Sickle cell anemia

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Sickle cell anemia

Sickle cell anemia is an inherited disease in which the Red Blood Cells get deformed to abnormal crescent shape.
Haemoglobin is a protein inside red blood cells that carries oxygen. Sickle cell anemia is caused by an abnormal type of hemoglobin called hemoglobin S. Hemoglobin S distorts the shape of red blood cells, especially when exposed to low oxygen levels. Hemoglobin S distorts the shape of red blood cells, especially when exposed to low oxygen levels. The distorted red blood cells are shaped like crescents or sickles. These fragile, sickle-shaped cells deliver less oxygen to the body’s tissues. They can also clog more easily in small blood vessels, and break into pieces that disrupt healthy blood flow.

Sickle cell disease is much more common in people of African and Mediterranean descent. It is also seen in people from South and Central America, the Caribbean, and the Middle East. This disease is inherited from both parents. Someone who inherits the hemoglobin S gene from one parent and normal hemoglobin (A) from the other parent will have sickle cell trait. People with sickle cell trait do not have the symptoms of true sickle cell anemia.
In several sections of Africa, the prevalence of sickle cell trait (heterozygote) is as high as 30%.
The sickle cell disease gene is present in approximately 8% of black Americans. More than 2 million people in the United States, nearly all of them of African American ancestry, carry the sickle gene.
Sickle cell disease is present mostly in blacks. But is also found, with much less frequency, in eastern Mediterranean and Middle East populations.
The male-to-female ratio is 1:1.
It is a lifelong condition. It first manifests in the second half of the first year of life and persists for the entire lifespan.

Symptoms
The abnormality of the RBCs in this disease results in serious infections, chronic anemia, and damage to body organs. Each person can have different forms of complications from the disorder. Some children remain relatively healthy, while others are frequently hospitalized.

The presenting symptoms of this disease involve pain and anemia.
For the first 6 months of life, infants are protected largely by elevated levels of Hb F (fetal haemoglobin). Patients have painful episodes lasting for hours or days. These episodes affect bones of back, long bones and chest. Some patients have episodes every few years and some have many episodes every year.

The most common clinical picture during adult life is vasoocclusive crisis. The crisis begins suddenly, sometimes because of some infection or temperature change, such as an air-conditioned environment during a hot summer day. Severe deep pain is present in the long bones. The abdomen is affected with severe pain resembling acute abdomen. Pain may be accompanied by fever, malaise, and leukocytosis (high white cell count ). The crisis may last several hours to several days and terminate as abruptly as it began.

Shortened finger of African Adult male with sickle cell Disease

During childhood and adolescence, the disease is associated with growth retardation, delayed sexual maturation. The spleen enlarges in the latter part of the first year of life. The spleen may undergoes repeated infarction. Over time, the spleen becomes fibrotic and shrinks. Another problem occurring in infancy is hand-foot syndrome. This is a painful swelling of the dorsum of the hand and foot.

Central nervous system involvement may cause stroke with neurological deficit.

The heart is involved due to chronic anemia and and microinfarcts may damage it. Repeated Blood transfusion causes hemosiderin deposition in the myocardium.
Formation of Bile Stones due to chronic hemolysis with hyperbilirubinemia may cause Cholicystitis.

The lungs develop areas of microinfarction. The resulting areas that lack oxygenation aggravate the sickling process. Pulmonary hypertension may develop.
Leg ulcers are a chronic painful problem. They result from minor injury to the area around the malleoli.
Priapism (painful erection of penis) is a troubesome complication and tends to occur repeatedly. When it is prolonged, it may lead to impotence.
Spontaneous abortions may occur those who get pregnant.

Treatment

No cure is available for this disease.

The goals of treating sickle cell anemia are to relieve pain, prevent infections, organ damage, and strokes, and control other complications.
Children who are diagnosed with this disease need antibiotics to prevent infections and their parents need to be educated in managing the child.
Mild pain can be treated at home but for severe pain hospital treatment is needed. Dehydration and infections have to be managed. Oxygen therapy may be needed.

Hydroxyurea: can be used in patients of Sickle Cell Anaemia. It prompts the body to make fetal hemoglobin. Fetal hemoglobin, or hemoglobin F, is the type of hemoglobin that newborns have. In people who have sickle cell anemia, fetal hemoglobin helps prevent red blood cells from sickling and improves anemia. Given daily, hydroxyurea reduces how often painful sickle cell crises and acute chest syndrome occur. Many people taking hydroxyurea also need fewer blood transfusions and have fewer hospital visits.

Blood Transfusion is needed to treat anaemia and complications.
Infections can be a major complication of sickle cell anemia throughout life, but especially during childhood. Infection in children can be managed by giving daily doses of antibiotics.
All routine vaccinations (including a yearly flu shot), plus the pneumococcal vaccine is important.
Sickle cell anemia can damage the blood vessels in the eyes and the retinas. Regular eye checkup is needed.
Leg ulcers due to sickle cell anemia can be very painful. Ulcers can be treated with cleansing solutions and medicated creams or ointments.
Gallbladder surgery may be needed if the presence of gallstones leads to gallbladder disease.
Priapism (a painful erection in males) can be treated with fluids, medicines, or surgery.
Young children who have sickle cell anemia should have regular checkups with a hematologist.

New Treatments: Research on blood and marrow stem cell transplants, gene therapy, and new medicines for sickle cell anemia is ongoing. The hope is that these studies will provide better treatments for the disease.

New Medicines:

Decitabine, like hydroxyurea, this medicine prompts the body to make fetal hemoglobin.

Adenosine A2a receptor agonists, these medicines may reduce pain-related complications.

5-HMF. This natural compound binds to red blood cells and increases their oxygen. This helps prevent the red blood cells from sickling.

Patau Syndrome

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Patau Syndrome

Patau syndrome is the least common and most severe of the viable autosomal trisomies. It is a genetic disorder in which a person has three copies of genetic material from chromosome 13, instead of the usual two copies.

Trisomy 13 occurs in about 1 out of every 10,000 newborns. Most cases are not inherited. Instead, the events that lead to Trisomy 13 occur in either the sperm or the egg that forms the fetus.

A significant number of cases that are trisomic for chromosome 13 end in spontaneous abortion, foetal demise, or stillbirth. More than 80% of children with trisomy 13 die in the first month.  Only one in 20 children survive longer than 6 months.

Symptoms

  • Extra fingers or toes (polydactyly). Clenched hands with outer fingers on top of the inner fingers.
  • Deformed feet, known as rocker-bottom feet
  • Severe mental deficiency. Small head, failure of the brain to divide into halves during gestation.
  • Facial defects such as small eyes, absent or malformed nose, cleft lip and/or cleft palate
  • Heart defects in 80% of individuals.
  • Kidney defects
  • Hernias: umbilical hernia, inguinal hernia.
  • Undescended testicle.

Edward's syndrome

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Edward’s syndrome

Edward’s syndrome was named after Dr. John Edward
Also called Trisomy 18. It is a form of rare genetic disorder where a portion of a person’s chromosome 18 is duplicated. Children with the syndrome inherit three instead of two, copies of chromosome eighteen.

The majority of people with the syndrome die during the foetal stage. Infants who survive experience serious defects and commonly live for short periods of time. Approximately 5-10% of children with Edward’s syndrome survive beyond their first year of life and these have severe developmental disabilities.

The syndrome occurs in about 1 in 5000 births. Edward’s syndrome affects more boys than girls. Women older than the age of thirty have a greater risk of bearing a child with the syndrome.

Ninety-five percent of children with Edward’s syndrome have what is referred to as, ‘full-trisomies,’ while two-percent are due to translocations where only a portion of an extra chromosome is present. Three-percent of children with Edward’s syndrome have what is referred to as, ‘mosaic tristomies,’ where the extra chromosome is there, but not in every one of the child’s cells.

Most cases of trisomy 18 are not inherited, but occur as random events during the formation of eggs and sperm. An error in cell division called nondisjunction results in a reproductive cell with an abnormal number of chromosomes.

Symptoms

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Majority die during the foetal stage.

  • Heads are unusually small, while the back of their head is prominent. Their ears are low-set and malformed, and their mouths and jaws are small.
  • Hands are often clenched into fists, with their index finger overlapping their other fingers.
  • Feet may be clubfeet, as well as toes that may be fused or webbed.
  • Many types of congenital heart disease like atrial septic defect, ventricular septal defect, or patent ductus arteriosus may be present.
  • Inguinal or umbilical hernia, abnormalities of their urogenital system, malformed kidneys, or undescended testicles in males may be seen.

Pick's Disease

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  Pick’s Disease

Synonym: Primary Progressive Aphasia

Arnold Pick, first described the disease in 1892

Pick’s disease is a rare disorder that affects the frontal and temporal lobes of the brain, which control speech and personality. These areas of brain undergo slow atrophy. It is therefore classified as a Frontotemporal dementia. 

Pick’s disease is a rare and permanent form of dementia that is similar to Alzheimer’s disease, except that it tends to affect only certain areas of the brain.

In Alzheimer’s disease memory loss is the predominate and early sign.

Patients with Pick’s initially exhibit marked personality and behavioural changes, and then a decline in the ability to speak coherently.

This disease is the result of a build-up of protein in the affected areas of the brain. The accumulation of abnormal brain cells, known as Pick Cells or Pick’s bodies, eventually leads to changes in character, socially inappropriate behaviour, and poor decision making, progressing to a severe impairment in intellect, memory and speech.

Pick Cells have characteristic of ballooned neurons with dissolution of chromatin.

Age of onset is between 40 and 60.

Frontal lobes of brain are responsible for rational emotional responses and the way we act in response to the world around us. In Pick’s Disease it is these frontal lobes that are involved in the disease process. These areas of brain are also responsible for speech and the use of language. As Pick’s disease involves this area of the brain these thinking processes are abnormal in the patients of Pick’s disease.

The earliest symptoms are usually changes in behaviour, mood, or personality. The person does not behave his or her usual self.

Some specific features:

  • Impulsivity and poor judgment in usually cautious person.
  • Sexual exhibitionism or promiscuity
  • Repetitive or obsessive behaviour
  • Rudeness, impatience, or aggression
  • Easily distracted; poor attention span
  • Lack of warmth, concern, or empathy
  • Loss of vocabulary, Speech problems: The person may have trouble finding the right word. His or her sentences may be incomplete or organized strangely.
  • Difficulty speaking or understanding speech.
  • Repeating words others say.
  • Weak, uncoordinated speech sounds.
  • Decrease in ability to read or write.
  • Complete loss of speech.
  • Changes in eating habits: The person may begin overeating, eating greedily, eating excessive amounts of sweets, or drinking large amounts of alcohol. He or she may gain weight.

Diagnosis

Only way to diagnose definitely is by a Biopsy of brain tissue. This can be done by a neurosurgeon. Otherwise the disease can be suspected on the basis of symptoms.

Single-photon emission computed tomography (SPECT) or positron-emission tomography (PET) scan: This scans are used in certain cases when the diagnosis is doubtful. They are especially good at detecting abnormal brain function. SPECT and PET scans are available only at some large medical centres.

Brain specimens showing Frontal Lobes thinning in Pick's Disease


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There is no cure for Pick disease. Treatment for the patients of this disease can be aimed at improving behaviour and mood problems and relieving other symptoms. For example, a speech therapist may be able to help the person improve his or her ability to communicate. Medication is helpful in many patients in easing mood and emotional difficulties.

Dementia
Parkinson’s Disease
Alzheimer’s disease

Creutzfeldt-Jakob Disease

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Creutzfeldt-Jakob Disease (“CJD”) is a rare, fatal brain disorder which causes a rapid, progressive dementia and associated neuromuscular disturbances

Incidence of this disease is One in per million people per year.
Affects both men and women of diverse ethnic backgrounds usually between the ages of 50 to 75 years. The disease occurs world wide.

Cause of the Disease

There had been much debate on the cause of the disease. Now it is accepted that that a transmissible agent is responsible for causing Creutzfeldt-Jakob Disease, as shown by experiments involving the injection of CJD-affected brains into the normal brains of healthy animals. The identification of this transmissible agent has been the subject of much scientific inquiry and debate.

Prion

The agent responsible is either a slow virus or Prion.

In 1996, scientists confirmed that they had discovered a new strain or variant of the disease among young people This is now referred to as vCJD.

The emergence of vCJD came after the biggest ever epidemic of BSE in cattle. Since that epidemic was in the UK and most vCJD victims lived in the UK, most scientists believed the two were linked.

They say the most likely cause of vCJD in humans was eating BSE-infected beef between the years of 1986 and 1989, when contaminated meat probably got into the food chain in large quantities.

Mode of Transmission

There appear to be three general categories for classifying the means through which CJD may be acquired.
First, the disease can occur sporadically.
Second, the disease can be inherited.
Third, the disease can be transmitted through infection.

Sporadic Creutzfeldt-Jakob Disease

Sporadic CJD refers to those cases in which there is no known infectious source and no evidence of the disease in the prior or subsequent generations of the patient’s family. Most CJD cases occur sporadically, thereby leaving their origins a mystery.

Inherited Creutzfeldt-Jakob Disease

Approximately 10 to 15 per cent of CJD cases are inherited. These familial cases exhibit a mutation in the gene coding for the prion protein. Genetic factors are thought to be responsible for the elevated numbers of CJD cases in some communities in Czechoslovakia and Chile, as well as among Libyan-born Jews.

Creutzfeldt-Jakob Disease Through Infection

Although CJD can be aquired by a transmissible agent it is not a contagious disease. The family members do not have increased risk of contracting the disease.
Iatrogenic transmission of CJD has occurred in cases involving
corneal transplants,
implantation of electrodes in the brain,
duramater grafts,
contaminated surgical instruments
and the injection of natural human growth hormone derived from cadaveric pituitaries.

Thus, one may become infected with CJD from direct contamination with infected neural tissue.

Studies are currently being conducted to determine if CJD is transmitted to humans through blood. The infectious agent has been found in blood but there have been no documented cases of blood transmission of CJD in humans.

In Britain, scientists have struggled to ascertain if there is a connection between bovine spongiform encephalopathy (“BSE”) and CJD. BSE or “mad cow disease” was initially discovered in Britain in 1986 and thought to have resulted from the use of cattle feed containing ground offal from scrapie-infected sheep.
It is now believed that here was a possible link between BSE and CJD. This new acknowledgement arose from the identification of an apparently new strain of CJD which was discovered in 10 people under the age of 42, including some teenagers. Additionally, five of the people were associated with the meat and livestock industry. Scientists decided that the most likely explanation for this unusual outbreak was the consumption of beef from diseased cattle before 1989, when regulations were adopted for the disposal of potentially infectious cattle offal, including brains, and the use of sheep entrails as feed ceased.