underlying cause
15. Symptoms
• Non-specific symptoms of a feeling of weakness, or fatigue, general
malaise and sometimes poor concentration.
• They may report shortness of breath and dyspnoea on exertion.
• In very severe anaemia, the body may compensate for the lack of
oxygen carrying capability of the blood by increasing cardiac output.
The patient may have symptoms related to this
o Palpitations
o Angina (if preexisting heart disease is present)
o Intermittent claudications of the legs (a condition in which cramping
pain in the leg is induced by exercise)
16. o Symptoms of heart failure
o Cough
o Fast breathing/difficult in breathing
o Excessive sweating
17. Physical Signs
• Pallor (pale skin, mucosal linings and nail beds)
• There may be signs of specific causes of anaemia
o Koilonychia (in iron deficiency)
o Jaundice (in haemolysis of red blood cells)
o Bone deformities (in thalassaemia major)
o Leg ulcers (in sickle cell disease)
• In severe anaemia, there may be signs of a
hyperdynamic circulation
o Fast heart rate (tachycardia)
o Flow murmurs
o Cardiac enlargement (cardiomegaly)
18. • There may be signs of heart failure such as
o Oedema
o Tachycardia
o Tachypnoea
o Basal crepitations
o Murmur with or without gallop rhythm
o Cardiomegaly
o Tender hepatomegally
19. • Chronic anaemia may result in behavioural
disturbances in children as a direct result of
impaired neurological development in infants,
and reduced academic performance in
children of school age.
20. Complications of Anaemia
• Anaemia diminishes the capability to perform physical activities.
• This is a result of one's muscles being forced to depend on anaerobic
metabolism.
• The lack of iron associated with anaemia can cause many
complications, including.
o Hypoxemia
o Brittle or rigid fingernails
o Cold intolerance
o Behavioural disturbances in children
• Hypoxemia resulting from anaemia can worsen the cardio-pulmonary
status of patients with pre-existing chronic pulmonary disease. Cold
intolerance occurs in one in five patients with iron deficiency
anaemia, and becomes visible through numbness and tingling
21. • Anaemia in pregnancy may be associated with
increased risk of
o Foetal growth retardation
o Prematurity/premature delivery
o Intrauterine foetal death
o Premature rupture of membranes
22. Overview of Iron Deficiency Anaemia
• Iron deficiency anaemia is the condition in which there
is anaemia with clear evidence of iron deficiency.
Causes
• Gastrointestinal bleeding from ulcers or colon cancer,
heavy and prolonged menstruation in women.
• Chronic diseases, chemotherapy, or renal disease.
• Nutritional causes especially in those with little meat in
the diet. Nutritional causes are rare in non-
menstruating adults and post-menopausal women
23. Clinical Presentation of Iron
Deficiency
• Signs related to iron deficiency depend upon the severity and chronicity of the
anaemia in addition to the usual signs of anaemia.
o Cheilosis (fissures at the corners of the mouth).
o Koilonychia (spooning of the fingernails) is a sign of advanced tissue iron deficiency.
o Pica, the consumption of non-food based items such as dirt, paper, wax, grass, ice
and hair may be a symptom of iron deficiency.
o Restless legs syndrome is more common in those with iron deficiency anaemia.
• Certain clinical conditions carry an increased likelihood of iron deficiency.
o Pregnancy
o Adolescence
o Periods of rapid growth
o An intermittent history of blood loss
• A cardinal rule is that the appearance of iron deficiency in an adult male means
gastrointestinal blood loss until proven otherwise
24. Differential Diagnosis
• Other than iron deficiency, only three conditions
need to be considered in the differential
diagnosis of a hypochromic microcytic anaemia.
o Thalassemias
o Myelodysplastic syndromes
o Chronic inflammatory disease with inadequate
iron supply to the erythroid marrow.
Note that, usually the anaemia of chronic disease
is normocytic and normochromic
25. Overview of Megaloblastic Anaemia
• The most common causes of megaloblastosis are cobalamin (vitamin B-12) and folate (folic acid)
deficiencies
• Predisposing Factors to Cobalamin (vitamin B12) and Folate Deficiency
• Nutritional deficiency (inadequate dietary intake of vitamin B12 and folic acid)
o Dietary folate deficiency also increases in older populations because of poor diets.
o Boiling foods in water dilutes folates, and excessive heating destroys folates.
• Impaired gastric or intestinal absorption of vitamin B12 as in cases of tropical sprue
• Pernicious anaemia caused by atrophic gastritis and parietal cell loss of ability to absorb vitamin B12
is the most common cause of adult vitamin B12 deficiency. It usually occurs in individuals older
than 40 years, and the prevalence increases in older populations.
• Zollinger-ellison syndrome. The large quantity of acid produced leads to gastrointestinal mucosal
ulceration. It also leads to diarrhoea and malabsorption. Malabsorption in ZES usually is
multifactorial, being caused by direct mucosal damage by acid, inactivation of pancreatic enzymes,
and precipitation of bile salts. This may lead vitamin B12 malabsorption.
• Diphyllobothrium latum (i.e, fish tapeworm). This leads to severe vitamin B12 deficiency due to the
parasite absorbing 80% or more of the host’s B12 intake.
• Increased folate consumption- (Folate depletion)
o In contrast to Cobalamin deficiency, folate deficiency develops rapidly because folate stores are
minimal
• Drugs that can cause megaloblastic anaemia are as follows
• Antifolates - Methotrexate, aminopterin, acyclovir
26. Clinical Presentation
• Features are the same as in any case of anaemia however,
specifically a patient lacking folate or vitamin B12 may develop the
following on top of general features of anaemia
o Folate deficiency during pregnancy can lead to neural tube defects
and other development disorders in the foetus. However, folate
supplements during pregnancy have reduced this morbidity.
o Patients with cobalamin and folate deficiency can present primarily
with neurological impairment.
o Neuropsychiatric signs are usually found only in patients with
cobalamin deficiencies.
o Glossitis, characterized by a smooth tongue due to loss of papillae,
occurs in persons with cobalamin deficiency.
27. Management of Anaemia
• Obtaining a history in support of any deficiency should
focus on the patient's diet,evidence of increased
consumption, indications of malabsorption, pregnancy,
any chronic illness and medications.
Laboratory Investigations
• At Dispensary Level
o Hb estimation
o BS for malaria and other parasites
o Urinalysis
o Stool analysis
28. At Hospital Level
Complete blood count
o Hb
o RBC total
o Platelet count
o WBC and differentials
o Reticulocyte count
• Microscopic examination of the peripheral blood smear should be
performed to evaluate the type of anaemia
Others tests include
Serum iron and total iron-binding capacity (TIBC)
Serum ferritin
Evaluation of bone marrow iron stores
29. Treatment of Anaemia
It depends on the severity of the conditions
For severe anaemia - urgent referral with donors
At Dispensary Level
• In cases of repeated attacks of anaemia or if there is no respond to oral medication patient
should be referred to hospital for further investigations and evaluation
• Mild conditions of anaemia can be managed at dispensary level especially if the cause is
known.
o Treat the underlying cause e.g. malaria, hookworms.
o Mild to moderate iron deficiency anaemia is treated by iron supplementation with
Ferrous sulfate or Ferrous gluconate. Vitamin C may aid in the body's ability to
absorb iron.
o Ideally, oral iron preparations should be taken on an empty stomach, since foods may
inhibit iron absorption.
o A dose of 200 to 300 mg of elemental iron per day should result in the absorption of up to 50 mg of
iron per day.
• Gastrointestinal distress is the most prominent complication of oral iron therapy and is seen in 15
to 20% of patients. For these patients, abdominal pain and nausea are the complains
30. • The goal of therapy in individuals with iron deficiency anaemia is
not only to repair the anaemia, but also to provide stores of at least
1/2 to 1 g of iron.
o Sustained treatment for a period of 6 to 12 months after correction
of the anaemia will be necessary to achieve this.
o The response to iron therapy varies, depending upon the
erythropoietin stimulus and the rate of absorption.
o The absence of a response may be due to poor adsorption,
noncompliance (which is common), or a confounding diagnosis.
o If iron deficiency persists, refer patient to hospital as it may be
necessary to switch to parenteral iron therapy or look the cause of
poor response.
o Vitamin supplements given orally (folic acid) or subcutaneously
(Vitamin B-12) will replace specific deficiencies.
31. o Prophylactic folate therapy (1 mg/d) should be
administered during pregnancy and the perinatal
period to meet the increased demand for folate
by the foetus and during lactation.
o Folate should also be given daily to patients with
chronic haemolysis e.g. sickle cell disease.
o Education on diet and the surrounding
environments is important
32. Hospital Level
• It is necessary to find the cause of anaemia and to evaluate its
severity before initiation of treatment
• Once the diagnosis of anaemia and its cause is made, and a
therapeutic approach is charted, there are three major approaches.
o Treating the cause and correcting the anaemia with oral medication
o Treating the cause and correcting the anaemia with parenteral
medication
o Transfusion therapy
• For patients with unusual blood loss or malabsorption, specific
diagnostic tests and appropriate therapy take priority
33. Key Points
• Anaemia is defined as low haemoglobin concentration in the blood below reference
range for the age and sex of an individual.Also defined as low blood volume below
reference range for age,sex and physiological stste of an individual.
• Anaemia diminishes the capability of individuals who are affected to perform
physical
activities.
• Iron deficiency anaemia is the condition in which there is anaemia with clear
evidence of iron deficiency.
• Ideally, oral iron preparations should be taken on an empty stomach, since foods
may inhibit iron absorption.
• The most common causes of megaloblastosis are cobalamin (vitamin B-12) and
folate deficiencies.
• Folate deficiency during pregnancy can lead to neural tube defects and others.
• Dietary folate deficiency also increases in older populations because of poor diets.
• Boiling foods in water dilutes folates, and excessive heating destroys folates.
34. Evaluation
• What are the symptoms of anaemia?
• What are the complications of anaemia?
• What are the signs of iron deficiency anaemia?
• List down signs of vitamin B12 and folate
deficiency anaemia
