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This article is about the disease itself. For the genetic transmission of sickle-cell disease and its carrier state, see sickle cell trait. Sickle cell trait describes the way a person can inherit one of the genes of sickle cell disease but not develop recurrent symptoms
Sickle-cell disease
Classification and external resources
Sickle-shaped red blood cells
ICD-10 D57.
ICD-9 282.6
OMIM 603903
DiseasesDB 12069
MedlinePlus 000527
eMedicine med/2126  oph/490 ped/2096 emerg/26 emerg/406
MeSH C15.378.071.141.150.150

Sickle-cell disease or sickle-cell anaemia (or anemia) is a blood disorder characterized by red blood cells that assume an abnormal, rigid, sickle shape. The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify Diseases The International Statistical Classification of Diseases and Related Health Problems 10th Revision ( ICD -10) is a coding of diseases and signs symptoms abnormal findings The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify Diseases The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. The Mendelian Inheritance in Man project is a Database that catalogues all the known Diseases with a genetic component, and—when possible—links them The Diseases Database is a free Website that provides information about the relationships between medical conditions Symptoms, and Medications. MedlinePlus, with the MedlinePlus Medical Encyclopedia, is a website network containing Health information from the world's largest medical Library eMedicine is an online clinical medical knowledge base that was founded in 1996 by Scott Plantz and Richard Lavely two medical doctors Medical Subject Headings ( MeSH) is a huge Controlled vocabulary (or metadata system for the purpose of indexing journal articles and books Hematology ( American English) or haematology ( British English) is the branch of biology (physiology Pathology, Clinical laboratory Red blood cells are the most common type of Blood cell and the Vertebrate body's principal means of delivering Oxygen to the body tissues via the Blood A sickle is a hand-held Agricultural Tool with a curved Blade typically used for harvesting grain crop or cutting grass for Hay. Sickling decreases the cells' flexibility and results in their restricted movement through blood vessels, depriving downstream tissues of oxygen. The blood vessels are part of the Circulatory system and function to transport Blood throughout the body Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the The disease is chronic and lifelong: individuals are most often well, but their lives are punctuated by periodic painful attacks and a risk of various other complications. Life expectancy is shortened, with older studies reporting an average life expectancy of 42 and 48 years for males and females, respectively.

Sickle-cell disease occurs more commonly in people (or their descendants) from parts of the world such as sub-Saharan Africa, where malaria is or was common, but it also occurs in people of other ethnicities. Sub-Saharan Africa is a geographical term used to describe the area of the African continent which lies south of the Sahara, or those African countries Malaria is a vector -borne Infectious disease caused by Protozoan Parasites It is widespread in tropical and subtropical regions including This is because those with one or two alleles of the sickle-cell disease are resistant to malaria since the sickle red blood cells are not conducive to the parasites - in areas where malaria is common there is a survival value in carrying the sickle-cell genes. An allele (ˈæliːl (UK /əˈliːl/ (US (from the Greek αλληλος allelos, meaning each other) is one member of a pair or series of different forms eVolution is the third Album by eLDee, it was due to be released in 2008

Contents

Classification

Sickle-cell anaemia is the name of a specific form of sickle-cell disease in which there is homozygosity for the mutation that causes HbS. Zygosity refers to the genetic condition of a Zygote. In genetics zygosity describes the similarity or dissimilarity of DNA between Homologous In biology mutations are changes to the Nucleotide sequence of the Genetic material of an organism Sickle-cell anaemia is also referred to as "HbSS", "SS disease", "haemoglobin S", or permutations thereof. Other, rarer forms of sickle-cell disease include sickle-haemoglobin C disease (HbSC), sickle beta-plus-thalassaemia (HbS/β+) and sickle beta-zero-thalassaemia (HbS/β0). Hemoglobin C (abbreviated as Hb C or HbC) is an abnormal Hemoglobin with substitution of a Lysine residue for Glutamic acid residue Thalassemia (from Greek θαλασσα thalassa sea + αίμα haima blood British spelling "thalassaemia" is an inherited Autosomal recessive These other forms of sickle-cell disease are compound heterozygous states in which the person has only one copy of the mutation that causes HbS and one copy of another abnormal haemoglobin allele. Two Recessive alleles that can cause a particular disease in a Heterozygous state Hemoglobin ( also spelled haemoglobin and abbreviated Hb or Hgb) is the Iron -containing Oxygen -transport Metalloprotein An allele (ˈæliːl (UK /əˈliːl/ (US (from the Greek αλληλος allelos, meaning each other) is one member of a pair or series of different forms

The term "disease" is applied since the inherited abnormality causes a pathological condition that can lead to death and severe complications. Not all inherited variants of haemoglobin are detrimental, a concept known as genetic polymorphism. Polymorphism in biology occurs when two or more clearly different Phenotypes exist in the same population of a species — in other words the occurrence of more than one

Signs and symptoms

Sickle-cell disease may lead to various acute and chronic complications, several of which are potentially lethal.

Vaso-occlusive crisis

The vaso-occlusive crisis is caused by sickle-shaped red blood cells that obstruct capillaries and restrict blood flow to an organ, resulting in ischemia, pain, and organ damage. A vaso-occlusive crisis or sickle cell crisis is a common painful complication of Sickle cell anemia in adolescents and adults In Medicine, ischemia ( Greek ισχαιμία, isch- is restriction hema or haema is Blood) is a restriction Pain, in the sense of physical pain, is a typical sensory experience that may be described as the unpleasant awareness of a noxious stimulus or bodily harm The frequency, severity, and duration of these crises varies considerably. Painful crises are treated with hydration and analgesics; pain management requires opioid administration at regular intervals until the crisis has settled. For other uses see Opiate (disambiguation, or for the class of drugs see Opioid. For milder crises a subgroup of patients manage on NSAIDs (such as diclofenac or naproxen). Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAID s or NAID s, are drugs with Analgesic, Antipyretic and in higher Diclofenac (marketed as Flector patch, Voltaren, Voltarol, Diclon, Dicloflex Difen, Difene, Cataflam Naproxen ( INN) (nəˈprɒksən is a Non-steroidal anti-inflammatory drug (NSAID commonly used for the reduction of moderate to severe Pain, Fever For more severe crises most patients require inpatient management for intravenous opioids; patient-controlled analgesia (PCA) devices are commonly used in this setting. Patient-controlled analgesia ( PCA) is any method of allowing a person in Pain to administer their own pain relief Diphenhydramine is effective for the itching associated with the opioid use. Pharmacological action Diphenhydramine (dye fen hye' dra meen works by blocking the effect of histamine at H1 receptor sites Incentive spirometry, a technique to encourage deep breathing to minimise the development of atelectasis, is recommended. Atelectasis is a collapse of lung tissue affecting part or all of one lung

Because of its narrow vessels and function in clearing defective red blood cells, the spleen is frequently affected. The spleen is an organ found in all Vertebrate animals In humans the spleen is located in the abdomen of the body where it functions in the destruction of redundant Red It is usually infarcted before the end of childhood in individuals suffering from sickle-cell anaemia. In Medicine, an infarction is the process resulting in a Macroscopic area of necrotic tissue in some organ caused by loss of adequate Blood supply This autosplenectomy increases the risk of infection from encapsulated organisms;[1][2] preventive antibiotics and vaccinations are recommended for those with such asplenia. An autosplenectomy (from 'auto-' self '-splen-' spleen ' -ectomy ' removal occurs when a Disease damages the Spleen to Polysaccharide encapsulated bacteria, frequently referred to simply as encapsulated bacteria and less precisely called encapsulated organisms, are a group This article is about the medical condition For the Moth Genus, see Armadini.

A recognised type of sickle crisis is the acute chest syndrome, a condition characterised by fever, chest pain, difficulty breathing, and pulmonary infiltrate on a chest X-ray. The acute chest syndrome is a vasoocclusive crisis of the Pulmonary Vasculature commonly seen in patients with Sickle cell anemia. A chest X-ray, commonly abbreviated CXR, is a projection radiograph ( X-ray) taken by a Radiographer, of the Thorax which is used Given that pneumonia and sickling in the lung can both produce these symptoms, the patient is treated for both conditions. It can be triggered by painful crisis, respiratory infection, bone-marrow embolisation, or possibly by atelectasis, such as can be caused by opiate administration, or surgery.

Other sickle-cell crises

Complications

Sickle-cell anaemia can lead to various complications, including:

Heterozygotes

The heterozygous form (sickle cell trait) is almost always asymptomatic and the only significant manifestation is the renal concentrating defect presenting with isosthenuria. Isosthenuria refers to the excretion of urine the specific gravity (concentration of which is neither greater (more concentrated nor less (more dilute than that of protein-free

Diagnosis

In HbSS, the full blood count reveals haemoglobin levels in the range of 6-8 g/dL with a high reticulocyte count (as the bone marrow compensates for the destruction of sickle cells by producing more red blood cells). A complete blood count ( CBC) also known as full blood count ( FBC) or full blood exam ( FBE) or blood panel, is Hemoglobin ( also spelled haemoglobin and abbreviated Hb or Hgb) is the Iron -containing Oxygen -transport Metalloprotein Reticulocytes are immature Red blood cells typically composing about 1% of the red cells in the human body In other forms of sickle cell disease, Hb levels tend to be higher. A blood film may show features of hyposplenism (target cells and Howell-Jolly bodies). A Blood Film or Peripheral Blood Smear is a slide made from a drop of Blood, that allows the cells to be examined microscopically This article is about the medical condition For the Moth Genus, see Armadini. Codocytes, also known as target cells, are red blood cells that have the appearance of a target with a Bullseye. Howell-Jolly bodies are histopathological findings of basophilic nuclear remnants (clusters of DNA) in circulating erythrocytes

Sickling of the red blood cells, on a blood film, can be induced by the addition of sodium metabisulfite. Sodium metabisulfite or sodium pyrosulfite (IUPAC spelling Br The presence of sickle haemoglobin can also be demonstrated with the "sickle solubility test". A mixture of haemoglobin S (Hb S) in a reducing solution (such as sodium dithionite) gives a turbid appearance while normal Hb gives a clear solution. Sodium dithionite (aka sodium hydrosulfite or sodium hydrosulphite is a white Crystalline powder with a weak Sulfurous odor

Abnormal haemoglobin forms can be detected on haemoglobin electrophoresis, a form of gel electrophoresis on which the various types of haemoglobin move at varying speed. Hemoglobin ( also spelled haemoglobin and abbreviated Hb or Hgb) is the Iron -containing Oxygen -transport Metalloprotein Sickle-cell haemoglobin (HgbS) and haemoglobin C with sickling (HgbSC)—the two most common forms—can be identified from there. Hemoglobin C (abbreviated as Hb C or HbC) is an abnormal Hemoglobin with substitution of a Lysine residue for Glutamic acid residue The diagnosis can be confirmed with high performance liquid chromatography (HPLC). High-performance liquid chromatography (or High pressure liquid chromatography, HPLC) is a form of Column chromatography used frequently in Biochemistry Genetic testing is rarely performed, as other investigations are highly specific for HbS and HbC. Genetic testing allows the genetic Diagnosis of vulnerabilities to inherited Diseases, and can also be used to determine a person's Ancestry. [6]

Pathophysiology

Sickle-cell anaemia is caused by a point mutation in the β-globin chain of haemoglobin, causing the amino acid glutamic acid to be replaced with the less polar amino acid valine at the sixth position. A point mutation, or single base substitution, is a type of Mutation that causes the replacement of a single base nucleotide with another nucleotide of the genetic Hemoglobin ( also spelled haemoglobin and abbreviated Hb or Hgb) is the Iron -containing Oxygen -transport Metalloprotein Glutamic acid (abbreviated as Glu or E) is one of the 20 Alpha Amino acids It is not among the human Essential amino acids Its Valine (abbreviated as Val or V) is an α- Amino acid with the Chemical formula HO2CCH(NH2CH(CH32 The β-globin gene is found on the short arm of chromosome 11. Chromosome 11 is one of the 23 pairs of Chromosomes in Humans People normally have two copies of this chromosome The association of two wild-type α-globin subunits with two mutant β-globin subunits forms haemoglobin S (HbS). A mutant is an individual organism or new genetic character arising or resulting from an instance of Mutation, which is a base-pair sequence change within the DNA Under low oxygen conditions, the absence of a polar amino acid at position six of the β-globin chain promotes the polymerisation of haemoglobin, which distorts red blood cells into a sickle shape and decreases their elasticity.

The loss of red blood cell elasticity is central to the pathophysiology of sickle-cell disease. Normal red blood cells are quite elastic, which allows the cells to deform to pass through capillaries. In sickle-cell disease, low oxygen tension promotes red blood cell sickling and repeated episodes of sickling damage the cell membrane and decrease the cell's elasticity. These cells fail to return to normal shape when normal oxygen tension is restored. Consequently, these rigid blood cells are unable to deform as they pass through narrow capillaries, leading to vessel occlusion and ischaemia. In Medicine, ischemia ( Greek ισχαιμία, isch- is restriction hema or haema is Blood) is a restriction

Genetics

A single amino acid change causes haemoglobin proteins to form fibers.
A single amino acid change causes haemoglobin proteins to form fibers.

Sickle cell gene mutation probably arose spontaneously in different geographic areas as suggested by restriction endonuclease analysis. These clinically important variants are known as Cameroon, Senegal, Benin, Bantu and Saudi-Asian. Their clinical importance springs from the fact that some of them are associated with higher HbF levels e. g Senegal and Saudi-Asian variants, and tend to have milder disease. [7]

In people heterozygous for HgbS (carriers of sickling haemoglobin), the polymerisation problems are minor. Zygosity refers to the genetic condition of a Zygote. In genetics zygosity describes the similarity or dissimilarity of DNA between Homologous A genetic carrier (or just carrier) is a person or other organism that has inherited a genetic trait or Mutation, but who does not display that In people homozygous for HgbS, the presence of long chain polymers of HbS distort the shape of the red blood cell, from a smooth donut-like shape to ragged and full of spikes, making it fragile and susceptible to breaking within capillaries. Zygosity refers to the genetic condition of a Zygote. In genetics zygosity describes the similarity or dissimilarity of DNA between Homologous A doughnut (also spelled "donut" is a sweet Deep-fried piece of Dough or batter. Capillaries are the smallest of a body's Blood vessels measuring 5-10 μm in diameter which connect Arterioles and Venules and enable the interchange Carriers only have symptoms if they are deprived of oxygen (for example, while climbing a mountain) or while severely dehydrated. Dehydration ( hypohydration) is the removal of Water ( hydro in ancient Greek) from an object Normally these painful crises occur 0. 8 times per year per patient. The sickle-cell disease occurs when the seventh amino acid (if we count the initial methionine), glutamic acid is replaced by valine to change its structure and function.

Distribution of the sickle-cell trait
Distribution of the sickle-cell trait
Distribution of malaria
Distribution of malaria

The gene defect is a known mutation of a single nucleotide (see single nucleotide polymorphism - SNP) (A to T) of the β-globin gene, which results in glutamate to be substituted by valine at position 6. Malaria is a vector -borne Infectious disease caused by Protozoan Parasites It is widespread in tropical and subtropical regions including In biology mutations are changes to the Nucleotide sequence of the Genetic material of an organism Nucleotides are Organic compounds that consist of three joined structures a nitrogenous base a Sugar, and a Phosphate group A single nucleotide polymorphism ( SNP, pronounced snip) is a DNA sequence variation occurring when a single Nucleotide - A, T Glutamic acid (abbreviated as Glu or E) is one of the 20 Alpha Amino acids It is not among the human Essential amino acids Its Valine (abbreviated as Val or V) is an α- Amino acid with the Chemical formula HO2CCH(NH2CH(CH32 Haemoglobin S with this mutation are referred to as HbS, as opposed to the normal adult HbA. The genetic disorder is due to the mutation of a single nucleotide, from a GAG to GUG codon mutation. In biology mutations are changes to the Nucleotide sequence of the Genetic material of an organism The genetic code is the set of rules by which information encoded in genetic material ( DNA or RNA sequences is translated into Proteins In biology mutations are changes to the Nucleotide sequence of the Genetic material of an organism This is normally a benign mutation, causing no apparent effects on the secondary, tertiary, or quaternary structure of haemoglobin. In Biochemistry and Structural biology, secondary structure is the general three-dimensional form of local segments of Biopolymers such as In Biochemistry and Chemistry, the tertiary structure of a Protein or any other Macromolecule is its three-dimensional structure as defined In Biochemistry, quaternary structure is the arrangement of multiple folded Protein molecules in a multi-subunit complex What it does allow for, under conditions of low oxygen concentration, is the polymerization of the HbS itself. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the In Polymer chemistry, polymerization is a process of reacting Monomer Molecules together in a Chemical reaction to form three-dimensional networks The deoxy form of haemoglobin exposes a hydrophobic patch on the protein between the E and F helices. The hydrophobic residues of the valine at position 6 of the beta chain in haemoglobin are able to bind to the hydrophobic patch, causing haemoglobin S molecules to aggregate and form fibrous precipitates.

The allele responsible for sickle-cell anaemia is autosomal recessive and can be found on the short arm of chromosome 11. An allele (ˈæliːl (UK /əˈliːl/ (US (from the Greek αλληλος allelos, meaning each other) is one member of a pair or series of different forms A person who receives the defective gene from both father and mother develops the disease; a person who receives one defective and one healthy allele remains healthy, but can pass on the disease and is known as a carrier. A genetic carrier (or just carrier) is a person or other organism that has inherited a genetic trait or Mutation, but who does not display that If two parents who are carriers have a child, there is a 1-in-4 chance of their child developing the disease and a 1-in-2 chance of their child just being a carrier. Since the gene is incompletely recessive, carriers have a few sickle red blood cells at all times, not enough to cause symptoms, but enough to give resistance to malaria. Sickle cell trait describes the way a person can inherit one of the genes of sickle cell disease but not develop recurrent symptoms Because of this, heterozygotes have a higher fitness than either of the homozygotes. Fitness (often denoted w in Population genetics models is a central concept in evolutionary theory. This is known as heterozygote advantage. A heterozygote advantage ( heterozygous advantage) describes the case in which the heterozygote genotype has a higher relative fitness than either the

Due to the evolutionary advantage of the heterozygote, the disease is still prevalent, especially among people with recent ancestry in malaria-stricken areas, such as Africa, the Mediterranean, India and the Middle East. India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country The Middle East is a Subcontinent with no clear boundaries often used as a synonym to Near East, in opposition to Far East. [8]

The Price equation is a simplified mathematical model of the genetic evolution of sickle-cell anaemia. The Price equation (also known as Price's equation) is a covariance equation which is a mathematical description of Evolution and Natural selection.

The malaria parasite has a complex life cycle and spends part of it in red blood cells. In a carrier, the presence of the malaria parasite causes the red blood cell to rupture, making the plasmodium unable to reproduce. A plasmodium is also the macroscopic form of the Protist known as a Slime mould. Further, the polymerization of Hb affects the ability of the parasite to digest Hb in the first place. Therefore, in areas where malaria is a problem, people's chances of survival actually increase if they carry sickle-cell trait (selection for the heterozygote).

In the USA, where there is no endemic malaria, the prevalence of sickle-cell anaemia amongst African Americans is lower (about 0. The United States of America —commonly referred to as the African Americans or Black Americans are citizens or residents of the United States who have origins in any of the black populations of Africa 25%) than in West Africa (about 4. West Africa or Western Africa is the Westernmost Region of the African Continent. 0%) and is falling. Without endemic malaria from Africa, the condition is purely disadvantageous, and will tend to be bred out of the affected population.

Sickle-cell disease is inherited in the autosomal recessive pattern.
Sickle-cell disease is inherited in the autosomal recessive pattern.

Inheritance

  1. If one parent has sickle-cell anaemia (SS) and the other has sickle-cell trait (AS), there is a 50% chance (or 1 out of 2) of a child having sickle-cell disease (SS) and a 50% chance of a child having sickle-cell trait (AS).
  2. When both parents have sickle-cell trait (AS), they have a 25% chance (1 of 4) of a child having sickle-cell disease (SS), as shown in the diagram.

Sickle-cell anaemia appears to be caused by a recessive allele. Two carrier parents have a one in four chance of having a child with the disease. The child will be homozygous recessive.

It has been argued that the allele, although appearing outwardly recessive, is in fact co-dominant, due to the resistance to a malaria which is obtained by those of the AS genotype. Since a separate phenotype from that of Normal (AA) has therefore been expressed, it is impossible to argue that the S allele is homozygous recessive.

Treatment

Painful (vaso-occlusive) crises

Most people with sickle-cell disease have intensely painful episodes called vaso-occlusive crises. The frequency, severity, and duration of these crises, however, vary tremendously. Painful crises are treated symptomatically with analgesics; pain management requires opioid administration at regular intervals until the crisis has settled. An opioid is a chemical Substance that has a Morphine -like action in the body For milder crises a subgroup of patients manage on NSAIDs (such as diclofenac or naproxen). Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAID s or NAID s, are drugs with Analgesic, Antipyretic and in higher Diclofenac (marketed as Flector patch, Voltaren, Voltarol, Diclon, Dicloflex Difen, Difene, Cataflam Naproxen ( INN) (nəˈprɒksən is a Non-steroidal anti-inflammatory drug (NSAID commonly used for the reduction of moderate to severe Pain, Fever For more severe crises most patients require inpatient management for intravenous opioids; patient-controlled analgesia (PCA) devices are commonly used in this setting. Patient-controlled analgesia ( PCA) is any method of allowing a person in Pain to administer their own pain relief Diphenhydramine is also an effective agent that is frequently prescribed by doctors in order to help control any itching associated with the use of opioids. Pharmacological action Diphenhydramine (dye fen hye' dra meen works by blocking the effect of histamine at H1 receptor sites

Acute chest crises

Management is similar to vaso-occlusive crises with the addition of antibiotics (usually a quinolone or macrolide, since wall-deficient ["atypical"] bacteria are thought to contribute to the syndrome),[9] oxygen supplementation for hypoxia, and close observation. Chronic Hypoxia is a pathological condition in which the body as a whole ( generalized hypoxia) or region of the body ( tissue hypoxia) is deprived of adequate Should the pulmonary infiltrate worsen or the oxygen requirements increase, simple blood transfusion or exchange transfusion is indicated. Blood transfusion is the process of transferring Blood or blood-based products from one person into the Circulatory system of another An exchange transfusion is a medical treatment in which Apheresis is used to remove one person's Red blood cells or Platelets and replace them with transfused The latter involves the exchange of a significant portion of the patients red cell mass for normal red cells, which decreases the percent haemoglobin S in the patient's blood.

Hydroxyurea

The first approved drug for the causative treatment of sickle-cell anaemia, hydroxyurea, was shown to decrease the number and severity of attacks in a study in 1995 (Charache et al)[10] and shown to possibly increase survival time in a study in 2003 (Steinberg et al). Hydroxyurea or hydroxycarbamide (the latter being the recommended International Nonproprietary Name) is an Antineoplastic drug used in hematological [11] This is achieved, in part, by reactivating fetal haemoglobin production in place of the haemoglobin S that causes sickle-cell anaemia. Hydroxyurea had previously been used as a chemotherapy agent, and there is some concern that long-term use may be harmful, but this risk has been shown to be either absent or very small and it is likely that the benefits outweigh the risks. Chemotherapy, in its most general sense refers to treatment of disease by chemicals that kill cells specifically those of micro-organisms or Cancer. [12]

Bone marrow transplants

Bone marrow transplants have proven to be effective in children.

Future treatments

Various approaches are being sought for preventing sickling episodes as well as for the complications of sickle-cell disease. Other ways to modify hemoglobin switching are being investigated, including the use of phytochemicals such as nicosan. Phytochemicals are plant-derived chemical compounds under scientific research for their potential health-promoting properties but with unproved benefits Nicosan ( Hemoxin in US previously Niprisan or Nix-0699 is a Phytochemical (ethanol/water extract of Piper guineenses seeds Pterocapus Gene therapy is under investigation. Gene therapy is the insertion of Genes into an individual's cells and tissues to treat a Disease, and Hereditary diseases in which a

Situation of carriers

People who are known carriers of the disease often undergo genetic counseling before they have a child. Genetic counseling is the process by which patients or relatives at risk of an inherited disorder are advised of the consequences and nature of the disorder the probability of developing A test to see if an unborn child has the disease takes either a blood sample from the unborn or a sample of amniotic fluid. Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells such as nutrients and oxygen—and transports Waste products Amniotic fluid or liquor amnii is the nourishing and protecting liquid contained by the Amnion of a pregnant woman Since taking a blood sample from a fetus has risks, the latter test is usually used.

After the mutation responsible for this disease was discovered in 1979, the U.S. Air Force required African American applicants to test for the mutation. Year 1979 ( MCMLXXIX) was a Common year starting on Monday (link displays the 1979 Gregorian calendar) It dismissed 143 applicants because they were carriers, even though none of them had the condition. It eventually withdrew the requirement, but only after a trainee filed a lawsuit.

History

This collection of clinical findings was unknown until the explanation of the sickle cells in 1904 by the Chicago cardiologist and professor of medicine James B. Herrick (1861-1954) whose intern Ernest Edward Irons (1877-1959) found "peculiar elongated and sickle shaped" cells in the blood of Walter Clement Noel, a 20 year old first year dental student from Grenada after Noel was admitted to the Chicago Presbyterian Hospital in December 1904 suffering from anaemia. James Bryan Herrick ( August 11, 1861 - March 7, 1954) was as American doctor who is credited with the description of several important Year 1904 ( MCMIV) was a Leap year starting on Friday (link will display calendar of the Gregorian calendar (or a Leap year starting on Anemia ( AmE) or anæmia/anaemia ( BrE) (from the Ancient Greek grc-Latn anaîmia, meaning “without blood” is defined as a qualitative Noel was readmitted several times over the next three years for "muscular rheumatism" and "bilious attacks". Noel completed his studies and returned to the capital of Grenada (St. George's) to practice dentistry. Dentistry' is the "evaluation diagnosis prevention and/or treatment (nonsurgical surgical or related procedures of diseases disorders and/or conditions of the oral cavity He died of pneumonia in 1916 and is buried in the Catholic cemetery at Sauteurs in the north of Grenada. Pneumonia is an inflammatory illness of the Lung. Frequently it is described as lung Parenchyma / alveolar inflammation and abnormal Year 1916 ( MCMXVI) was a Leap year starting on Saturday (link will display the full calendar of the Gregorian calendar (or a Leap year Sauteurs is a fishing village in the Saint Patrick Parish Grenada and is the sixth largest in Grenada with a population of about 1300 [13]

The disease was named "sickle-cell anaemia" by Vernon Mason in 1922. Year 1922 ( MCMXXII) was a Common year starting on Sunday of the Gregorian calendar. In retrospect some elements of the disease had been recognized earlier: a paper in the Southern Journal of Medical Pharmacology in 1846 described the absence of a spleen in the autopsy of a runaway slave. An autopsy, also known as a post-mortem examination, necropsy, or obduction, is a Medical procedure that consists of a thorough Examination The African medical literature reported this condition in the 1870s where it was known locally as ogbanjes ("children who come and go") because of the very high infant mortality rate caused by this condition. A history of the condition tracked reports back to 1670 in one Ghanaian family. [14] Also, the practice of using tar soap to cover blemishes caused by sickle-cell sores was prevalent in the African American community.

Linus Pauling and colleagues were the first, in 1949, to demonstrate that sickle cell disease occurs as a result of an abnormality in the haemoglobin molecule. Linus Carl Pauling (February 28 1901 – August 19 1994 was an American Scientist, Peace activist, Author and educator. This was the first time a genetic disease was linked to a mutation of a specific protein, a milestone in the history of molecular biology. The history of molecular biology begins in the 1930s with the convergence of various previously distinct biological disciplines Biochemistry, Genetics, Microbiology

The origin of the mutation that led to the sickle-cell gene was initially thought to be in the Arabian peninsula, spreading to Asia and Africa. The Arabian Peninsula (in Arabic: شبه الجزيرة العربية šibh al-jazīra al-ʻarabīya or جزيرة العرب jazīrat al-ʻarab) It is now known, from evaluation of chromosome structures, that there have been at least four independent mutational events, three in Africa and a fourth in either Saudi Arabia or central India. [15] These independent events occurred between 3,000 and 6,000 generations ago, approximately 70-150,000 years.

Notes

  1. ^ Pearson H. "Sickle cell anaemia and severe infections due to encapsulated bacteria". J Infect Dis 136 Suppl: S25-30. PMID 330779.  
  2. ^ Wong W, Powars D, Chan L, Hiti A, Johnson C, Overturf G (1992). "Polysaccharide encapsulated bacterial infection in sickle cell anaemia: a thirty year epidemiologic experience". Am J Hematol 39 (3): 176-82. doi:10.1002/ajh.2830390305. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 1546714.  
  3. ^ Smith WR, Penberthy LT, Bovbjerg VE, et al (2008). "Daily assessment of pain in adults with sickle cell disease". Ann. Intern. Med. 148 (2): 94-101. PMID 18195334.  
  4. ^ Gladwin MT, Sachdev V, Jison ML, et al (2004). "Pulmonary hypertension as a risk factor for death in patients with sickle cell disease". N. Engl. J. Med. 350 (9): 886–95. doi:10.1056/NEJMoa035477. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 14985486.  
  5. ^ Powars DR, Elliott-Mills DD, Chan L, et al (1991). "Chronic renal failure in sickle cell disease: risk factors, clinical course, and mortality". Ann. Intern. Med. 115 (8): 614-20. PMID 1892333.  
  6. ^ Clarke GM, Higgins TN (2000). "Laboratory investigation of hemoglobinopathies and thalassemias: review and update". Clin. Chem. 46 (8 Pt 2): 1284-90. PMID 10926923.  
  7. ^ Green NS, Fabry ME, Kaptue-Noche L, Nagel RL (1993). "Senegal haplotype is associated with higher HbF than Benin and Cameroon haplotypes in African children with sickle cell anemia". Am. J. Hematol. 44 (2): 145-6. doi:10.1002/ajh.2830440214. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 7505527.  
  8. ^ Kwiatkowski DP (2005). "How malaria has affected the human genome and what human genetics can teach us about malaria". Am. J. Hum. Genet. 77 (2): 171-92. doi:10.1086/432519. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 16001361.   Full text at PMC: 1224522
  9. ^ Aldrich TK, Nagel RL. PubMed Central is a free digital database of full-text Scientific literature in biomedical and life sciences (1998). "Pulmonary Complications of Sickle Cell Disease. ", in Bone RC et al. , editors: Pulmonary and Critical Care Medicine, 6th edition, St. Louis: Mosby, pp. 1-10. ISBN 0-81511-371-4.  
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  14. ^ Konotey-Ahulu FID. Effect of environment on sickle cell disease in West Africa: epidemiologic and clinical considerations. In: Sickle Cell Disease, Diagnosis, Management, Education and Research. Abramson H, Bertles JF, Wethers DL, eds. CV Mosby Co, St. Louis. 1973; 20; cited in Desai, D. V. ; Hiren Dhanani (2004). "Sickle Cell Disease: History And Origin". The Internet Journal of Haematology 1 (2). ISSN 1540-2649. An International Standard Serial Number ( ISSN) is a unique eight-digit number used to identify a print or electronic Periodical publication.  
  15. ^ Desai, D. V. ; Hiren Dhanani (2004). "Sickle Cell Disease: History And Origin". The Internet Journal of Haematology 1 (2). ISSN 1540-2649. An International Standard Serial Number ( ISSN) is a unique eight-digit number used to identify a print or electronic Periodical publication.  

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Dictionary

sickle-cell disease

-noun

  1. (medicine) A disease characterized by sickle-shaped red blood cells.
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