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Managing the problem of congential disorders requires the establishment of basic medical genetic services. The World Health Organisation (WHO) has defined the aim of medical genetic services as helping people with a genetic disadvantage (i.e. those affected and those at risk of having a child with a birth defect) to live and reproduce as normally as possible.
Medical genetic services require management programmes for congential disorders. These consist of a comprehensive plan to:
Medical genetic services combine the best possible patient care with the prevention of congential disorders.
Caring for people with a congential disorder involves three steps:
Recognising congential disorders
A congential disorder must be identified as early as possible to ensure the best response from treatment and genetic counselling. In low resource nations, primary health-care providers should learn to recognise congential disorders and diagnose their country’s common and important congential disorders. In South Africa these would include:
A definite diagnosis cannot always be made. However, it remains important to know that the person has a congential disorder and to recognise the disabilities that may be associated with the congential disorder.
Provide appropriate treatment
Having recognised a congential disorder, the primary health-care provider has the responsibility for offering and providing appropriate treatment. This may be available in the local clinic or hospital or may require the patient to be transferred to a regional centre. Whenever possible, treatment should be provided in the primary health-care facility which is closest to the patient and the family’s home.
Offer genetic counselling and psychosocial support
With treatment the affected person and family, especially parents, should be offered genetic counselling and psychosocial support. As far as possible, for common disorders, this should occur at a primary health-care clinic or hospital. Counselling will help them understand and deal with the issues resulting from the birth defect.
Yes. The World Health Organisation, in its discussions on the development of medical genetic services, realised that levels of health care are different between countries, and even within different regions of a country. Therefore, what can be offered to patients in different circumstances varies, but in any situation ‘the best possible patient care’ available should be offered.
In no circumstance should care not be offered.
A birth defect is identified and, where possible, a genetic diagnosis is made in the same way as all medical diagnoses by:
People with three or more dysmorphic features should be assessed for a birth defect.
This is a drawing of family members over at least three generations (a pedigree). It helps to make a genetic diagnosis and identify the method of inheritance of inherited birth defects. The three-generation family tree is drawn after taking a careful family history. Normal individuals, people with birth defects, probable carriers (autosomal recessive or X-linked recessive) and pregnancy losses are all plotted on the family tree. One line is used for each generation.
The following symbols are used in a three-generation family tree:
Parents are linked to each other with a horizontal line (marriage or partnership line), while parents and children are linked with a vertical line (descent line). Two parallel lines link parents who are related (consanguineous).
Figure 2-1: A family tree of a female child with a birth defect, whose carrier parents are unaffected but consanguineous. The affected child’s grandparents and great grandfather are also carriers of the abnormal autosomal recessive gene that caused her disorder.
A genetic diagnosis (or genetic medical diagnosis) is the diagnosis of a disorder which is caused by an abnormal chromosome or gene (a chromosomal or genetic abnormality). Sometimes a genetic diagnosis can be made clinically by recognising a pattern of abnormal clinical signs (a syndrome).
No. In about 40% of people with birth defects a definitive genetic diagnosis cannot be made (e.g. the person has dysmorphic features that do not fit into a recognisable syndrome). They may present with a variety of problems including intellectual, physical, auditory (hearing) and visual (sight) disability and epilepsy. Early recognition of these disabilities is important for treatment and genetic counselling. Care must be given even if a final diagnosis cannot be made.
People with birth defects frequently present with disabilities which can usually be treated and counselled for.
Four means of treatment for people with a birth defect are available. Many treatments cannot cure the problem, but they can improve the quality of life. Unfortunately, many of the latest treatment methods are expensive and not available in low resource countries, including South Africa.
Surgical treatment: Surgery, especially paediatric surgery, often saves lives or offers significant improvement for many serious birth defects. At the primary health-care level, people with conditions that can benefit from surgery need to be recognised early and transferred to the appropriate surgical unit.
Examples include surgery for meningomyelocoele, omphalocoele and heart defects, orthopaedic manipulation and surgery for club foot, removal of congenital cataracts, and surgery for cleft lip and palate. The transfer of the patients with a birth defect, such as an omphalocoele, needs to be carefully managed to ensure that the patient arrives in the best clinical condition possible.
There are two practical approaches for the prevention of birth defects:
These are methods of preventing birth defects by ensuring normal infants are conceived and the embryo and fetus is not damaged by teratogens or constraint during pregnancy (the first eight weeks after conception). These methods need to be in place before conception and are dependent on community education, especially the education of women. These methods are also referred to as ‘primary prevention of birth defects’ and are the preferred method for the prevention of birth defects. All countries should develop their medical services to include these methods of prevention of birth defects, which are mainly carried out in primary health-care centres. They include:
Basic reproductive health approaches are methods aimed at the primary prevention of birth defects.
A functional, accessible family planning service that is well used by people is essential for the prevention of birth defects. If this service is available:
Periconception care is the care of women’s health before conception (i.e. before falling pregnant) and in early pregnancy (the first eight weeks) to prevent birth defects. Periconception care tries to ensure the best possible health care for women to help them conceive a normal infant and to reduce the risks of damage to the embryo in early pregnancy. It should also include fathers in pregnancy preparation and care, and promote responsible fatherhood. The whole community should also be educated about the importance of good periconception care.
Good periconception care can prevent some birth defects.
Improve women’s diet
Birth defects can be caused by deficiencies of certain essential dietary nutrients (e.g. vitamins and minerals). Increasing the quantity of these nutrients in the diet can prevent certain birth defects. The best known example of a birth defect due to inadequate maternal nutrients is fetal brain damage due to the mother’s diet being deficient in iodine. This can be prevented by adding iodine into the populations’ salt supply (fortification). In South Africa table salt is fortified with iodine.
Folic acid is another example. Fortifying a staple food with folic acid, or giving folic acid as a pill (supplementation), for three months before and after conception significantly reduces the birth prevalence of neural tube defects. In South Africa, bread and maize meal are fortified with folic acid. Since starting maize meal fortification with folic acid there has been a 30% reduction in the birth prevalence of neural tube defects.
Diet can also be improved by removing substances that can damage the embryo and fetus (teratogens). The best example is alcohol. Community education to warn women of reproductive age of the dangers of alcohol to the embryo and fetus is necessary.
Improving the diet of women reduces the risk of birth defects.
Avoid and treat maternal infections
All children, especially girls, should be immunised against rubella (German measles) as rubella during early pregnancy causes serious birth defects (congenital rubella syndrome).
Detect and treat maternal health problems
Diabetes mellitus and epilepsy are maternal illnesses that can be detected before pregnancy and correctly treated, reducing the risk of birth defects. Avoid drugs which may damage the embryo or fetus (teratogens) such as warfarin, lithium and some anticonvulsants.
All girls should be immunised against rubella before reaching puberty.
Medical genetic (population) screening uses tests or questions in a population to:
Screening tests are not necessarily diagnostic tests.
When identified by a screening test of being at increased risk, individuals can then be offered further tests, if necessary, to confirm the diagnosis, or treatment to prevent or treat the condition. People being screened, including pregnant mothers, will not have presented with complaints or signs of the disorder for which they are screened.
Medical genetic screening can identify pregnant women at an increased risk of having an infant with a specific birth defect, e.g. Down syndrome or neural tube defect. Couples may be screened for being carriers of a common autosomal recessive disorder and therefore of being at increased risk of conceiving a child with the disorder, e.g. sickle cell anaemia and thalassaemia. For other people it detects an increased risk for themselves being affected by a particular birth defect, e.g. congenital hypothyroidism in infants.
Medical genetic screening is a process undertaken in populations to identify people at increased risk of being affected by, or having a child with, a birth defect.
All medical genetic screening should be carried out with the full knowledge and understanding of the person being screened. There should be pretest and post-test counselling.
Medical genetic screening can be expensive and requires functioning health systems and infrastructure to be done correctly. Each country must decide on its priorities before establishing these screening services. In South Africa the only antepartum medical genetic screening that is offered to most of the population is for Rhesus blood grouping and syphilis. Advanced maternal age screening could and should be offered. Examination of all newborn infants by a trained examiner before discharge from the clinic or hospital should also be easily done.
If a pregnant woman is shown by genetic screening to be at increased risk for having a fetus with a birth defect, she and her partner should receive careful genetic counselling regarding their specific situation and the options available to them.
This counselling will offer them two choices:
To have prenatal diagnosis: Prenatal pregnancy diagnosis can confirm whether the fetus does or does not have a particular birth defect. This may require invasive procedures such as amniocentesis to obtain fetal cells or amniotic fluid for testing. Amniocentesis involves inserting a thin needle under ultrasound guidance through the abdominal wall into the uterus. There is a small risk that the procedure will cause complications, including a miscarriage. This risk is about 1% with an experienced operator (sonographer). Woman should be informed of this risk so they can include this information in their decision on whether or not to have an amniocentesis.
Ultrasound examination can also be used to make a prenatal diagnosis. An ultrasound examination is a non-invasive procedure that can be very helpful in identifying structural abnormalities.
To continue the pregnancy without prenatal diagnosis: A pregnant woman may decide to take this choice, knowing and understanding the risks of having an infant with a birth defect.
Figure 2-2: Amniocentesis to obtain a sample of amniotic fluid.
Once a pregnant woman, preferably together with her partner, has received careful genetic counselling regarding her specific situation, she should consider the options available to her. It is particularly important that she is given detailed information about the severity of the disability and the mortality risk associated with the specific birth defect. The health-care facilities available to manage an infant born with that particular birth defect must also be known. Only then, can she make a choice of whether to continue with the pregnancy.
Counselling is a process of education, communication and support by which a counsellor helps a person or people to cope with difficult situations in their lives so that they are able to make important decisions and find realistic ways to solve their problems. Counselling, therefore, helps people to make their own informed decisions and supports their choices, rather than simply telling them what to do.
A counsellor is someone who is trained to educate, assist and give psychosocial support to people with problems. They offer relevant information and discuss options for people to manage their problems and better cope with their lives. This empowers peoples to make their own decisions and take the best course of action according to their personal circumstances, customs, and religious and moral beliefs.
Counselling is about empowering people to make their own informed decisions and to cope with or solve their own problems.
Two essential skills are needed for counselling:
Communication in counselling is a two-way process in which information, knowledge, thoughts and ideas are passed between the people being counselled and the counsellor. The spoken word is the most important means of communication.
However, the counsellor must be aware that people may also pass important messages by showing their emotions and in their body language (how they act). The counsellor must learn to pick up these signs as it helps in gathering information and giving appropriate understanding (empathy) and emotional support.
Effective communication requires the skill of active listening.
Effective communication is a combination of active listening and using words with care and consideration.
Active listening is the process of hearing not only the words people say, but also noting their body language and emotional reactions, and trying to understand the meaning behind their words and actions. In order to understand what a person is saying and to respond appropriately, the counsellor must become skilled in actively listening to people.
A good listener should:
Active listening is the key to effective counselling.
‘Words are like medication, they have the ability to heal but their side effects can be harmful.’
‘If you do not listen to the person being counselled, do not expect them to listen to you.’
Genetic counselling is an educational process which helps people with a birth defect, or a risk of giving birth to a child with a birth defect, and their families to understand:
Genetic counselling helps people and their families who are:
Genetic counselling assists these people to make their own informed decisions and choices. It also helps them take charge and accept responsibility for coping with and solving situations in their lives that occur because of a birth defect.
Genetic counselling helps individuals or families who have a birth defect, or are at risk of giving birth to a child with a birth defect, to understand, manage and come to terms with the situation.
The main steps in genetic counselling can be remembered by using the word DIAS (i.e. an anagram). DIAS stands for:
Define the problem:
Confirm a diagnosis, if possible, and identify those issues, related to the diagnosis, concerning the counselled person or persons. Find out from the person or people being counselled what they expect and need from the genetic counselling.
Inform fully (educate) the person or the people being counselled about the diagnosis, the cause, the clinical features and the prognosis, the available treatment, genetic risks (risk assessment) and the options for risk reduction or prevention in future pregnancies and family members.
Allow people to make their own decisions:
With the information available to them, the individuals or family should be encouraged to make their own decisions regarding their situation based on to their personal circumstances, customs, religious and moral beliefs (autonomous decision making). These decisions must be accepted and respected by the genetic counsellor, nursing staff and medical team involved in their care.
During the genetic counselling process, and thereafter, individuals and family should receive the understanding (empathy), psychological (emotional) and social support they may need or request to enable them to make the necessary decisions and to adjust to their particular circumstances. This may require referring them to other professionals and social agencies.
Note that there are enormous differences between genetic counselling and simply providing information and advice.
A number of different social grants are available for individuals with birth defects in South Africa (as listed in Addendum B).
A good genetic counsellor should:
A doctor, genetic-trained nurse or genetic counsellor, provided they are competent and have received appropriate training.
Nursing staff, with appropriate training, have been found to be competent at providing genetic counselling in under-served areas in South Africa. Unfortunately, due to the lack of trained and experienced staff, people needing genetic counselling are often counselled by untrained or poorly trained people.
Any person who is affected by a congential disorder, or at risk of inheriting a congential disorder, or at risk of passing on a congential disorder to their children.
Any person who is affected by a congential disorder, at risk of inheriting a congential disorder, or at risk of giving birth to a child with a congential disorder should be offered genetic counselling.
When a woman is pregnant her wish and expectation are for the birth of a normal child. Giving a woman and her partner news about a congential disorder causes them great distress. They will have to face loss, including loss of life, health or the possibility of not having a normal child.
People who are faced with loss tend to respond in a manner which can be predicted. Counsellors breaking bad news should be aware of this so that they can assist people through the process.
People who suffer loss may go through a typical series of reactions. These are:
When faced with bad news involving loss, many people first refuse to believe what they have been told. This is their way of giving themselves time to begin to deal with and understand the terrible news that causes them to feel hopeless and helpless.
Once they realise the news is true; the next reaction may be anger, rage or resentment. This is often directed at other people including family members (e.g. wife or husband, father or mother), friends, medical or nursing staff and even God. It is a defence that people use to protect themselves against despair, and a genetic counsellor must understand this and support the person being counselled through this stage.
In this stage, which is usually short, people may try to enter into some sort of bargain with God, to try and reverse or put off feeling the loss.
Eventually, after a person has denied, raged and bargained they begin to realise the great loss they have suffered and this may result in depression. They need to receive acceptance, understanding and empathy, and be given space to freely express their feelings to help them through this period.
Eventually the loss is accepted and the person begins to adjust to the changes the loss has brought to their life. At first there is a feeling of numbness which becomes a very sad period. Although this sadness will be overcome and the person will continue with their life, at times in the future they will be reminded of their loss, resulting in sadness or anger once again.
Before reaching acceptance, some people may move forward and backward through the above stages while others may only go through some of the stages.
The normal response to loss is a sequence of denial, anger, bargaining, depression and acceptance.
Yes. Some people have an abnormal grieving (mourning) reaction. They may take too long or not be able to pass from one stage to another, or have an abnormally strong reaction in a particular stage. Thus a person may become stuck in denial and be unable to come to terms with the bad news, have excessive anger, which can damage their relationships with family and friends, or cause them to blame caregivers, or become pathologically depressed.
The genetic counsellor needs to be aware that abnormal grieving reactions can develop, be able to recognise them as early as possible, and refer the person for expert management.
Genetic counsellors have to use their ability in effective communication to break bad news. Preparing for and breaking bad news is very important because the way this is done may greatly affect the response of the person receiving the news. The counsellor should therefore follow guidelines to try and ensure that this is done in the best possible manner. This should include:
End the counselling session with an open invitation to those being counselled to contact the genetic counsellor with any further queries, need for psychosocial support or for further genetic counselling they require. Provide them with contact particulars.
A woman who is one month pregnant, and has a three-year-old child with a congential disorder, visits her family doctor and asks if anything can be done to find out whether her fetus has the same congential disorder. After taking a careful family history, the doctor draws a three-generation family tree.
The risk of having a child with congential disorders can sometimes be reduced with basic reproductive health approaches, such as family planning (deciding not to conceive) and periconception care.
This is the care of women before conception and during the first eight weeks of pregnancy, which may reduce the risk of congential disorders. It aims for optimal health care for women before conception and in early pregnancy to increase the chance of a normal infant.
Essential substances, such as folic acid and iodine, can be added to food in the diet (fortification) or can be taken separately as a pill, tablet or capsule (supplementation). Folic acid and iodine are often provided as either fortification or supplementation.
This is a drawing (a pedigree) of three generations of that family showing normal individuals and those who have a birth defect or are carriers of a congential disorder.
It helps to identify patterns of inheritance of a birth defect, e.g. autosomal dominant, autosomal recessive or X-linked recessive. This makes it easier to predict whether a congential disorder is likely to occur in a given pregnancy.
Parents who plan a family are concerned about the possibility of having a child with congential disorders. They speak to friends and say they have heard about medical genetic screening for congential disorders but do not know what the term means.
Medical genetic screening, or population screening, is a system that uses questions or tests in a community to identify individuals at increased risk of having a congential disorder or a woman having a child with a congential disorder.
They can be offered further tests to confirm whether or not they, or their fetus, have the congential disorder or are likely to pass the problem on to their children.
No. This is why they need to be identified by a screening method.
Prevention or treatment can be offered to these people. For example, they may decide not to have children if there is a high chance that their children may be affected by a serious genetic defect, such as cystic fibrosis. On the other hand, the infant could be offered treatment for a condition, such as haemophilia, before it presents with serious complications.
A nurse wants to train as a genetic counsellor. She speaks to the tutor of a genetic counselling course to find out more about counselling. She also reads a book about caring for parents of children with birth defects.
It is a process of education, communication and support which helps people with a birth defect or who are at risk of giving birth to a child with a birth defect. It enables them to understand the diagnosis, cause, method of inheritance, clinical effects, prognosis and treatment and risk of recurrence of the birth defect.
The main goals of a genetic counsellor are:
During counselling, people are educated about their problems, receive options for managing the situation and are empowered to try and understand their problem and then make the best informed decision for themselves. They are helped to come to terms with their situation and solve the problems that occur.
They should be able to communicate well with people. Active listening is particularly important.
It is the ability to hear not only the words people say but also note and interpret their body language and emotional reactions. This helps to understand the meaning behind their words.