Anemia in the Elderly Essay Sample
Anemia is a common rising problem with the elderly. The prevalence estimated to 17% in older adults (Stauder). According to the elderly patients table results she is 30g/l below the normal range for Hb, but she is 15fl above the normal range for MCV. These results indicate that the patient may be suffering from macrocytic anemia. Macrocytic anemia is characterised by having a low Hb but a high MCV. Macrocytic anemia can be classified as either megaloblastic or non-megaloblastic. Megaloblastic is caused by the loss of function or deficiency of folate or vitamin B12 in the body. While Non-megaloblastic could be caused by alcoholism, hypothyroidism, myelodysplastic syndrome (MDS), liver dysfunction and others.
Megaloblastic anemia is the most common type of macrocytic anemia. Megaloblastic states are caused by faulty DNA synthesis. Vitamin B12 and folate are needed for purine and thymidylate synthesis. The deficiency of these nutrients affects rapidly dividing cells. However, RNA synthesis still occurs resulting in a big cell with a large nucleus and a nuclear chromatin with an altered appearance. When cytoplasmic maturity exceeds nuclear maturity, dyspoiesis occurs, causing megaloblasts to form in the bone marrow before they reach the peripheral circulation. Because dyspoiesis causes intramedullary cell death, erythropoiesis is rendered inefficient. Dyspoiesis, which affects all cell types, causes reticulocytopenia, leukopenia, and thrombocytopenia. Macro-ovalocytes are released into the circulatory system. Neutrophils that are polymorphonuclear frequently hyper segment. Nucleus fragments are frequently discovered. Overall, megaloblastic anemia develops slowly, and symptoms may not appear until the anemia has progressed to a severe level. Diarrhoea, glossitis, and other gastrointestinal symptoms are prevalent.
Non megaloblastic anemia occurs in a variety of clinical states. Not all of them understood. Here there is no impairment with DNA synthesis. Disorders associated with increased membrane surface area, accelerated erythropoiesis, alcoholism, and chronic obstructive pulmonary disease are all included in this category COPD (Chronic Obstructive Pulmonary Disease). When cholesterol esterification is impaired in patients with chronic liver disease, macrocytosis due to excess red blood cells (RBC) membrane occurs. In the absence of folate deficiency, chronic alcohol use can result in macrocytosis with an MCV of 100 to 105 fL/cell. Mild macrocytosis can occur in aplastic anemia, particularly as the patient recovers. Macrocytosis is a common complication of myelodysplasia because RBC membrane moulding occurs in the spleen following cell release from the marrow. Reticulocytosis (for example, in hemolytic anemia) can result in macrocytosis. Patients with hepatic disease and obstructive jaundice have macrocytosis as a result of increased cholesterol or phospholipid deposition on the membranes of circulating red blood cells (RBCs). Similarly, RBC membrane lipids that are normally removed during splenic maturation are not effectively removed in splenectomised patients, resulting in a larger-than-normal cell. The reticulocyte count rises in patients with hemolytic anemia or posthemorrhagic anemia. The reticulocyte, an immature RBC, is roughly 20% larger than the mature RBC. When a reticulocyte is prematurely released from the bone marrow, its volume is averaged with that of the more mature RBC, and the resulting MCV is increased.
The figure above shows the differential diagnosis of macrocytic anemia
Causes of anemia in the elderly are divided into three broad groups: nutritional deficiency, anemia of chronic disease (ACD) and unexplained anemia (UA). These groups are not, however, mutually exclusive. In any given patient, several causes may co-exist and may each contribute independently to the anemia.
In anaemic individuals with macrocytic indices, megaloblastic anemia is suspected. It should also be examined in individuals who have risk factors and have unexplained paresthesias and/or a wide RBC distribution width (RDW). A peripheral smear is frequently used to get a diagnosis. In the absence of iron shortage, thalassemia trait, or renal illness, the anemia is macrocytic, with MCV > 100 fL/cell when completely grown. The smear reveals macro-ovalocytosis, anisocytosis (RBC size fluctuation), and poikilocytosis (variation in RBC shape).
The RDW is quite high. The Howell-Jolly body type is prevalent. There is reticulocytopenia. Granulocyte hypersegmentation appears first, followed by neutropenia. Thrombocytopenia is common in severe instances, and platelets might be oddly shaped and sized. Even though anemia can disguise macrocytosis, Howell-Jolly bodies and granulocyte hypersegmentation should still be evident.
The levels of B12 and folate in the blood should be checked. Deficiency is usually diagnosed by a B12 level of 200 pg/mL (147.6 pmol/L) or a folate level of 2 ng/mL (4.453 nmol/L). Nondiagnostic B12 levels range from 200 to 300 pg/mL (147.6 to 221.3 pmol/L). Neurologic signs, such as peripheral neuropathy and gait instability, are peculiar to B12 insufficiency and, if untreated, can be permanent. Even before (or in the absence of) anemia, paresthesias might be the presenting symptom of B12 insufficiency.
When vitamin B12 levels are insufficient, methylmalonic acid (MMA) and homocysteine (HCY) levels should be measured. In B12 insufficiency, serum levels of both MMA and HCY are high, whereas only HCY is raised in folate deficit. Renal failure raises the MMA level. It is also necessary to do an evaluation to discover the reason of the vitamin deficit.
A reticulocyte count should be obtained once vitamin B12, or folate deficiency has been ruled out. Reticulocytes are nonnucleated erythrocytes that are immature. In general, reticulocytes account for about 1% of all red blood cells. Acute blood loss or hemolysis is suspected if the absolute reticulocyte count exceeds 100 000/l. High levels of indirect bilirubin and LDH, as well as low levels of haptoglobin, indicate hemolytic anemia. If hemolysis is not present, acute blood loss should be considered as a possibility. The lack of reticulocytosis suggests alcoholism, liver dysfunction, hypothyroidism, or MDS. In liver disease, macrocytic target cells are commonly seen on peripheral blood smears, as are hypolobulated or hypogranular neutrophils, large and/or abnormally granulated platelets, and monocytosis.
The MCV values may be falsely elevated when significant reticulocytosis is present, or when there is an abnormally elevated level of hyperglycemia. Extremely high MCV (>130 fL) narrows the differential diagnosis, to include ART treatment for HIV infection, use of hydroxyurea, and vitamin B12 or folate deficiency.
Treatment is based on supplementing the patient with the deficient vitamins through vitamin tablets or injections. Drugs that can induce megaloblastic states are reduced or eliminated. The etiology of the vitamin deficiency is treated too. E.g., macrocytic anemia caused by alcoholism would have to be treated with the non- consumption of alcohol and the uptake of vital vitamins. In some cases, a bone marrow examination is needed for patients who do not respond to treatments.
