Alzheimer’s disease

Alzheimer’s disease (AD) is a disorder that causes degeneration of the cells in the brain; and it is the major cause of dementia, and is characterized by a decline in thinking ability and independence in personal daily activities. It also causes the brain shrinkage and death. Alzheimer’s disease affects people of age 65 years and above with only 10% of cases occurring in people younger than this.

In AD, plaques are formed in the hippocampus, which helps in encoding memories, and in other areas of the cerebral cortex that are involved in thinking and making decisions.


Symptoms of Alzheimer’s disease

Alzheimer’s disease develops in a progressive manner, with the symptoms becoming worse over time. The key features of AD are memory loss, and it is also the first symptoms to develop.

Symptoms of Alzheimer’s disease include:

Memory loss: An AD patient usually has difficulty in taking and processing new information as well as in remembering new information. This leads to:

  • Repeating questions and conversations.
  • Forgetting about events or appointments.
  • They wander about and usually get lost.

Cognitive deficit: The patient experiences difficulty in reasoning, complex task and in judgment.

Problem with recognition: The patient may not be able to recognize faces or objects.

Problems with speaking, reading and writing: The patient would develop difficulties remembering common words, or make more speech, writing and spelling errors.

Personality and behavior changes: The patient may experience certain changes in personality and behavior that include:

  • A loss of interest of motivation in activities they previously enjoyed engaging in.
  • A loss of empathy.
  • The person may become upset, angry or worried often than before.


Stages of Alzheimer’s disease

Alzheimer’s disease occurs in stages; from mild to severe cases.


Mild Alzheimer’s disease

Patients with mild AD have memory problems and cognitive difficulties, which may also include:

  • Difficulties in handling money or paying bills.
  • Wandering aimlessly and getting lost often.
  • Experiencing behavioral and personality changes.
  • Not being able to perform daily task in shorter time.


Moderate AD

In this stage of the disease, the parts of the brain responsible for language, senses, reasoning and consciousness are damaged. The patient finds it difficult recognizing family and friends, lose the ability to learn new things and finds it difficult coping with new the situation. Hallucinations, delusions and paranoid sets in.


Severe AD

In this stage, plaques and tangle, which cause brain tissue to shrink substantially, begin to occur.


Risk Factors of Alzheimer’s Disease


The older a person becomes, the greater the person’s chances of developing Alzheimer’s disease. Age remains the greatest risk factor of Alzheimer’s disease.

Family history: An individual, whose parents or sibling has the disease, is at a higher risk of developing the disease.

Down syndrome

Many people with Down syndrome develop Alzheimer’s disease later on. This may be associated with having three copies of chromosome 21 and subsequently three copies of the gene for coding the protein that leads to the formation of beta-amyloid. Patients of Down syndrome expresses signs and symptoms of AD 10 to 20 years earlier than in general population.

Head Trauma

Patients who suffer traumatic brain injury (TBI) are at greater risk of developing AD. The more severe the TBI, the greater the chances of developing AD.


Treatments of Alzheimer’s disease

Alzheimer’s disease has no cure, currently. But there are however, some available medicines that can temporarily reduce the symptoms. Some of the medications for AD are:

Acetylcholinesterase (AChE) inhibitors

The medicine works by increasing the cellular levels of acetylcholine. Acetylcholine is a brain neurotransmitter that helps nerve cells communicate with each other.

AChE inhibitors include Donepezil, Galantamine and Rivastigmine. They can be prescribed for people with early-to mild-stage AD.

Some side effects associated with these medications include nausea, vomiting and loss of appetite.


Memantine works by inhibiting the effects of excess amount of glutamate. It is best used to treat moderate or severe AD and good for those who cannot use AChE inhibitors.

Side effects associated with memantine medication include headache, constipation and dizziness.



Sickle cell disease

Sickle cell disease is an inherited blood cell disorder. In a normal blood cell, the red blood cell is disc-shaped, flexible and looks like a doughnut without a hole. They move through small blood vessels to supply oxygen to various parts the body. But in a patient with sickle cell disease, the red blood cells are hard, sticky and look like a sickle used in farming. Sickle cells, unlike normal red blood cells, die early, which leads to a constant shortage of red blood cells. In some cases, when sickle red blood cells travel through small blood vessels, they get stuck and clog the blood flow, which can cause acute chest pain and stroke.


Symptoms of Sickle cell disease

The signs and symptoms of sickle cell disease vary from person to person and usually appear around 6 months of age. They can be:

  • Anemia: Whereas red blood cells usually live for about 120 days before death and replacement, sickle cells typically die within 10 to 20 days, leaving a shortage of red blood cells. This blood shortage is called Anemia. Without enough blood cells, there won’t be enough supply of oxygen to the body parts and this cause fatigue.
  • Swelling of hands and feet: Most times, sickle red blood cells cause a blockage of the small blood vessels, thereby limiting the supply of blood to parts of the body. As a result, the hands and feet swell up.
  • Retarded growth: A shortage of red blood cell, which supply oxygen and nutrients to the body can cause growth retardation and delay puberty in teenagers.
  • Frequent infections: Sickle cells can damage the spleen and cause increasing vulnerability to infectious diseases. To prevent this, infants and children are constantly administered antibiotics to prevent potentially life threatening infections.


Types of sickle cell disease

Various types of SCD exist, among which are:


People who have HbSS inherit two sickle cell genes “S” from both parent. This type of SCD is commonly called sickle cell anemia and is the most severe form of the disease.



In this form of SCD, the patient inherits a sickle gene “S” from one parent, and a gene for abnormal hemoglobin called “C” from another parent.


HbS beta thalassemia

People who suffer this form of SCD inherit one sickle cell “S” gene from one parent and a beta thalassemia from another parent. Beta thalassemia are of two types; the “O” and “+”. Those with the HbS beta-O-thalassemia usually suffer severe form of SCD while people who have HbS beta-+-thalassemia tend to have milder form of SCD.


Other types of Sickle cell disease, which are rare, include HbSD, HbSE, and HbSO. People with these forms usually inherit one “S” gene from one parent and the other D, E, or O gene from another parent.


Causes of sickle cell disease

Sickle cell disease is genetic condition that occurs when a child receives two sickle cell genes from the parents.


Complications and treatments

Some of the complications and treatments of SCD include:

Small hand-foot syndrome

This is usually the first symptom of SCD. It is accompanied by a fever and can be treated by giving the patient pain relieving medications, such as Ibuprofen and aspirin, and also an increase in body fluids, like water.


This is a very common complication of SCD. The early death of red blood cells associated with sickle red blood cells causes a shortage of healthy red blood cells that can carry oxygen throughout the body. Anemia can be treated by avoiding multiple blood transfusions, which may lead to hemosiderosis due to iron overload and may cause damages on the liver, heart, pancreas, and other organs. It can also lead to diabetes mellitus.

Splenic sequestration

Most times, a large number of sickle cells gather and are trapped in the spleen. This causes the spleen to become swollen and large. Treatment of this kind is by blood transfusion. The expertise of a specialist is however needed in transfusing blood into the patient’s body.

Loss of vision

When the blood capillaries supplying oxygenated blood to the eyes become blocked, by sickle cells, and the retina become damaged, the patient will experience impairment in vision. This can be treated with a Laser.


Deep vein thrombosis (DVT) and Pulmonary embolism (PE)

Sickle red blood cells can increase blood coagulation and induce an increased risk of blood clot DVT or in PE if the blood clot moves from deep veins. DVT and PE cause can cause serious disabilities and, in some cases, death.


Prevention of sickle cell disease

To prevent sickle cell disease, seeing a genetic counselor before getting married and conception is important. It is advised that two persons who are carriers of sickle cell genes should not marry to prevent the eventual sickle cell children.



Down syndrome

Down syndrome (DS) is a genetic disorder that  occurs when there is an abnormal cell division, which results in an extra copy of chromosome 21. This extra genetic material is the cause of some developmental changes and physical features of DS.

A baby is typically born with 46 chromosomes, but in babies with Down syndrome, there is an extra copy of the chromosome, chromosome 21. This extra chromosome changes the baby’s body and brain development, which can cause mental and physical challenges for the baby.

People with Down syndrome usually look alike. But despite the similarities in facial appearances, each person has different abilities. They usually have low IQ and are slower to speak than other children.


Symptoms of Down syndrome

Down syndrome may be mild, moderate or severe. Some patients are healthy while others may have significant health challenges such as heart defects. Some of the common features of DS include:

  • Small head
  • Short neck
  • Protruding tongue
  • Small ears
  • Poor muscle tone
  • Small hands and feet
  • A single line across the palm of the hand
  • Shorter height as children and adults


Types of Down syndrome

There are three types of Down syndrome; nevertheless, without diagnosis it is hard to spot one type from another, because, the physical features remain the same.

Trisomy 21

In this type, which is about 96%, each cell in the body has 3 separate copies of chromosome 21 instead of the normal 2 copies.

Translocation Down syndrome

This can occur when a portion of chromosome 21 becomes translocated onto another chromosome, before or at conception. The child would have the two copies of chromosome 21 and yet another copy of genetic material from chromosome 21 attached to another chromosome.

Translocation Down syndrome accounts for a small percentage of people with DS.

Mosaic Down syndrome

This is a rare form of Down syndrome. In Mosaic DS the child or children have 3 copies of chromosome 21 in some cells and 2 copies in normal cells. They may have fewer features of the condition due to the presence of some normal cells with normal 2 copies of chromosome 21.


Is Down syndrome inherited?

Down syndrome actually occurs due to a mistake in cell division during early development of the fetus. However, translocation DS can be passed from parent to child. Nevertheless, only a small percentage of children with translocation DS inherited it from one of their parents.

In this case, one of the parents has some rearranged genetic material from chromosome 21 with no extra genetic material. He or she has no symptoms of DS, but can pass an unbalanced translocation to the child that will result in Down syndrome.


Causes and risk factors

The main cause of DS is the extra genetic material of chromosome 21, which leads to the physical features and developmental challenges that is seen among people with DS.

Some of the risk factors are:


The older a woman becomes, the greater the chances of having a child or children with Down syndrome. Women who are 35 years or older are at high risk of having their fetus affected by DS than women who become pregnant at their younger age.


Being carriers of genetic translocation for Down syndrome

As indicated above, both parents can pass the genetic translocation for Down syndrome on to their children.


Complications associated with Down syndrome

Heart defects: About half of the children with DS have some heart defects, which may be life threatening and may require surgical operations in early infancy.

Dementia: people with Down syndrome are at greater risk of dementia at older age, say 50 and above. Having DS also increases the chances of developing Alzheimer’s disease.

Leukemia: The children have increased risk of leukemia. Other complications include:

  • Obesity
  • Spinal problem
  • Seizures
  • Underactive thyroid


Life Expectancy of people with Down syndrome

Unlike in previous ages, life expectancy for people living with DS has dramatically increased. Some people can live for more than 60 years, depending on the severity of health complications.


There is no cure for people with DS; but some services can be offered to such people that can improve their physical and intellectual capabilities. These services include speech, occupational and physical therapy.