Clinical Emergencies Presented by Anemia
Tridip Chatterjee
1,2*
and Annesha Das
2
1
Suraksha Genomics (R & D Division of Suraksha Diagnostics), Kolkata, West Bengal, India
2
Institute of Genetic Medicine and Genomic Science, Kolkata, West Bengal, India
*
Corresponding author: Tridip Chatterjee, Suraksha Genomics (R & D Division of Suraksha Diagnostics), DD-18/1, Sector 1, Salt Lake, Kolkata-700064, West Bengal,
India, Tel: +91-033-6619-1000; +91-09831325280; E-mail: ctridip@gmail.com, tridip.academic@gmail.com
Received date: May 20, 2016; Accepted date: May 28, 2016; Published date: June 04, 2016
Copyright: © 2016 Chatterjee T, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Anaemia affects 24.8% of the population worldwide. It has wide variety in terms of clinical manifestation of the
disease severity. It can also ranges from almost asymptomatic to severe haemolytic anaemia. In contrast to all other
nucleated cells, RBCs show very interesting biology. An alteration in any of the major factors in RBCs (eg. shape,
size, and structural or functional or quantitional abnormalities in haemoglobin) usually results in compensatory
changes in the other compensatory factors. Sometimes, the compensatory responses may fail because of severity
of disease or due to underlying pathologic conditions. The result of failed compensatory responses is cellular
dysfunction, tissue hypoxia and eventual cell death, which ultimately leads to severity in anaemia and emergency
situations due to it.
In this paper, we have concentrated to focus on how the extrinsic and intrinsic defects on RBCs cause severe
haemolytic anaemia, leading to emergencies. We have also discussed the destructions of RBCs in both extra and
intra vascular regions, contributing to severe haemolysis. Other than haemolytic anaemia, other structural and
functional defects of haemoglobin, which can lead to life threatening conditions (e.g.: β thalassemia major and
transfusion dependent haemoglobinopathies) are also being discussed here. In nutshell, this paper is an exclusive
review on all forms of clinical emergencies due to anaemia’s and other haemoglobinopathies.
Keywords: Anaemia; Haemolysis; Haemoglobinopathies
Introduction
Anaemia is defned by an absolute decrease in the number of red
blood cells (RBCs), circulating in the blood. Te diagnosis of anaemia
is based on the laboratory measurements of RBC indices. If that found
to fall below accepted normal values (Table 1) [1], then it is considered
as anaemia.
Age Haemoglobin
(g/dL)
Hematocrit
(%)
Red Blood Cell
Count (x106/mcL)
3 months 10.4-12.2 30-36 3.4-4.0
3-7 years 11.7-13.5 34-40 4.4-5.0
Adult man 14.0-18.0 40-52 4.4-5.9
Adult woman 12.0-16.0 35-47 3.8-5.2
Table 1: Normal values of RBC indices.
In worldwide scale, anaemia afects 24.8% of the population. It is
more prevalent in children and pregnant women [2], than the adult
men and women. It is also seen to be more prevalent in women than
men. Te prevalence of anaemia varies depending on the RBC indices
used to defne it. Anaemias in most cases are chronic, but it can also
give rise to emergency in some special cases or clinical conditions. It
can be presented as an emergency is mainly due to some clinical causes
like acute blood loss or more rarely acute haemolysis or marrow
involvement by hypoplasia or malignancy. More chronic types of
anaemia can also be presented as an emergency, when the
Haemoglobin (Hb) level falls to much lower than the normal level
(Table 1), whereby the patient him or herself develops symptoms or
when other disorders, e.g. myocardial insufciency or respiratory
disease co-exist.
Erythropoesis and Anaemia
Te pluripotent stem cells of bone marrow diferentiate into
erythroid, myeloid, megakaryocytic and lymphoid progenitors.
Erythropoietin stimulates the growth and diferentiation of erythroid
progenitors, resulting in production of RBCs. When the normoblast
extrudes its nucleus, it retains its ribosomal network, which identifes
the reticulocyte. Te reticulocyte keeps its ribosomal network for
approximately four days, three of which are normally spent in the bone
marrow and remaining one in the peripheral circulation. Te RBC
develops as the reticulocyte loses its ribosomal network, and the
mature RBC circulates for 110 to 120 days. Te old erythrocytes are
destined for phagocytosis by macrophages that can detect senescence
signals. Under steady-state conditions, the rate of RBC production is
equal to the rate of RBC destruction, resulting the constant amount of
production of RBCs. Te mass of RBCs remains constant because
equal numbers of reticulocytes replace the destroyed senescent
erythrocytes [3].
Anaemia ofen can stimulate the erythropoiesis, mainly controlled
by the hormone erythropoietin. Erythropoietin is a glycoprotein,
produced primarily in the kidney. It regulates the diferentiation of the
committed erythroid stem cell and thereby controlling the production
of RBCs. Tissue hypoxia and by products of RBC destruction pathway
Emergency Medicine: Open Access
Chatterjee and Das, Emerg Med (Los Angel) 2016,
6:4
DOI: 10.4172/2165-7548.1000327
Review Article Open Access
Emerg Med (Los Angel)
ISSN:2165-7548 EGM, an open access journal
Volume 6 • Issue 4 • 1000327
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ISSN: 2165-7548