penah dengar pasal hemolytic anaemia???

leiasky

Hemolytic anemia is anemia due to hemolysis, the abnormal breakdown of red blood cells either in the blood vessels (intravascular hemolysis) or elsewhere in the body (extravascular). It has numerous possible causes, ranging from relatively harmless to life-threatening. The general classification of hemolytic anemia is either acquired or inherited. Treatment depends on the cause and nature of the breakdown.

In a healthy person, a red blood cell survives 90 to 120 days (on average) in the circulation, so about 1% of human red blood cells break down each day. The spleen (part of the reticulo-endothelial system) is the main organ which removes old and damaged RBCs from the circulation. In health the break down and removal of RBCs from the circulation is matched by the production of new RBCs in the bone marrow.

When the rate of breakdown increases, the body compensates by producing more RBCs, but if compensation is inadequate clinical problems can appear. Breakdown of RBCs can exceed the rate that the body can make RBCs and so anemia can develop. The breakdown products of hemoglobin will accumulate in the blood causing jaundice and be excreted in the urine causing the urine to become dark brown in colour.

Symptoms
Signs of anemia are generally present (fatigue, later heart failure). Jaundice may be present.
certain aspects of the medical history can suggest a cause for hemolysis (drugs, fava bean or other sensitivity, prosthetic heart valve, or another medical illness)

Classification of hemolytic anaemias
Causes of haemolytic anaemis can be either genetic or acquired.

Genetic
Genetic conditions of RBC membrane
Hereditary spherocytosis
Hereditary elliptocytosis
Genetic conditions of RBC metabolism (enzyme defects)
Glucose-6-phosphate dehydrogenase deficiency (G6PD or favism)
Pyruvate kinase deficiency
Genetic conditions of haemoglobin
Sickle cell anaemia
Thalassaemia

Acquired
Acquired haemolytic anaemia can be further divided into immune and non-immune mediated.

Immune mediated hemolytic anaemia (direct Coombs test is positive)
Autoimmune hemolytic anemia
Warm antibody autoimmune hemolytic anemia
Idiopathic
Systemic lupus erythematosus (SLE)
Evans' syndrome (antiplatelet antibodies and haemolytic antibodies)
Cold antibody autoimmune hemolytic anemia
Idiopathic cold hemagglutinin syndrome
Infectious mononucleosis and mycoplasma ( atypical) pneumonia
Paroxysmal cold hemoglobinuria (rare)
Alloimmune hemolytic anemia
Haemolytic disease of the newborn (HDN)
Rh disease (Rh D)
ABO hemolytic disease of the newborn
Anti-Kell hemolytic disease of the newborn
Rhesus c hemolytic disease of the newborn
Other blood group incompatibility (RhC, Rhe, RhE, Kidd, Duffy, MN, P and others)
Alloimmune hemolytic blood transfusion reactions (ie from a non-compatible blood type)
Drug induced immune mediated hemolytic anaemia
Penicillin (high dose)
Methyldopa

Non-immune mediated haemolytic anaemia (direct Coombs test is negative)

Drugs (i.e., some drugs and other ingested substances lead to haemolysis by direct action on RBCs)
Toxins (e.g., snake venom)
Trauma
Mechanical (heart valves, extensive vascular surgery, microvascular disease)
Microangiopathic hemolytic anemia (a specific subtype with causes such as TTP, HUS, DIC and HELLP syndrome)
Infections
Malaria
Babesiosis
Septicaemia
Membrane disorders
Paroxysmal nocturnal hemoglobinuria (rare acquired clonal disorder of red blood cell surface proteins)
Liver disease

Drug induced hemolysis
Drug induced hemolysis has large clinical relevance. It occurs when drugs actively provoke red cell destruction. Four mechanisms are described below.

Immune
Penicillin in high doses can induce immune mediated hemolysis via the hapten mechanism in which antibodies are targeted against the combination of penicillin in association with red blood cells. Complement is activated by the attached antibody leading to the removal of red blood cells by the spleen.

The drug itself can be targeted by the immune system, e.g. by IgE in a Type I hypersensitivity reaction to penicillin, rarely leading to anaphylaxis.

Non-immune
Non-immune drug induced hemolysis can occur via oxidative mechanisms. This is particularly likely to occur when there is an enzyme deficiency in the antioxidant defence system of the red blood cells. An example is where antimalarial oxidant drugs like primaquine damage red blood cells in Glucose-6-phosphate dehydrogenase deficiency in which the red blood cells are more susceptible to oxidative stress due to reduced NADPH production consequent to the enzyme deficiency.
Some drugs cause RBC (red blood cell) lysis even in normal individuals. These include dapsone and sulfasalazine.

Non-immune drug-induced hemolysis can also arise from drug-induced damage to cell volume control mechanisms; for example drugs can directly or indirectly impair regulatory volume decrease mechanisms, which become activated during hypotonic RBC swelling to return the cell to a normal volume. The consequence of the drugs actions are irreversible cell swelling and lysis (e.g. ouabain at very high doses).

Differential diagnosis
Ineffective hematopoiesis is sometimes misdiagnosed as hemolysis.
Clinically these conditions may share many features of hemolysis
Red cell breakdown occurs before a fully developed red cell is released into the circulation.
Examples: thalassemia, myelodysplastic syndrome
Megaloblastic anemia due to deficiency in vitamin B12 or folic acid.

Therapy
Definitive therapy depends on the cause.

Symptomatic treatment can be given by blood transfusion, if there is marked anaemia.
In severe immune-related hemolytic anemia, steroid therapy is sometimes necessary.
Sometimes splenectomy can be helpful where extravascular heamolysis is predominant (ie most of the red blood cells are being removed by the spleen).


hehehe...kena buat kajian pasal ni...sbb tu saje paste skali kat sni...

fly_in_d_sky

menarik nie
leh explain dlm bahasa biasa tak??

leiasky

nk translate ke bahasa melayu agak susah ar...sbb term dia byk in english....maaf...

azz_azza

penah dengar... nape?

monreyes

nak tanya sikit ttg anaemia....
saya ada masalah iron deficiency
after several blood test dr confirm punca mmg heavy mens...
my specialist presc iron supp masa visit je
bila saya tny samada perlu ambik utk long term dia kata x perlu....
then at times saya akan buat blood test kat normal gp di ofis n my haemoglobin mesti rendah...then dr akan bagi iron supp tapi my gp kata kena ambik long term..
i mmg ada masalah pemknn yg mana mknn yg supply iron naturally mostly sy mmg x mkn.
so..sy nak tny your pendapat..iron supplement ni perlu diambil berterusan..atau masa mens...shj atau mcm mn...
Tq