A Primeview on Sickle Cell Disease !

Primeview:

Sickle cell disease (SCD) is a group of inherited disorders caused by mutations in HBB, which encodes haemoglobin subunit β. Haemoglobin molecules that include mutant sickle β-globin subunits can polymerize; erythrocytes that contain mostly haemoglobin polymers assume a sickled form and are prone to haemolysis. Other pathophysiological mechanisms that contribute to the SCD phenotype are vaso-occlusion and activation of the immune system. SCD is characterized by a remarkable phenotypic complexity. Common acute complications are acute pain events, acute chest syndrome and stroke; chronic complications (including chronic kidney disease) can damage all organs. Hydroxycarbamide, blood transfusions and haematopoietic stem cell transplantation can reduce the severity of the disease. Early diagnosis is crucial to improve survival, and universal newborn screening programmes have been implemented in some countries but are challenging in low-income, high-burden settings.

Sickle cell disease (SCD) is an umbrella term that defines a group of inherited diseases (including sickle cell anaemia (SCA), HbSC and HbSβ-thalassaemia) characterized by mutations in the gene encoding the haemoglobin subunit β (HBB). Haemoglobin (Hb) is a tetrameric protein composed of different combinations of globin subunits; each globin subunit is associated with the cofactor haem, which can carry a molecule of oxygen. Hb is expressed by red blood cells, both reticulocytes (immature red blood cells) and erythrocytes (mature red blood cells). Several genes encode different types of globin proteins, and their various tetrameric combinations generate multiple types of Hb, which are normally expressed at different stages of life — embryonic, fetal and adult. Hb A (HbA), the most abundant (>90%) form of adult Hb, comprises two α-globin subunits (encoded by the duplicated HBA1 and HBA2 genes) and two β-globin subunits.

A single nucleotide substitution in HBB results in the sickle Hb (HbS) allele βS; the mutant protein generated from the βS allele is the sickle β-globin subunit and has an amino acid substitution. Under conditions of deoxygenation (that is, when the Hb is not bound to oxygen), Hb tetramers that include two of these mutant sickle β-globin subunits (that is, HbS) can polymerize and cause the erythrocytes to assume a crescent or sickled shape from which the disease takes its name. Hb tetramers with one sickle β-globin subunit can also polymerize, albeit not as efficiently as HbS. Sickle erythrocytes can lead to recurrent vaso-occlusive episodes that are the hallmark of SCD. SCD is inherited as an autosomal codominant trait; individuals who are heterozygous for the βS allele carry the sickle cell trait (HbAS) but do not have SCD, whereas individuals who are homozygous for the βS allele have SCA. SCA, the most common form of SCD, is a lifelong disease characterized by chronic haemolytic anaemia, unpredictable episodes of pain and widespread organ damage.

This primeview focuses on SCA and aims to balance such remarkable advances with the key major challenges remaining worldwide to improve the prevention and management of this chronic disease and ultimately to discover an affordable cure.

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Know Blood Tests During Pregnancy !

Pregnancy Blood Tests:

As part of your antenatal care you’ll be offered several blood tests. Some are offered to all women, and some are only offered if you might be at risk of a particular infection or inherited condition.

All the tests are done to check for anything that may cause a problem during your pregnancy or after the birth, or to check that your baby is healthy, but you don’t have to have them if you don’t want to.

Talk to your midwife or doctor and give yourself enough time to make your decision. They should also give you written information about the tests. Below is an outline of all the tests that can be offered.

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Serum Iron Test: High, Low, and Normal Ranges !

Serum Iron Test

Having too much or too little iron in the blood can cause serious health problems.

If a doctor suspects that a person does not have a healthy amount of iron in their blood, they may order a serum iron test.

In this article, learn more about the uses of a serum iron test. We also explain the normal ranges of iron in the blood and the treatment options for people whose iron levels are too high or too low.

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Evaluation of Diabetic Marker HbA1c and Anemia in the Context of Kidney Disease

Each year, more than 100,000 people in the United States are diagnosed with kidney failure, the final stage of kidney disease.1 The most common cause is diabetes, accounting for nearly 44 percent of new cases. Often, a consequence of kidney disease is anemia. This occurs when kidneys fail to generate enough erythropoietin hormone to trigger adequate red blood cell production. For decades, clinicians have successfully used the hemoglobin A1c (HbA1c or A1C) assay to monitor long-term blood glucose control for patients with chronic diabetes. More recently, researchers have studied the HbA1c assay’s use as a potential diagnostic marker for diabetes complications such as kidney disease.

The HbA1c test measures average plasma glucose—hemoglobin in a red blood cell that was combined with glucose over the previous eight to 12 weeks. The higher the HbA1c value, the greater the risk that the diabetes patient will develop kidney disease, and perhaps, anemia, a common consequence of renal disease. However, a chemically modified derivative of hemoglobin called carbamylated hemoglobin (CHb) can affect the accuracy of the HbA1c test results. Studies have shown that the formation of CHb due to abnormal urea concentration is linked to both the severity and the duration of renal failure. Research findings have inspired conflicting viewpoints on the efficacy of HbA1c test results in the presence of CHb and on the level of CHb it takes to affect results. This article explores the links between diabetes and renal failure. It discusses what research has discovered about the effect of CHb on HbA1c testing. Finally, it shows how testing technology has improved to ensure HbA1c testing accuracy.

Read more: Evaluation of Diabetic Marker HbA1c and Anemia in the Context of Kidney Disease

Source: MedicalLaboratoryObserver

Transfusion-Related Thrombocytopenia In a Chronic Renal Failure Patient

Hemostasis is a process to stop bleeding that requires coordinated activities of vascular, platelet, and plasma factors. Under normal conditions, blood vessel injury will trigger endothelial cells to secrete factors that promote adhesion and activation of platelets. First, platelets bind to von Willebrand’s factor (vWF) secreted by endothelial cells through vWF receptors. Attached platelets then undergo degranulation and release factors such as serotonin, which causes vascular constriction. Activated platelets also release other mediators to attract additional platelets for aggregation at the injured sites.

Read more: Transfusion-Related Thrombocytopenia In a Chronic Renal Failure Patient

Source: MedicalLaboratoryObserver

Point-Of-Care Hemoglobin Testing: Methods And Relevance To Combat Anemia

Anemia is a condition that causes a high degree of personal disability but, historically, has lacked adequate resourcing in many public health systems. This situation is even less understandable when you consider that the main diagnostic, hemoglobin testing, is one of the most commonly used point-of-care (POC) tests, and one of the easiest to perform.

POC hemoglobin testing is often needed in settings where the use of a benchtop laboratory hematology analyzer is not practical. It is ideal for use in settings where resources are poor, or there is a need for mobility and simplicity in field use, or where turnaround time (TAT) for the test result needs to be short, as in acute clinical situations.

Read more: Point-Of-Care Hemoglobin Testing: Methods And Relevance To Combat Anemia

Source: MedicalLaboratoryObserver

Sickle Cell Disease: Nurses Need Better Training, says Health Union

The NHS needs nurses to be better trained in dealing with sickle cell disease, a union has warned.

The Royal College of Nursing described a poor level of awareness and knowledge in accident and emergency units about the potentially fatal disease.

Sickle cell disease (SCD) is the name for a group of inherited conditions that affect the red blood cells - the worst of which is sickle cell anaemia.

Read more:  Sickle Cell Disease: Nurses Need Better Training, says Health Union

Source: bbc.com/news/health

Anemia

Anemia is a condition characterized by an inadequate amount of red blood cells, which are produced in your bone marrow. Red blood cells contain hemoglobin, a substance that picks up oxygen from your lungs, carries it throughout your body, and gives it to your cells. Your cells need oxygen to perform the basic functions that generate energy and keep you alive. In addition, hemoglobin picks up some of the carbon dioxide given off by your cells and returns it to the lungs, where it is exhaled when you breathe out. Without enough red blood cells to transport oxygen to your cells and carbon dioxide away from your cells, your body functions at a less than optimal level.

There are many causes of anemia, which can be broadly grouped into three categories:

Blood Loss

If you are bleeding heavily, you will rapidly become anemic and may develop severe symptoms including shock. Slower leakage of blood that you are unaware of, such as bleeding from a stomach ulcer or from colon cancer , can also exceed your bone marrow’s ability to replace blood supplies, eventually resulting in anemia.

Failure to Make Enough Normal Red Blood Cells or Hemoglobin

Dietary intake of iron, folic acid, and vitamin B 12 are necessary for red blood cell formation. Deficiencies of these nutrients can impair bone marrow function, thus reducing production of adequate numbers of red blood cells. In addition, cancers, certain drugs and toxins, allergic reactions to medicines, and chronic illness can cripple the bone marrow so that it makes defective or insufficient red blood cells. Hereditary defects, such as sickle cell disease , also may lead to anemia. When the bone marrow fails completely the condition is known as aplastic anemia.

Read more: Anemia

Source: Nucleus Medical Media