February 20, 2013

Anaemia is referred to as a condition where the blood level is not enough. Generally, it means the red blood cell content is low. Patients with anaemia will experience lethargy, malaise, reduced effort tolerance and breathlessness. Sometimes it presents with atypical complaints resembling coronary heart disease. I have seen a patient admitted for diagnosis of acute coronary heart disease, found to be severely anaemic and recovers completely after correction of anaemia.

The major cause of anaemia is iron deficiency. Other less common are folate and vitamin B12 deficiency. Haemolytic anaemia occurs when there is increased lysis or destruction of red blood cells. This may occur as a primary disorder or secondary to SLE (systemic lupus erythematosis), drug induced or enzyme disorder like G6PD deficiency. Anaemia may also result from bone marrow infiltration like leukaemia and suppression by drugs like chemotherapy for cancer. Hereditary causes are haemoglobinopathy like thalassaemia and sickle cell anaemia. Very often, anaemia is diagnosed incidentally when patient comes for a medical check-up.

Medical history to be obtained from an anaemic patient are menorrhagia or excessive blood loss during menses, any bleeding haemorrhoids, any passage of black tarry stool indicating blood in stool. History of analgesic abuse is relevant as it can cause erosive gastritis and peptic ulcer. Chronic alcoholics may get folate deficiency anaemia. Clinical examination of an anaemic patient includes a digital examination of the rectum to look for melaenic stool (black tarry).

Preliminary blood tests to be done are full blood count, peripheral blood film, iron studies, blood level of folate and vitamin B12.Once the cause is determined, further test may be needed. It is important not to attribute iron deficiency to dietary insufficiency. Living standard in Malaysia is such that there is hardly any malnourishment except perhaps among the orang asli children who have worm infestation. The main cause of iron deficiency is blood loss like excessive loss in menses, bleeding haemorrhoids and chronic loss from the gastrointestinal tract like peptic ulcer, stomach cancer and colonic cancer. Thus an OGDS (oral gastroduodenoscope) and colonoscopy are warranted. The underlying cause will be dealt with accordingly like surgery for cancer and medication for ulcers.Iron deficiency is easily corrected by oral iron supplements. Blind treatment without determining the cause is unacceptable standard of practice.

Vitamin B12 deficiency occurs when patient develops an antibody which destroys the intrinsic factor which is required for vitamin B12 absorption. This is known as pernicious anaemia. Other causes of vitB12 deficiency are bacterial infection of the intestines where the bacteria utilises all the vitB12 and disease of the terminal ileum (that part of the small bowel where absorption takes place. Treatment of pernicious anaemia is monthly injection of vitB12 for life.

Other rare causes of anaemia need more extensive investigation which may include bone marrow study and is best handled by a haematologist.

Dr. Ng Butt Chin
Consultant Physician