Introduction
Today, we are demystifying the so long believed myth that anaemia is a disease. It is not, rather it is a sign of an underlying disease condition. We will discuss general knowledge and information in regards to anaemia before delving to the most common form(or cause) worldwide.
Anaemia by definition refers to reduced haemoglobin concentrations below normal ranges for particular age and sex.
Haemoglobin is the substance in red blood cells that enables these cells to carry oxygen and sometimes, carry some form of carbon dioxide (carbaminohaemoglobin).
It is the amount of haemoglobin in blood that determine if an indivividual will be labelled as anaemic(when they are low) or not(normal or higher than normal).
There are several types of anaemia. The classification is based on morphology , concentration of Hb or cause.
Today, we will classify anaemia based on cell size. Red blood cells, also known as erythrocytes, their volumes (mean corpuscular volume- MCV) or sizes are measured in terms femtolitres/cell. Based on this classification, anaemia is divided into three categories which are microctic hypochromic, normocytic normochromic(or hypochromic) and macrocytic hypochromic.
Microcytic cells is a term referring to cells of smaller than normal sizes(mean corpuscular volume<80 fl/cell). Note that for Africans, <100 fl/cell indicate microcytic hypochromic cells. Several types of microcytic hypochromic anaemia exist. For example- Iron deficiency anaemia (which is the most common form of anaemia worldwide), sideroblastic anaemia and thalassaemia.
Iron deficiency anaemia.
Various parameters are used to diagnose/ rule in iron deficiency anaemia. These include factors such as presence of abnormally small red cells on peripheral blood film, hyphochromatic cells(paler than normal) and lab findings such as low mean corpuscular volume, low mean corpuscular haemoglobin and low mean corpuscular haemoglobin concentration.
Prevalence
The WHO has recognised iron deficiency anaemia (IDA) as the most common nutritional deficiency in the world, with 30% of the population being affected with this condition
Individuals at risk
- Adolescents
- premature newborns
- Pregnant women
- Menstruating females
-These particular groups are at risk of suffering from iron deficiency and hence iron deficiency anaemia as a result of increased demand.
Causes
- Poor absorption from duodenum and jejunum parts of gastroinestinal system due to gastrectomy, enteropathy.
- Diet containing inadequate iron especially for people in institutions- eg old age, prisons
- Rise in demand for iron- in premature babies, pregnancy, during lactation, adolescence and in erythropoietin hormone therapy (for chronic kidney disease)
- Excessive loss of blood in menstruating females as a result of heavy menses
- Loss of blood through gastrointestinal system- due to factors such as bleeding peptic ulcer disease, oral aspirin adminstration and hemorrhoids.
Clinical features
- Symptoms- dietary cravings- pica, easy fatiguability
- Signs;
i. Parlor of mucous membranes/ mucosal surfaces
ii. Painless inflammation of the tongue
iii. Spoon-shaped nails
iv. Angular stomatitis.
Lab findings
- Low red blood cell count
- Increased serum iron
- Low serum ferritin
- Increased tissue iron binding capacity and Transferrin receptor
- Pencil shaped cells
Investigations
- In premenopausal women, we check for any excessive loss of blood through menstruation, frequency of pregnancies and blood clotting disorder von Willebrand disease.
- In children, check for hookworms or poor/ low iron in diet.
- In men and post-menopausal women, loss of blood through GIT is the most common cause for IDA.
Treatment
- Treat the underlying cause
- Administer oral iron supplements eg ferrous sulphate.