RELEVANCE OF BLOOD INVESTIGATION ………prevent or prepare for it.

INTRODUCTION

Blood is a very vital part of the circulatory system. It is usually red in colour as seen when we have a cut or injury. A proper look at its picture and contents gives a lot of information on various forms of health conditions that can be diagnosed through screening of the blood.

It was observed that while data were collected from personnel, when it got to the area of feeding in information for blood group and genotype many were not forth coming.

Some claimed they have never done it, though it was requested as part of needed information.

Others claimed to have forgotten which ought not to be so.

While a group  gave information that was not theirs, this is dangerous.

Then some that know theirs did not know its relevance.

The aim of the write up is to create awareness on the need for some blood investigations, their relevance as well as correcting misconceptions.

That red substance (blood) is made up of cells which include:

- Red blood cells (RBC) that carries oxygen.

- White blood cells (WBC) that help to fight infections.

-Platelets that help in controlling bleeding.

-The plasma which is the fluid that contains proteins and other elements.

The information that is not in the cell are found in the plasma or serum (i.e. plasma without proteins).

Therefore it is worth noting that parameters in the blood if too high or too low are markers to various forms of health conditions and their progress.

Some Blood Investigation

a.       Pcv (packed cell volume) for anaemia if low or polycythaemia if high.
(Range Males:42- 52%; Females:  37- 47%)

b.      Malaria parasite for diagnosis of malaria.

c.       Widal test for typhoid.

d.      Retroviral screening for HIV

e.       Pregnancy test

f.       Blood group

g.      Genotype

h.      Random or Fasting blood sugar for Diabetes, hypoglycaemia

i.        Renal (kidney) functions

j.        Infections  e.g. Syphilis, Hepatitis,

k.       Others such as Haemophiliacs, cholesterol level etc   

Why do blood investigation

a.       To aid in making diagnosis.

b.      To monitor progress of disease i.e. for follow-up.

c.       To know treatments patients can withstand

d.      To give a better idea during counseling of patients.

For the purpose of this lecture we will focus on the following:

-          Blood Group in blood transfusion, heamolytic disease of newborn.

-          Genotype in sickle disease

-          Retroviral screening in early treatment or continuous negativity.

-          Others e.g. Kidney disease,  Diabetes mellitus etc

BLOOD GROUP (ABO and Rhesus Factor): The red blood cells contain certain substance called antigen on the surface which differentiates one person from the other. There are 4 major blood groups:

-          A      have the A antigen

-          AB   have both A & B antigens

-          B      have the B antigen

-          O     has no antigen on its surface.

Rhesus factor: These blood groups can either be positive or negative depending on the presence or absence of another antigen called the Rhesus factor.
v  Present in Rhesus positive   e.g. A rhesus positive
v  Absent in Rhesus negative. e.g. B rhesus negative

BLOOD TRANSFUSION: This is giving of blood to some body who has lost blood either during operation, after an accident or blood level is reduced due to an on going disease condition. The transfused blood can be from a donor or same person. One of relevance of blood group is during blood transfusion.

The O negative blood is the actual universal donor i.e. can donate to the other groups but cannot receive.

The AB positive group is the universal recipient who can receive blood from any of the above groups.

Transfusion of blood group that is not compatible can be fatal before any intervention can be made. This has become important especially during emergency in case of an accident knowing your blood group can save a lot of time and you can save a life or your life can be saved by merely knowing your blood group . When a person carries a wrong blood group about, he or she might not be lucky enough on the day of emergency. Suppose the attending medical personnel are not patient enough to check his/her blood and decides to work with the one they have due to the severity. The wrong blood might go in before they realize it. 

For example, I was one day asked by a colleague on the corridor of the hospital what was my blood group as soon as I mentioned it. He was very glad that I share the same blood group with the wife who was at that time loosing blood after a caesarean section. What she needed was to be transfused with fresh whole blood and I gladly went to donate to save her life.

HEAMOLYTIC DISEASE OF NEWBORN: A reaction that occurs which destroys the red blood cells of a child delivered by a sensitized Rhesus negative mother with the consequence of either the child dying, having the brain affected or if quick intervention is made will need exchange blood transfusion. Another relevance of the blood group is when a woman with the Rhesus negative blood is pregnant for a man who is Rhesus positive. If this is not taken into consideration for appropriate intervention to be taken. The woman who is sensitized after her first delivery as there is contact between the fetal and maternal blood. Antibodies are now developed against the rhesus positive blood, any positive blood that comes in contact with the mother’s blood is immediately agglutinated and destroyed. In some cases if the first child is lucky enough to scale through, subsequent children suffer severe anaemia called heamolytic disease of the new born which can be fatal. For those that survive, after severe destruction of RBC release of haemoglobin causes severe jaundice (yellow colouration of the skin and eyes). This released haemoglobin because the baby can not handle it crosses into the brain destroying its tissues a condition called Kenicterus. These children either die or become mentally retarded if quick intervention is not done usually exchange blood transfusion depending on the severity. This explains some cases where after the first child other children either die in the womb or at birth or after a few days hence they are called “Ogbanje”. 

The advent of Anti D, a drug that is given to negative mothers within 24- 72 hours after birth has reduce this incidence of Ogbanje especially in Urban area  where newly delivered mothers get access to this drug. This drug actually prevents the formation of antibodies against positive blood. So if a person does not know her blood group, the necessary precautions cannot be taken incase she is negative married to a positive man. This will save the stress of thinking one child is Ogbanje and the energy and time spent on praying against it can be channeled to other things. There was a woman who Rhesus negative, never took it serious. After delivery was made to stay in the hospital but she refused. After much trouble despite the advice she insisted on going with the baby only for her to come back the next day with a deeply yellow baby. All efforts to save the baby were waste of time before the baby died.

HEAMOGLOBINOPATHIES: Haemoglobin (Hb) is the oxygen carrying pigment in red blood cells of vertebrates. The inherited disorders of haemoglobin in humans are termed haemoglobinopathies.

- Normal haemoglobin is the Hb A,

- Abnormal   haemoglobin include

 Hb C, Hb E, Hb I, Hb J, Hb S etc.

For the purpose of this talk we will be dealing with the Hb A and Hb S combinations then the Hb C.

The major combinations are in the form of

Hb AA = Normal genotype

Hb AS = Carrier (no manifestation)

Hb SS and SC = Sickler (recurrent crisis, anaemia)

This is what referred to popularly as Genotype.

Intending couple ought to know their heamoglobin genotype so they can have an idea of the genotypic make-up of their children.

A major problem originating from this is giving birth to a child with Sickle Cell trait (SS or SC) i.e. the child has inherited the Hb S from both parents giving him or her the Hb SS trait, this result in severe heamolytic anaemia (i.e. destruction of RBC) called sickle cell anaemia.

Sickle cell anemia is a particularly a severe disease in that not only is it a hemolytic anemia, but also a vaso-occlusive condition. The clinical findings can then be divided into one of these two groups:

a. Effects of chronic hemolysis

Anemia pretty much self-explanatory

Jaundice,due to rapid heme turnover and subsequent generation of bilirubin

Cholelithiasis. It has been classically taught that sickle cell patients are prone to the formation of calcium bilirubinate gallstones due to excess bilirubin secretion into the hepatobiliary tree.

Aplastic crisis. Many of us have brief episodes of marrow aplasia as a result of common viral infections. With a normal erythrocyte life span of 120 days, no anemia results from an unnoticed marrow shut-down of a few days. However, the sickle cell patients, with their markedly abbreviated rbc life span, can have a precipitous fall in hematocrit (and retic count) under such conditions. This may be life-threatening.

Hemolytic crisis. Most sickle cell patients establish a stable, tonic level of hemolysis. Rarely, for obscure reasons, they experience a catastrophic fall in hematocrit, increasing intensity of jaundice, and increasing reticulocyte count. This is called a "hemolytic crisis."

b. Effects of vaso-occlusion

Dactylitis. Resulting presumably from infarction or ischemia of the bones of the hands and feet, this is often the presenting manifestation of sickle cell disease in a six-months-old infant. The hands and feet are swollen and painful.

Autosplenectomy. In childhood, the spleen is enlarged due to excess activity in destruction of the sickled erythrocytes. Gradually, the spleen infarcts itself down to a fibrous nubbin.

Priapism. This refers to a painful and sustained penile erection, apparently due to sludging of sickled cells in the corpora cavernosa. Sometimes the penis has to be surgically decompressed. Repeated episodes of priapism cause the spongy erectile tissues to be replaced by fibrous tissue, with impotence being the end result.

Renal papillary necrosis. The physiologic function of the loops of Henle makes the renal medulla an eldritch, unbodylike area of high hematocrit, high osmolarity, low pH, hemodynamic stasis, and low P_O2. All of these conditions predispose to sickling and infarctive loss of the papillae of the pyramids. The result is inability to concentrate and dilute urine. Even sickle cell trait individuals may experience episodes of haematuria, presumably due to this mechanism.

Infarctive (painful) crisis. Increased sickling activity may be brought about by any general stress on the body, especially infection. Almost any organ may suffer acute infarction (including the heart), and pain is the chief symptom.

Sequestration crisis. This occurs mostly in infants and young children and is characterized by sudden pooling of sickled erythrocytes in the RES and vascular compartment. This produces a sudden fall in hematocrit. Sequestration crisis may be the most common cause of death in sickle cell patients in the youngest age group.

Leg ulcers. After all of the disasters mentioned above, this seems trivial. However, the deep, nonhealing ulcers of skin and tela subcutanea (classically around the medial malleolus) may be the only clinical manifestation of sickle cell disease in an otherwise well-compensated patient. These may be the only bugaboo standing between the patient and a productive, financially solvent life.

When the child is passing through this recurrent painful crisis and with the fear of impending death anytime, he/she curse the day he/she was brought into this world. They also the parents that brought them to suffer this pain, they are usually not happy when they realize that this could have been prevented.

To make the situation worse, the future of the child is not guaranteed as the parents live in constant fear.

In some cases the couples are not aware of their genotype while some are aware but tend to ignore it without considering the gravity of it.

If this issue of genotype is really put into consideration sickle cell traits would gradually be eradicated. Hence intending couples need to know their genotype, this is not the issue of love, family ties or parental influence because when the crisis begin all these are forgotten the couple are filled with regrets but they can not really do much about it. They spend most of their income taking care of these children; imagine if the income is not there, better still the income could have been used to do better things for a child without this disease. Intending couples need to consider these properly for them to prevent it or prepare for it.

 Combinations and chances for each pregnancy:

If Hb AA marries Hb AA all offspring are Hb AA

If Hb AA marries Hb AS chances:     50% Hb AA

                                                             50% Hb AS

If Hb AS marries Hb AS chances:       25% Hb AA;

                                                              50% Hb AS;

                                                               25% Hb SS.  

If Hb AA marries Hb SS all offspring are      Hb AS

If Hb AS marries Hb SS chances:           50% Hb AS

                                                                50%  Hb SS.

It is important to note here that in cases where the chances are either 50 or 25 % does not mean for every number of children that they will manifest.

E.g. Hb AS + Hb AS =   25% Hb AA,

                                         25% Hb SS,

                                         50% Hb AS.

 In this case the Hb AA, Hb SS or Hb AS combination can be present in all the offspring. It has nothing to do the number of children, this is where the issue of luck comes but how lucky can one be as they don’t take turn to come.

Knowing the risk involved and going ahead is gambling with the health of the unborn child hence proper thought need to be given to prepare for or prevent it.  

RETROVIRAL SCREENING: This is the screening for HIV infection. Another area where screening for it is necessary. This is important to us all as we have at one time or the other exposed been various risks in the past with respect to:

Unscreened blood contact especially during crisis

Surgical operations

Sharing of sharp piercing objects e.g. blades, clipper, needles etc

Unprotected sexual intercourse

Taking injection from road side patent medicine dealers

Taking immunization etc

These factors stated above could have one time been experienced putting a person at risk.

Remembering that the time take for manifestation to become obvious is not specific, it varies from person to person. Screening for HIV contrary to what most people believe leaves a person between two options:

- Positive

- Negative.

v  A positive person who is aware from the onset learns how to remain healthy, seek proper medical attention unlike those that will wait till HIV has progressed to AIDS where in some cases little or nothing could be done.

v  Then for those that are negative who now strive to remain negative.

  

      OTHER HEALTH CONDITIONS

Ø  KIDNEY DISEASE:   

Serum Electrolyte, Urea and Creatine can be used to monitor the progress renal failure as well as when to carry out some intervention e.g. haemodialysis.

Ø  DIABETES MELLITUS:

The level of blood sugar can be used to make a diagnosis of diabetes mellitus. The progress to access the degree of control is done by monitoring Random and the Fasting blood sugar.

Ø  OTHERS:

1.    Checking for malaria parasites in case of malaria attack.

2.   Monitoring serum bilirubin level in infant with jaundice to know when to carry out an exchange blood to prevent brain damage.

3.    In liver disease some elements in the blood can be used to the level of damage that has been done.

4.    The popular Typhoid is also diagnosed using the blood.

FACTORS THAT MAKE PEOPLE REFUSE BLOOD INVESTIGATION

1.      Ignorance: Some people are ignorant of what the result would be used for. The fact is that a Physician is not a magician he needs to tie clinical findings with results of investigations carried out to make appropriate diagnosis then ideal treatment offered. Remember the result of the investigation gives a picture of what is on the inside. This is what the Physician is trained to interpret and do something about.

2.      Financial implication: while some people think it is too expensive to carry out investigation, they tend to seek places where little or no investigation is done but treatment is offered. On the long run, they spend more money.

3.      Time: Another group think that it is time wasting to carry out these investigations. It is important that appropriate investigation be carried out for a once and for all treatment. Some people like to receive blind treatment because of time, unknown to them when complication sets ii or the case become advanced more time will obviously be spent.

4.      Misinformation:  This is a situation where some people especially traditional healers tell a person that a particular medicine can cure a variety of ailment. That patient will obviously not want to be investigated since the cure is more important, but most of them fail either leading to death or worse complication. Many people especially accident victims who have had fractures suffered from this condition where they undergo surgery after some years with shortening of limb or have their cut off.    

CONCLUSION

To the man it will just be pain of maybe his money was wasted but the woman when there is nothing to show for the stress of carrying the pregnancy for nine months with the entire attendant trouble that goes with pregnancy.

A couple ought to be satisfied when they see their healthy child growing up not spending most of their time in the hospital. So it’s a plan to be executed by the two not one person. From the above, it is now obvious that the need for these blood investigations can not be over emphasized. It is both time and life saving. It will also prevent us from some embarrassing life situation like giving birth to children with sickle cell disease, bilirubin encephalopathy leading mental retardation and other situation. Situation that can be prevented need to be done now while as for those that have passed the stage of prevention can then be prepare for it. For those that are already married with out these investigations some things can still be done to avert some other thing and they can use it to advice their children.

Finally, for those that are yet to get married much still need to be done. Investigate your selves, take a painful decision now if need be to avoid future regrets. And on the other hand make up your mind to face the music which I know it’s not going to be easy.

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