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What is anemia?

Definition of anemia
Anemia is defined as qualitative or quantitative diminution of RBC and / or haemoglobin concentration in relation to standard age and sex and clinically manifested by pallor.
Normally the mucous membrane and nailbed are pink in colour, depending on the amount of Hb in the circulating blood.Clinically, anemia is defined as pallor of the conjunctiva, oral mucosa, tongue, palm and nailbed. Usually pallor appears when the Hb < 10 mg percent, and pale palmar creases are seen when Hb < 8 gm percent.
The best site for examination of pallor of anemia is palmar creases and mucosa of the palate
What is disproportionate pallor ?
Pale complexion is seen in people without anemia also
This is a condition where pallor > anemia this is seen in CRF, hypopitultarism
In males the laboratory criteria for diagnosis of anemia is 
  • Hemoglobin < 13 gm%
  • PCV <42%
  • RBC count < 4.5 million/mm1
In females the laboratory criteria for diagnosis of anemia is
  • Hemoglobin < 12 gm%
  • PCV < 36%
  • RBC count < 4 million/mm3
In children anemia is diagnosed based on the following haemoglobin values
  • 6 months to  6 vears : < 11 gm%
  • 6 years  to 14 years : <12 gm% 
Which are the sites you should examine for pallor?
Pallor is best identified examining the following sites
  • Lower palpebral conjunctiva , retract the patients lower eyelids downward and ask the patient to look upwards — both eyes should be examined at a time.
  • Tongue, specially the tip and the dorsum.
  • Soft palate.
  • Nail-beds you should press the pulp of the finger to see the redness of nail bed.
  • Gums soles and general skin surfaces.
Nail-beds are  known as the windows of the cutaneous capillary network.
What is the clinical classification of anemia ?
The normal haemoglobin concentrations in case of males and females are.
Males — 14.6 to 15.5 g/dl. 
Females — 13.3 to 14.6 g/dl.
14.5 g/dl may be taken as 100%.
Anemia is clinically classified as mild, moderate and severe types. As it is totally a clinical assessment ,it may not correspond with laboratory findings. The colour of the tongue as well as the conjunctiva are more reliable than other sites in adults.In children, palms and soles should be specially looked for.
Mild anaemia — 60-80% of Hb (9-12 g/dl).
Moderate anaemia — 40-60% of Hb (6-9 g/dl)
Severe anaemia — <40% of Hb (<6 g/dl). 
What is the difference between pallor and anemia?
Pallor (paleness) is the waxy appearance of skin and mucous membrane. Pallor  depends on thickness and quality of skin, as well as quality and amount of blood in the capillaries. The terms , pallor and anaemia are not interchangeable. There are many causes of pallor, and anaemia is one of the cause of pallor.  Anaemia is a pathological condition while pallor is a clinical entity.