Pathophysiology Final Exam 1 Study guide Latest Updated 2023, Exams of Nursing

Download Pathophysiology Final Exam 1 Study guide Latest Updated 2023 and more Exams Nursing in PDF only on Docsity! Pathophysiology Final Exam 1 Study guide Latest Updated 2023 CHAPTER 1 Pathophysiology the study of functional or physiologic changes in the body that result from disease processes. Characteristics of disease- review all • Pathogenesis refers to the development of the disease or the sequence of events involved in the tissue changes related to the specific disease process. • The onset of a disease may be sudden and obvious or acute; for example, gastroenteritis with vomiting, cramps, and diarrhea; or the onset may be insidious, best described as a gradual progression with only vague or very mild signs. Hepatitis may manifest quietly in this way. There may be several stages in the development of a single disease. • An acute disease indicates a short-term illness that develops very quickly with marked signs such as high fever or severe pain; for example, acute appendicitis. • A chronic disease is often a milder condition developing gradually, such as rheumatoid arthritis, but it persists for a long time and usually causes more permanent tissue damage. Often a chronic disease is marked by intermittent acute episodes. • A subclinical state exists in some conditions in which pathologic changes occur, but no obvious manifestations are exhibited by the patient, perhaps because of the great reserve capacity of some organs. For example, kidney damage may progress to an advanced stage of renal failure before symptoms are manifested. • An initial latent or “silent” stage, in which no clinical signs are evident, characterizes some diseases. In infectious diseases this stage may be referred to as the incubation period, which is the time between exposure to the microorganism and the onset of signs or symptoms; it may last for a day or so or may be prolonged, perhaps for days or weeks. Often the disease agent may be communicable during this incubation period. •The prodromal period comprises the time in the early development of a disease when one is aware of a change in the body, but the signs are nonspecific; for example, fatigue, loss of appetite, or headache. A sense of feeling threatened often develops in the early stage of infections. Laboratory tests are negative during the prodromal period; thus it is difficult to confirm a diagnosis. •The manifestations of a disease are the clinical evidence or effects, the signs and symptoms, of disease. These manifestations, such as redness and swelling, may be local, or found at the site of the problem. Or signs and symptoms may be systemic, meaning they are general indicators of illness, such as fever. • Signs are objective indicators of disease that are obvious to someone other than the affected individual. Examples of a sign are a fever or a skin rash. • Symptoms are subjective feelings, such as pain or nausea. Both signs and symptoms are Pathophysiology Final Exam 1 Study guide Latest Updated 2023 significant in diagnosing a particular problem. Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Disease Prevention- (Primary prevention examples) Primary Prevention The goal is to protect healthy people from developing a disease or experiencing an injury in the first place. For example: •Education about good nutrition, the importance of regular exercise, and the dangers of tobacco, alcohol, and other drugs •Education and legislation about proper seatbelt and helmet use •Regular exams and screening tests to monitor risk factors for illness •Immunization against infectious disease •Controlling potential hazards at home and in the workplace Secondary Prevention These interventions happen after an illness or serious risk factors have already been diagnosed. The goal is to halt or slow the progress of disease (if possible) in its earliest stages; in the case of injury, goals include limiting long-term disability and preventing re-injury. For example: •Telling people to take daily, low-dose aspirin to prevent a first or second heart attack or stroke •Recommending regular exams and screening tests in people with known risk factors for illness •Providing suitably modified work for injured workers Tertiary Prevention This focuses on helping people manage complicated, long-term health problems such as diabetes, heart disease, cancer, and chronic musculoskeletal pain. The goals include preventing further physical deterioration and maximizing quality of life. For example: •Cardiac or stroke rehabilitation programs •Chronic pain management programs •Patient support groups Some terms to thoroughly review Hypertrophy increased size of an organ or muscle due to increased size of individual cells. Atrophy degeneration and wasting of tissue, organs, or muscle due to Pathophysiology Final Exam 1 Study guide Latest Updated 2023 decrease in cell size. Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Dysplasia disorganized cells that vary in size and shape with large nuclei. Apoptosis normal programmed cell death in tissues. CHAPTER 2 Insensible fluid loss Fluid is lost in the urine and feces as well as through insensible (unapparent) losses through the skin (perspiration) and exhaled air. Causes of edema 1. The first cause is increased capillary hydrostatic pressure (equivalent to higher BP or blood pressure), which prevents return of fluid from the interstitial compartment to the venous end of the capillary, or forces excessive amounts of fluid out of the capillaries into the tissues. The latter is a cause of pulmonary edema, in which excessive pressure, often due to increased blood volume, can force fluid into the alveoli, interfering with respiratory function.Specific causes of edema related to increased hydrostatic pressure include increased blood volume (hypervolemia) associated with kidney failure, pregnancy, congestive heart failure, or administration of excessive fluids. In pregnancy, the enlarged uterus compresses the pelvic veins in the seated position and when a pregnant woman must stand still for long periods of time, the pressure in the leg veins can become quite elevated, causing edema in the feet and legs. In some people with congestive heart failure, the blood cannot return easily through the veins to the heart, raising the hydrostatic pressure in the legs and abdominal organs and causing ascites, or fluid in the abdominal cavity. 2. Second, edema may be related to the loss of plasma proteins, particularly albumin, which results in a decrease in plasma osmotic pressure. Plasma proteins usually remain inside the capillary and seldom move through the semipermeable capillary membrane. The presence of fewer plasma proteins in the capillary allows more fluid to leave the capillary and less fluid to return to the venous end of the capillary.Protein may be lost in the urine through kidney disease, or synthesis of protein may be impaired in patients with malnutrition and malabsorption diseases or with liver disease. Protein levels may drop acutely in burn patients who have large areas of burned skin; the subsequent inflammation and loss of the skin barrier allow protein to easily leak out of the body.Frequently excessive sodium levels in the extracellular fluid accompany the two causes just mentioned. When sodium ions are retained, they promote accumulation of fluid in the interstitial compartment by increasing the ISF osmotic pressure and decreasing the return of fluid to the blood. Blood volume and blood pressure are usually elevated as well. High sodium levels are common in patients with heart failure, high blood pressure, kidney disease, and increased aldosterone secretion. 3. Edema may result from obstruction of the lymphatic circulation. Such an obstruction usually causes a localized edema because excessive fluid and protein are not returned to the general circulation. This situation may develop if a tumor or infection damages a lymph node or if lymph Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Causes of Hyponatremia Pathophysiology Final Exam 1 Study guide Latest Updated 2023 A sodium deficit can result from direct loss of sodium from the body or from an excess of water in the extracellular compartment, resulting in dilution of sodium. Common causes of low serum sodium levels include: 1. Losses from excessive sweating, vomiting, and diarrhea 2. Use of certain diuretic drugs combined with low-salt diets 3. Hormonal imbalances such as insufficient aldosterone, adrenal insufficiency, and excess ADH secretion 4. Early chronic renal failure 5. Excessive water intake Effects of Hyponatremia • Low sodium levels impair nerve conduction and result in fluid imbalances in the compartments. Manifestations include fatigue, muscle cramps, and abdominal discomfort or cramps with nausea and vomiting. • Decreased osmotic pressure in the extracellular compartment may cause a fluid shift into cells, resulting in hypovolemia and decreased blood pressure. • The brain cells may swell, causing confusion, headache, weakness, or seizures. Hypernatremia Hypernatremia is an excessive sodium level in the blood and extracellular fluids (more than 145 mEq per liter). Causes of Hypernatremia Excess sodium results from ingestion of large amounts of sodium without proportionate water intake or a loss of water from the body that is faster than the loss of sodium. Specific causes include: 1.Insufficient ADH, which results in a large volume of dilute urine (diabetes insipidus) 2.Loss of the thirst mechanism 3. Watery diarrhea 4. Prolonged periods of rapid respiration Effects of Hypernatremia The major effect of hypernatremia is a fluid shift out of the cells owing to the increased osmotic pressure of interstitial or extracellular fluid; this effect is manifested by: •Weakness, agitation •Firm subcutaneous tissues Pathophysiology Final Exam 1 Study guide Latest Updated 2023 •Increased thirst, with dry, rough mucous membranes Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Type of chromosomal disorder Down syndrome is an example of a trisomy, in which there are three chromosomes rather than two in the 21 position; it is called trisomy 21 (see Fig. 21-1C). Therefore an individual with Down syndrome has 47 chromosomes. A less common form of Down syndrome exists in which part of a chromosome 21 is attached to another chromosome (translocation). Trisomy 21 change has marked effects throughout the body. Additional information is provided at the end of the chapter. Monosomy X, or Turner syndrome (Fig. 21-6), occurs when only one sex chromosome, the X chromosome, is present. This person has only 45 chromosomes, resulting in a variety of physical abnormalities and lack of ovaries. In Klinefelter's syndrome polysomy X, an extra X chromosome is present (XXY), resulting in a total of 47 chromosomes in each cell. Not all males show signs and are diagnosed, but typically, testes are small and sperm are not produced. Other common chromosomal abnormalities occur when parts of chromosomes are rearranged or lost during replication. Common manifestations Causes of developmental disorders Exposure to negative environmental influences during pregnancy and even before pregnancy such as radiation may cause changes in the sperm or ova. Evidence has been gathered about the damaging effects on the fetus of alcohol (fetal alcohol syndrome), cigarette smoking (low birthweight and increased risk of stillbirth), radiation, pharmaceuticals, cocaine abuse, and maternal infections. Chemicals such as mercury in food and water, as well as many drugs, can cross the placental barrier and damage the rapidly dividing cells of the embryo and fetus. TORCH is an acronym applied to routine prenatal screening tests for high-risk maternal infections: Toxoplasmosis, Other (hepatitis B, mumps, rubeola, varicella, gonorrhea, syphilis), Rubella, Cytomegalovirus, and Herpes. Newer programs provide integrated assessment of the TORCH diseases as well as other significant teratogenic or harmful factors. Because many chemicals and drugs are thought to be possibly teratogenic, and because it is difficult to establish proof of such harm, it is recommended that women avoid unnecessary exposure to drugs, chemicals, or radiation during the childbearing years. In most cases, the damage to the embryo occurs in the early period before a pregnancy is suspected. A deficit or excess of particular nutrients can also lead to developmental abnormalities. The cause of specific malformations is rarely known. Exposure to harmful influences in the first 2 weeks of embryonic life usually results in the death of the embryo. The most critical time is the first 2 months of development, when the cells are dividing rapidly and differentiating, organogenesis is taking place, and the basic body structures are forming (Fig. 21-9). Changes in the basic cells at this time have far-reaching effects. The effects of exposure depend on the stage of development at the precise time of the exposure. In addition to an anomaly, or a developmental abnormality, exposure to damaging substances such as cocaine may cause premature birth, a high risk of further illness in the infant (low birthweight Pathophysiology Final Exam 1 Study guide Latest Updated 2023 or increased respiratory problems), and increased risk of sudden infant death syndrome. Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Cerebral palsy is an example of the kind of brain damage that can occur before, during, or immediately after birth (see Chapter 14). The cause may be insufficient oxygen, the toxic effects of excessive bilirubin in the blood (jaundice), or trauma. The effects may be localized or may involve several areas of the brain. Impact of exposure to harmful/damaging substances In addition to an anomaly, or a developmental abnormality, exposure to damaging substances such as cocaine may cause premature birth, a high risk of further illness in the infant (low birth weight or increased respiratory problems), and increased risk of sudden infant death syndrome. Mutation a change in the genetic makeup (DNA) of a cell, which will be inherited. Meiosis is a type of cell division that reduces the number of chromosomes in the parent cell by half and produces four gamete cells. This process is required to produce egg and sperm cells for sexual reproduction. Mitosis a process of cell reproduction resulting in two daughter cells with the same DNA as the parent cell. CHAPTER 5 Inflammatory response pathophysiology and manifestations The inflammatory response is a protective mechanism and an important basic concept in pathophysiology. Inflammation is a normal defense mechanism in the body and is intended to localize and remove an injurious agent, whatever it may be. You have probably observed the inflammatory process resulting from a cut, an allergic reaction, an insect bite, an infection, or a small burn on your body. The general signs and symptoms of inflammation serve as a warning of a problem, which may be hidden within the body. Inflammation is not the same as infection, although infection is one cause of inflammation. With infection, microorganisms such as a bacteria, viruses, or fungi are always present at the site, causing the inflammation. This microbe can be identified and appropriate treatment instituted to reduce the infection, and the inflammation will subside. When inflammation is caused by an allergy or a burn, no microbes are present. Pathophysiology Final Exam 1 Study guide Latest Updated 2023 material at the site, while the globulins serve as antibodies, and fibrinogen forms a fibrin mesh around the area in an attempt to localize the injurious agent. Any blood clotting will also provide Pathophysiology Final Exam 1 Study guide Latest Updated 2023 a fibrin mesh to wall off the area. Vasodilation and increased capillary permeability make up the vascular response to injury. During the cellular response, leukocytes are attracted by chemotaxis to the area of inflammation as damaged cells release their contents. Several chemical mediators at the site of injury act as potent stimuli to attract leukocytes. Leukocytes and their functions are summarized in Table 5-2. First neutrophils (polymorphonuclear Local Effects The cardinal signs of inflammation are redness (rubor or erythema), heat, swelling, and pain: •Redness and warmth are caused by increased blood flow into the damaged area (Fig. 5-3) •Swelling or edema is caused by the shift of protein and fluid into the interstitial space. •Pain results from the increased pressure of fluid on the nerves, especially in enclosed areas, and by the local irritation of nerves by chemical mediators such as bradykinins. •Loss of function may develop if the cells lack nutrients or swelling interferes mechanically with function, as happens in restricted joint movement. Exudate refers to a collection of interstitial fluid formed in the inflamed area. The characteristics of the exudate vary with the cause of the trauma: • Serous or watery exudates consist primarily of fluid with small amounts of protein and white blood cells. Common examples of serous exudates occur with allergic reactions or burns. •Fibrinous exudates are thick and sticky and have a high cell and fibrin content. This type of exudate increases the risk of scar tissue in the area. • Purulent exudates are thick, yellow-green in color, and contain more leukocytes and cell debris as well as microorganisms. Typically, this type of exudate indicates bacterial infection, and the exudate is often referred to as “pus.” • An abscess is a localized pocket of purulent exudate or pus in a solid tissue (e.g., around a tooth or in the brain). •A hemorrhagic exudate may be present if blood vessels have been damaged. Systemic Effects Other general manifestations of inflammation include mild fever, malaise (feeling unwell), fatigue, headache, and anorexia (loss of appetite). Fever or pyrexia (low grade or mild) is common if inflammation is extensive. If infection has caused the inflammation, fever can be severe, depending on the particular microorganism. However, high fever can be beneficial if it impairs the growth and reproduction of a pathogenic organism. Fever results from the release of pyrogens, or fever-producing substances (e.g., interleukin-1), from white blood cells (WBCs) or macrophages (Fig. 5-4). Pyrogens circulate in the blood and cause the body temperature control system (the thermostat) in the hypothalamus to be reset at a higher level. Heat production mechanisms such as shivering are activated to increase cell metabolism. Involuntary cutaneous vasoconstriction characterized by pallor and cool skin reduces heat loss from the body. Voluntary actions such as curling up or covering the body conserve heat. These mechanisms continue until the body temperature reaches the new, higher setting. Following removal of the cause, body temperature returns to normal by reversing the mechanisms. Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Chemical mediators and examples Burns and classification of burns A burn is a thermal (heat) or nonthermal (electrical or chemical) injury to the body, causing acute inflammation and tissue destruction. Burns may be mild or cover only a small area of the body, or they may be severe and life threatening, as when an extensive area is involved. Burns may be caused by direct contact with a heat source such as flames or hot water (a scald), by chemicals, radiation, electricity, light, or friction. Most burns occur in the home. Any burn injury causes an acute inflammatory response and release of chemical mediators, resulting in a major fluid shift, edema, and decreased blood volume. Major burns constitute a medical emergency requiring specialized care as quickly as possible. The severity of the burn depends on the cause of the burn, and the temperature, duration of the contact, as well as the extent of the burn surface and the site of the injury. Young children with their thin skin frequently receive severe burns from immersion in excessively hot water in a bathtub. The elderly also have thinner skin; therefore they can suffer much deeper burn injuries than younger adults. Skin thickness varies over the body, with facial skin being much thinner than the skin on the palms and soles. Thus, facial burns are more often more damaging than burns to the soles of the feet. Classifications of Burns Burns are classified by the depth of skin damage and the percentage of body surface area involved. Partial-thickness burns involve the epidermis and part of the dermis (Fig. 5-10). Superficial partial-thickness burns (formerly known as first-degree burns) damage the epidermis and may involve the upper dermis. They usually appear red and painful but heal readily without scar tissue. Examples include sunburn or a mild scald. Deep partial-thickness burns (formerly second-degree burns) involve the destruction of the epidermis and part of the dermis (Fig. 5-11). The area is red, edematous, blistered, and often hypersensitive and painful during the inflammatory stage. In severe cases, the skin appears waxy with a reddened margin. The dead skin gradually sloughs off, and healing occurs by regeneration from the edges of the blistered areas and from epithelium lining the hair follicles and glands. If the area is extensive, healing may be difficult, and complications occur. Grafts may be necessary to cover larger areas. These burns easily become infected, causing additional tissue destruction and scar tissue formation. Full-thickness burns (formerly third- and fourth-degree burns) result in destruction of all skin layers and often underlying tissues as well (see Fig. 5-11C). The burn wound area is coagulated or charred and therefore is hard and dry on the surface. This damaged tissue (eschar) shrinks, causing pressure on the edematous tissue beneath it. If the entire circumference of a limb is involved, treatment (escharotomy—surgical cuts through this crust) may be necessary to release the pressure and allow better circulation to the area. This procedure may also be required when a large area of the chest is covered by eschar, impairing lung expansion. Initially the burn area may Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Genomics is the basis for several new types of antiviral drugs as the search continues for drugs targeting Hepatitis B and/or C, enteroviruses, HIV, and other viral pathogens. One type of drug is Pathophysiology Final Exam 1 Study guide Latest Updated 2023 based on blocking segments of viral DNA or RNA with antisense molecules, rendering the nucleic acid incapable of expression or replication. Ribozymes are enzymes that split DNA or RNA into segments and inhibit replication of viral genes in the cell. These new agents appear to be active against several types of viruses; a few drugs are in clinical trials. Transmission of infectious agents – direct and indirect contact A chain of events occurs during the transmission of infecting organisms from one person to another (Fig. 6-11). The reservoir, or source of infection, may be a person with an obvious active infection in an acute stage, or a person who is asymptomatic and shows no clinical signs or symptoms. The latter may be in the early incubation stage of infection, or the person may be a carrier of the organism and never develop infection. Hepatitis B is an example of an infection that is often transmitted by unknown carriers or persons who have a subclinical form of infection that is very mild, with few or no manifestations. The reservoir also may be an animal or contaminated water, soil, food, or equipment. • Direct contact with no intermediary, such as touching an infectious lesion or sexual intercourse. Microbes may be in the blood, body secretions, or a lesion. Not all microorganisms can cross the blood-brain barrier or placental barriers. However, some microbes that can cross the placenta have serious effects on fetal development and health. Treponema pallidum, the cause of syphilis, can lead to multiple defects or death in the fetus, and Toxoplasma gondii, the cause of toxoplasmosis, results in many neurologic deficits. •Indirect contact involving an intermediary such as a contaminated hand or food, or a fomite, an inanimate object such as instruments or bed linen that carries organisms. In some cases, there are several stages in transmission. For example, shellfish can be contaminated by human feces in the water. The microorganisms in the shellfish are then ingested and cause infection in another human. • Droplet transmission (oral or respiratory) occurring when respiratory or salivary secretions containing pathogens such as tuberculosis bacteria are expelled from the body. The organisms from these secretions may be inhaled directly by another person close by or fall on nearby objects to be transmitted indirectly. • Aerosol transmission involving small particles from the respiratory tract that remain suspended in the air and travel on air currents, infecting any new host who inhales the particles. •Vector-borne, when an insect or animal serves as an intermediary host in a disease such as malaria. Local and systemic signs of infection The local signs of infection are usually those of inflammation: pain or tenderness, swelling, redness, and warmth (Fig. 6-14). If the infection is caused by bacteria, a purulent exudate, or pus, is usually present, whereas a viral infection results in serous, clear exudates. The color and other characteristics of the exudates and tissue may help to identify the microorganism. Figure 5- 13 illustrates infection of a burn wound by two different microorganisms. Tissue necrosis at the Pathophysiology Final Exam 1 Study guide Latest Updated 2023 site is likely as well. Lymphadenopathy occurs and is manifest by swollen and tender lymph nodes (Table 6-4). Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Type1 Example Mechanism Effects Hay fever; anaphylaxis IgE bound to mast cells; release of histamine andchemical mediators Immediate inflammation and pruritus Anaphylaxis pathophysiology and causes Anaphylaxis or Anaphylactic Shock Anaphylaxis is a severe, life-threatening, systemic hypersensitivity reaction resulting in decreased blood pressure, airway obstruction, and severe hypoxia. Commonly caused by exposure to latex materials such as gloves, insect stings, ingestion of nuts or shellfish, administration of penicillin, or local anesthetic injections, the reaction usually occurs within minutes of the exposure. Pathophysiology Large amounts of chemical mediators are released from mast cells into the general circulation very quickly, resulting in two serious problems. General or systemic vasodilation occurs with a sudden, severe decrease in blood pressure. In the lungs, edema of the mucosa and constriction of the bronchi and bronchioles occur, obstructing airflow (Fig. 7-5). The marked lack of oxygen that results from both respiratory and circulatory impairment causes loss of consciousness within minutes. Autoimmune disease definition and examples Autoimmune disorders occur when the immune system cannot distinguish between self and non– self-antigens. The exact causes of autoimmune diseases/disorders are still unknown. Autoimmune disorders occur when individuals develop antibodies to their own cells or cellular material and these antibodies then attack the individual's tissues (Fig. 7-9). The term autoantibodies refers to antibodies formed against self-antigens. There is greater recognition as well as better diagnosis and treatment of autoimmune disorders now due to advances in diagnostic procedures. Some of these disorders affect single organs or tissues, for example, Hashimoto's thyroiditis, and some are generalized, such as systemic lupus erythematosus. Other examples are rheumatic fever, myasthenia gravis, scleroderma, pernicious anemia, and hyper- thyroidism (Graves' disease). Self-antigens are usually tolerated by the immune system, and there is no reaction to one's own antigens. When self-tolerance is lost, the immune system is unable to differentiate self from foreign material. The autoantibodies then trigger an immune reaction leading to inflammation and necrosis of tissue. Some individuals may lose their immune tolerance following tissue Pathophysiology Final Exam 1 Study guide Latest Updated 2023 destruction and subsequent formation of antibodies to the damaged cell components. Aging may Pathophysiology Final Exam 1 Study guide Latest Updated 2023 lead to loss of tolerance to self-antigens. There also appears to be a genetic factor involved in autoimmune diseases, as evidenced by increased familial incidence. Example: Systemic Lupus Erythematosus Systemic lupus erythematosus pathophysiology and causes Systemic lupus erythematosus (SLE) is a chronic inflammatory disease that affects a number of systems; therefore it can be difficult to diagnose and treat. The name of this systemic disorder is derived from the characteristic facial rash, which is erythematous and occurs across the nose and cheeks, resembling the markings of a wolf (lupus) (Fig. 7-10). The rash is now often referred to as a “butterfly rash,” reflecting its distribution. The condition is becoming better known and more cases are identified in the early stages, improving the prognosis. Certain drugs may cause a lupus-like syndrome, which usually disappears when the drug is discontinued. Discoid lupus erythematosus is a less serious version of the disease affecting only the skin. Occurrence is uncertain because many cases are probably not diagnosed in the early stages. Systemic lupus erythematosus affects primarily women and becomes manifest between the ages of 20 and 40 years. The incidence is higher in African Americans, Asians, Hispanics, and Native Americans. The specific cause has not been established, but it appears to be multifactorial and includes genetic, hormonal (estrogen levels), and environmental (ultraviolet light exposure) factors. A single lupus gene has not been identified, but genes increasing susceptibility to autoimmune disorders have been identified. A number of research projects are in process, including studies of the complement system and immune systems in affected individuals and their families. Another focus concerns identification of a possible genetic defect interfering with normal apoptosis and removal of damaged cells, leaving cell contents such as nucleic acids in the tissues. Pathophysiology Systemic lupus erythematosus is characterized by the presence of large numbers of circulating autoantibodies against DNA, platelets, erythrocytes, various nucleic acids, and other nuclear materials (antinuclear antibodies [ANAs]). Immune complexes, especially those with anti-DNA antibody, are deposited in connective tissues anywhere in the body, activating complement and causing inflammation and necrosis. Vasculitis, or inflammation of the blood vessels, develops in many organs, impairing blood supply to the tissue. The resulting ischemia (inadequate oxygen for the cells) leads to further inflammation and destruction of the tissue. This process usually takes place in several organs or tissues. Common sites include the kidneys, lungs, heart, brain, skin, joints, and digestive tract. Diagnosis is based on the presence of multiple system involvement (a minimum of four areas) and laboratory data showing the presence of autoantibodies. HIV pathophysiology and transmission Acquired immunodeficiency syndrome (AIDS) is a chronic infectious disease caused by HIV, which destroys helper T-lymphocytes, causing loss of the immune response and increased susceptibility to secondary infections and cancer. It is characterized by a prolonged latent period Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Characteristics of specific tumors vary considerably depending on the cell of origin. The general characteristics of each type are summarized in Table 20-2. Benign tumors usually consist of differentiated cells that reproduce at a higher than normal rate. The benign tumor is often encapsulated and expands but does not spread (Fig. 20-1). It is usually freely moveable on palpation. Tissue damage results from compression of adjacent structures such as blood vessels. A benign tumor is not considered life threatening unless it is in an area such as the brain where the pressure effects can become critical. By comparison, malignant tumors are usually made up of undifferentiated, nonfunctional cells that do not appear organized. The cells tend to reproduce more rapidly than normal and often show abnormal mitotic figures. These cells have lost cellular connections with each other, and reproduction is not inhibited in the presence of other similar cells. Tumor cells infiltrate or spread into surrounding tissue and may easily metastasize or break away to spread to other organs and tissues (Fig. 20-2). Benign Tumors Malignant Tumors Cells Growth Similar to normal cells Varied in size and shape with large nuclei Differentiated Many undifferentiated Mitosis fairly normal Mitosis increased and atypical Relatively slow Rapid growth Expanding mass Cells not adhesive, infiltrate tissue Frequently encapsulated No capsule Spread Remains localized Invades nearby tissues or metastasizes to distant sites through bloo and lymph vessels Systemic effects Life- threatening Rare Often present Only in certain locations (e.g., Yes, by tissue destruction and spread of tumors brain) Warning signs of cancer 1. Unusual bleeding or discharge anywhere in the body. 2. Change in bowel or bladder habits (e.g., prolonged diarrhea or discomfort). 3. A change in a wart or mole (i.e., color, size, or shape). 4. A sore that does not heal (on the skin or in the mouth, anywhere). 5. Unexplained weight loss. 6. Anemia or low hemoglobin, and persistent fatigue. 7. Persistent cough or hoarseness without reason. 8. A solid lump, often painless, in the breast or testes or anywhere on the body. Metastasis Pathophysiology Final Exam 1 Study guide Latest Updated 2023 means spread to distant sites by blood or lymphatic channels. In this case the tumor cells erode into a vein or lymphatic vessel, travel through the body, and eventually lodge in a hospitable environment to reproduce and create one or more secondary tumors Serious adverse effects of chemotherapy and radiation therapy Adverse effects (side effects) may be quite marked with drug therapy. As with radiation, the normal cells are also damaged, most commonly the skin and mucosa, bone marrow, and gonads. The need to minimize adverse effects is another factor in choosing the combination. For example, not all the drugs in a combination can seriously depress the bone marrow, but rather, one of the drugs in the combination may cause nausea or hair loss. •Bone marrow depression is the limiting factor with chemotherapy, and dangerously low blood counts may require transfusions or cessation of therapy until the bone marrow recovers. Blood tests are taken before each treatment to check cell count. The nadir, or point of lowest cell count (neutropenia or leukopenia), may occur at different points in the cycle depending on the particular drug. If the count is too low, treatment may need to be postponed, and antibiotics or hospitalization may be required. Hemorrhage is a major risk with thrombocytopenia. Infections are common with neutropenia, septicemia with tumors in the gastrointestinal tract, and pneumonia with lung cancers. Skin infections are common, particularly if immobility or malnutrition has led to skin breakdown. Of course, in cases in which the blood cells are already reduced in number or function, as with the leukemias, the effects of chemotherapy can be critical. •Vomiting may occur during or shortly after treatment owing to direct chemical stimulation by the drug of the emetic or vomiting center in the brain. Vomiting may continue after treatment in response to the mucosal inflammation and damage in the digestive tract. In some cases, nausea and vomiting develop before chemotherapy administration related to anxiety or past experience. Antiemetic drugs such as ondansetron (Zofran) may be helpful in decreasing vomiting. Alternatives include dexamethasone (Decadron) and prochlorperazine (Stemetil). •Epithelial cells are easily damaged because of the ongoing mitosis. Hair loss (alopecia) and breakdown of skin and mucosa occur frequently. Stomatitis in the mouth and diarrhea are common problems and contribute to malnutrition. Candidal infections are common in the mouth. •In addition, some antineoplastic drugs have unique damaging effects in specific areas; for example, fibrosis in the lungs or damage to myocardial cells. Adverse effects of radiation depend on the dose and extent of penetration of radiation into the body. Normal cells that rapidly reproduce, such as those in the skin and mucosa (epithelial cells), bone marrow, and gonads are also damaged by radiation. 1. Bone marrow depression is the most serious negative effect, so blood cell counts are constantly monitored. Decreased leukocytes greatly increase the risk of infection, decreased platelets may cause excessive bleeding, and decreased erythrocytes contribute to fatigue and tissue breakdown. If blood cell counts are reduced to a critical level, treatment may need to be postponed or blood Pathophysiology Final Exam 1 Study guide Latest Updated 2023 transfusions may be necessary. Pneumonia and septicemia are common life-threatening complications because body defenses are reduced. Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Cancer remission “cure” for cancer is generally defined as a 5-year survival without recurrence after diagnosis and treatment. In some cases, several periods of remission (no clinical signs) may occur before the disease becomes terminal. In some cases, early diagnosis and treatment limit the extent of the illness in an individual. In other cases, cancer treatment involves a prolonged period of illness with intermittent acute episodes. Information and support for the patient and family are offered by the American Cancer Society as well as cancer clinics and the many other community support groups. The death rates for specific cancers vary. For some types of cancer, such as lung cancer, there has been no significant improvement in the outcome even with aggressive treatment. For other cancers, such as certain childhood leukemias and Hodgkin's lymphoma, effective treatment has been developed, and survival rates are much improved. Current statistics for specific cancers are available from the American Cancer Society or Canadian Cancer Society. Prognosis in a specific individual is influenced by many factors and so is subject to change. Cancer risk factors Risk Factors (Carcinogen) Example Breast cancer: high family incidence; Genetic Factors: Oncogenes that regulate all growth retinoblastoma: inherited Leukemia: chromosomal abnormalities Viruses: Oncogenic viruses alter host cell DNA Hepatic cancer: hepatitis virus Cervical cancer: papilloma virus (HPV or herpes simplex II; Kaposi's sarcoma HIV Radiation: Ultraviolet rays (sun), x-rays, gamma rays, and radioactive chemicals cause cumulative chromosomal damage in cells Chemicals: Exposure to both natural and synthetic products in excess may be hazardous; the effects of carcinogenic agents depend on the amount and duration of exposure Skin cancer: sun exposure Leukemia: radiation exposure Lung cancer: asbestos, nickel Leukemia: solvents (e.g., benzene) Bladder cancer: aniline dyes and rubbe Biologic Factors: Chronic irritation and inflammation with increased mitosis Colon cancer: ulcerative colitis; oral cancer: leukoplakia Age: increasing Many cancers are more common in old persons Pathophysiology Final Exam 1 Study guide Latest Updated 2023 Risk Factors (Carcinogen) Example Diet: natural substances, additives, or processing methods Colon cancer: high-fat diet; gastric cancer: smoked foods Diet: natural substances, additives, or processing methods Colon cancer: high-fat diet; gastric cancer: smoked foods Hormones Endometrial cancer: estrogen