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Two-year-old boy was rushed to medical facility with complaints of chest and bodily pain.

Any touch of the mother on any part of the body of the child elicited severe pain.

The worried parents said they never had such problem with the first child who is four-years old now. Well, subsequent investigations showed the child to be a sickle cell disease patient (SS) and was experiencing a crisis.

The parents were surprised because they have been married for the past six years and nothing of this nature had been revealed to them. The mother of the child said she went through ante-natal care during pregnancy and was surprised why this was not identified earlier.

The sickling test is part of the battery of tests for expecting mothers at the ante-natal clinic. The sickling test used only up persons with the full sickle cell defect (SS or SC) which is denoted sickling positive. However, if you were an expecting mother carrying the sickle cell trait (AS, AC) the test result will come out as sickling negative.

If you have a spouse who is also carrying the sickle cell trait (AS, AC) then as a couple you have a 25% chance of having a baby who will have sickle cell disease (full defect, that is SS or SC). Let me give a little background to the issues.

Haemoglobin (Hb) is the oxygen carrying protein found in the red blood cells of humans and other mammals. In man it comprises four ‘globin’ (protein) chains, each wrapped around a ‘haem’ (iron containing) molecule.

Newborn babies have a form of haemoglobin, called fetal haemoglobin (HbF), which is largely replaced by adult haemoglobin (HbA) in the first year of life. HbA consists of two alpha globin chains and two beta globin chains. Sickle cell disease (SCD) comprises a group of conditions caused by the ‘sickle’ mutation.

The resulting exchange of valine for glutamine at the 6th position on the beta chain leads to the production of a sickle haemoglobin molecule (HbS) which is of low oxygen affinity and a tendency to clump or clog in the presence of hypoxia (oxygen deprivation). These conditions occur when affected genes are inherited from both parents, that is HbSS.

Under certain circumstances the red blood cells of a HbSS person change their shape from the usual round shape to sickle shape which being not flexible tend to clog the tiny blood vessels causing severe pain at such points in the body (joints, abdomen, lungs, head, male organ, ribs, etc.

The conditions that could lead to sickle cell crisis include fever, fatigue, high altitude, dehydration, prolonged squatting, stress, malaria (and other infections) and cold weather.

Individuals who inherit only one HbS sickle gene from one parent are sickle cell carriers (HbAS), previously known as sickle cell trait. Sickle cell carriers very rarely have clinical symptoms and often do not know they are carrying the HbS gene.

This means that: if both parents have sickle cell trait, their children have: a 1 in 2 chance of having sickle cell trait (or being sickle cell carriers), a 1 in 4 chance of having sickle cell disease (SCD), and a 1 in 4 chance of having no sickle genes.

HbSC is another form of sickle cell disease in which the person has only one copy of the mutation that causes HbS (from the father) and one copy of another abnormal haemoglobin, HbC (from the mother). Other forms are sickle beta-plus-thalassaemia (HbS/âz ) and sickle beta-zero-thalassaemia (HbS/â°). The term disease is applied because the inherited abnormality causes a pathological condition that can lead to severe complications and even death if not promptly managed.

Although SCD occurs predominantly in individuals of African descent, these disorders are also prevalent throughout the Mediterranean; Middle East and parts of India; the Caribbean; and South and Central America.

The common factor to this distribution is a history of malaria, or migration from a malarial area. Within these regions the HbS gene frequency ranges from 10% to 30%. However, due to population migration, SCD is an important part of clinical practice in most countries.

It was therefore gratifying to learn of the plans to draft a National Policy on sickle cell disease in the country. This is being led by the National Newborn Screening Programme for Sickle Cell Disease. This I believe will come out with clear guidelines on the management of sickle cell diseases in the country. This guideline should find space within the standard treatment guidelines of the nation on the management of diseases.

It is important to step up public campaigns on sickle cell disease in the country to dispel the myths and misconceptions associated with it. Public education will enable couples to make informed choices about child birth. I met a rather unfortunate one recently.

The man had two children from a first marriage out of which one was a sickle cell disease (SS) patient. His second marriage has produced two children out of which one is a sickle cell disease (SS) patient.

I asked him why he did not let the spouse go for screening to know her haemoglobin genotype before the marriage (at least drawing from the experiences from the first marriage).

He did not believe he was a contributory factor to the child with the sickle cell disease (SS) from the first marriage. Besides there was not enough time for all the investigations this second time around. Things happened too fast! After thorough counseling the couple became better informed about how to take care of the two SCD children.

Two years ago the Methodist church took up education/awareness on Sickle Cell Disease (SCD) as a national health campaign throughout their churches in the country. This should be taken up by other churches, associations and other interest groups in the country.

Notwithstanding the improvement in health care it is still a challenge caring for a sickle cell disease (SS, SC) person. It is a life-long affair and not many persons can cope with the demands.