If immature B cells encounter antigens to which they bind while still in the bone marrow, a series of events is triggered to induce self-tolerance. Serous exudate is watery and low in protein; ibrinous exudate is thick, sticky, and high in protein; purulent exudate contains infective organisms, leukocytes, and cellular debris; and hemorrhagic exudate contains red blood cells. Tissues also maintain less-differentiated stem cells that are able to proliferate depending on environmental cues. Chest wall compliance, vital capacity, total lung capacity, and expiratory reserve volume are all decreased. The chest radiograph shows depression of the hemidiaphragm on the side of the pneumothorax and a pleural line with absence of vessel markings peripheral to this line. According to the American Society for Apheresis, this type of therapy has been effective in the management of diseases such as myasthenia gravis, thrombocytopenia purpura, multiple sclerosis, and Rh-negative hemolytic disease of the newborn. Platelet aggregation is the problem in thrombasthenia, owing to the absence of the ibrinogen receptor necessary for normal platelet aggregation. This function is accomplished by the movement of O2 from the atmosphere through the airways to alveolar sacs. A variety of drugs can mimic or block the effects of both sympathetic and parasympathetic systems and therefore inluence heart rate (see Chapter 18). This pulmonary embolism may be asymptomatic or present with various signs and symptoms, many of which are vague and nonspeciic. Lymphatic low is therefore enhanced by increased physical activity, increased blood pressure, or increased respiratory rate. Hydrogen ions secreted in to the renal tubular lumen combine with iltered bicarbonate (which then is reabsorbed), buffers (phosphate buffer illustrated here), or ammonia (forming ammonium ions). In the case of prolonged bed rest, active range-of-motion exercises as well as prophylactic low-dose subcutaneous sodium heparin or low-molecular-weight heparins may be used. Because acute inlammation can cause severe tissue damage, it is not surprising that a system of inactivators is present. There are several types of albinism; all types involve disruption of melanin synthesis. Patients who have chronic end-stage renal disease often undergo potassium adaptation and have relatively mild symptoms at high plasma potassium concentrations that would be disabling in other persons. The diagnostic indings in both acute and subacute infective endocarditis are much the same. Consequently, increased production of ammonia is an effective way of excreting more hydrogen ions in the renal tubular luid without making the urine too acidic. Thus, the critical factors in meeting cellular demands for oxygen are (1) the rate of coronary perfusion and (2) the myocardial workload. In managing the anemia related to vitamin B12 or folate deiciency, it is important to (1) recognize that megaloblastic anemia is present; (2) ascertain if vitamin B12, folate, or a combined deiciency is the cause; and (3) diagnose the underlying disease and mechanism responsible for the deiciency. Patients who receive concentrated tube feedings without enough water, especially older adults, are at high risk for hypernatremia because they gain relatively more solute than water, which causes an obligatory loss of relatively more water than salt in the urine. This initial response is thought to occur as a result of local tissue hypoxia, acidosis, or both. Cardiac effects of hypercalcemia include shortened plateau phase of the action potential, increased rate of diastolic depolarization of sinus node cells, and delayed atrioventricular conduction. An overview of the tissue and systemic changes of aging is presented in Table 4-5. A factor important to the concepts of ventilation and perfusion is the matching of an adequate volume of air in the alveoli to adequate pulmonary blood low. It is increasingly important for paediatricians to be able to recognize genetic disorders and to know when to enlist the help of a clinical geneticist. There is overlap in the mechanism of atrial tachycardia and atrial lutter, and several types of lutter have been described. Blood low through the veins is essentially accomplished by forces outside the veins-the skeletal muscle, intraabdominal and intrathoracic pumps. Epithelial cells of the skin and those that line the gastrointestinal, genitourinary, and respiratory tracts are tightly linked and provide an initial barrier to infection.
Imbalances of body luid concentration are recognized by abnormal serum sodium concentration. But it also can mean the actual physical and mental state of tension ("I feel stressed"). Gram-negative bacteria include Escherichia coli, Klebsiella pneumoniae, Enterobacter aerogenes, Serratia marcescens, Pseudomonas aeruginosa, and Proteus species. Contractility depends on the amount of free calcium ions available in the cardiac muscle cells after each electrical impulse. Cyclosporine (Sandimmune) is a more selective immunosuppressant that reversibly suppresses T-helper cells in the G0 or G1 phase of the cell cycle without killing them. It occurs when a person receives blood from someone with a different blood group type (Table 10-4). Infants with Wiskott-Aldrich syndrome are treated with antibody replacement therapy, and antibiotic therapy. The surgeon generally removes a margin of normal-appearing tissue around the resected tumor to ensure complete tumor removal. Air enters the pleural space during inspiration but cannot escape during expiration. Normally, venous return is equal to cardiac output because the circulatory system is just that-a circuit. Some alleles are not clearly dominant or recessive and result in a blending or codominant expression of the trait. Endocytosis of certain macromolecules is regulated by speciic receptors on the cell surface. Urethral strictures are usually diagnosed by cystoscopy or retrograde urethrography, which would demonstrate a narrowing of the urethra. The phases include an asymptomatic phase, a plethoric or erythrocytic phase, an inactive phase, and a spent phase when anemia develops. Contact with an antigen or antigens usually leads to induction of a normal protective immune response. A fall in aortic blood pressure can signiicantly reduce coronary perfusion, particularly in vessels with high resistance to low. An understanding of these mechanisms is essential to exploring pathophysiologic alterations. The airways become inlamed and narrowed from capillary dilation, swelling from exudation of luid, iniltration with inlammatory cells, increased mucus production, loss of ciliary function, and loss of portions of the ciliated epithelium. Radiographically, this appears as a "honeycomb lung" and indicates end-stage disease. In Scotland, all children and adolescents may consent to treatment irrespective of age, so long as they are deemed competent to do so. If both alleles are identical, the individual is said to be homozygous for that gene. If a child is likely to be difficult to sedate, then consider whether a short-acting general anaesthetic, administered by a paediatric anaesthetist, is safer and kinder to the child. The negative cell interior attracts K+ in to the cell, whereas the huge K+ concentration gradient favors movement of K+ out of the cell. Hairdressers exposed to bleach and hair spray are at risk for developing obstructive lung disease. Pain is commonly accompanied by nausea, vomiting, diaphoresis (sweating), and shortness of breath. Elevation of the legs, slow position changes, and the use of pressure stockings on the legs may help prevent peripheral pooling. Hypoxemia, acute pain, and psychological distress are important clinical causes of hyperventilation that leads to respiratory alkalosis. Common causes of cellular injury include hypoxic injury, nutritional injury, infectious and immunologic injury, chemical injury, and physical and mechanical injury.
The catheter is then manipulated in to the left ventricle or left atrium to assess chamber pressures, and a ventriculogram is obtained. As methods improve, gene therapy will become an increasingly important part of cancer prevention and management. In this disorder, maternal antibodies bind to and lyse fetal red blood cells (see Chapters 10 and 13). An increase in afterload will result in a decrease in stroke volume unless contractility or preload (or both) is adjusted to compensate. From MacGregor J: Introduction to the anatomy and physiology of children: a guide for students of nursing, child care and health, ed 2, New York, 2008, Routledge. Clinical manifestations of hypocalcemia are those of increased neuromuscular excitability: positive Trousseau sign, positive Chvostek sign, paresthesias, muscle twitching and cramping, hyperactive relexes, carpal spasm, pedal spasm, tetany, laryngospasm, seizures, and cardiac dysrhythmias. The maximal life span is limited by the aging process itself rather than by the ravages of disease. The impaired cardiac function of severe hypophosphatemia results from decreased cardiac contractility and stroke work concurrent with increased left ventricular end-diastolic pressure and may cause congestive cardiomyopathy. In some cases of myocarditis, the immune system reaction against the myocardium appears to be the primary cause. The nephron is the functional unit of the kidney, performing all iltration, reabsorption, and secretory functions. Anabolism refers to energy-using metabolic processes or pathways that result in the synthesis of complex molecules such as fats. In this case, 95% of all people with ankylosing spondylitis have a positive B27 phenotype. Electrolyte homeostasis is the interplay of electrolyte intake and absorption, electrolyte distribution, electrolyte excretion, and electrolyte loss through abnormal routes. Once initiated by the causal agent, proliferation and necrosis of bronchiolar epithelium occur, producing obstruction and increased mucus production. Hypernatremia is caused by a gain of relatively more salt than water or by a loss of relatively more water than salt. The consequences of duplications are generally less severe than those from loss of genetic material. At about the same time that the atrial and ventricular septal structures are being elaborated, the common ventricular outlow tract, the truncus arteriosus, is divided in to the pulmonary and aortic channels. Heart failure, bone marrow and fat emboli, shock, and organ failure are common causes of death. However, the right side of the heart has an increased workload because of the extra shunt blood. However, the enzymes of the transport chain have harnessed energy from the transported electrons in the form of a proton (H+) gradient. Although the fetus grows normally, the infant is severely affected with absent lymphoid tissue, absent T lymphocytes, and absent immunoglobulins. The goal of therapy for iron deiciency anemia is to supply suficient iron to repair the hemoglobin deicit and to replenish iron stores. Fluid imbalances fall in to two major categories: imbalances of extracellular luid volume (saline imbalances) and imbalances of body luid concentration (water imbalances). As the systolic and diastolic pressures rise from normal levels, mortality from ischemic heart disease and stroke also increases linearly and progressively. Occasionally they may lodge underneath the upper eyelid or become embedded in the cornea causing intense irritation and excessive lacrimation. In obese adults, with a much larger proportion of body fat, less of the body weight is water. Thus, an understanding of cellular mechanisms is essential for health care providers and fundamental to the discussions of pathophysiologic processes presented throughout the remainder of this text. It is an antigen-antibody reaction causing the release of potent chemicals that can lead to extreme, even life-threatening reactions in susceptible individuals. In the lungs, the reaction proceeds in reverse, producing carbon dioxide, which is eliminated by the lungs. Patients with heart failure may experience more symptoms when they are in atrial ibrillation because the usual "atrial kick" that normally adds 15% to 20% more blood to the ventricle before systole is lost and therefore cardiac output may be reduced. Arterial pressures fall to their lowest value just before semilunar valve opening.
These proliferation-promoting signals at the cell surface are transmitted to the Rb protein by way of cyclin-dependent signaling pathways within the cell. Hyposensitization in most cases of occupational asthma is ineffective because of lack of an IgE antibody reaction and because the chemicals that cause symptoms usually are toxic when injected. Each lobule contains one to four seminiferous tubules that if stretched to full length would measure approximately 60 cm. Serum levels of growth hormone also increase, at least initially, following a variety of intensely stressful physical or psychological stimuli, such as strenuous exercise or extreme fear. Usually, an underlying disease such as diabetes, alcoholism, or another general debility predisposes the patient to such an aggressive infection. Examples of acyanotic defects are coarctation of the aorta, atrial and ventricular septal defects, and patent ductus arteriosus. A hallmark of shock is failure of the microcirculation to appropriately autoregulate blood low. Conditions that cause low blood oxygen tension may contribute to continued patency. Renal blood low decreases after the fourth decade at an approximate rate of 10% per decade because of vascular changes, especially in the cortical blood vessels. Airways are hyperreactive, and patients may present with extreme dyspnea, orthopnea, and agitation. For example, cells of the more aggressive or poorly differentiated prostate cancers have more indistinct cell borders, larger nuclei, and loss of acinar (gland) formation. Between the third and ninth weeks of gestation the embryo is very vulnerable to teratogenesis, with the fourth and ifth weeks being the time of peak susceptibility. Shreeram S, et al: Prevalence of enuresis and its association with attention-deicit/hyperactivity disorder among U. Fibrinous exudate is sticky and thick and may have to be removed to allow healing; otherwise, scar tissue and adhesions may develop. For example, new mutations for Huntington disease are rare, whereas 80% of individuals with achondroplasia represent new mutations. The propofol infusion syndrome is thought to be related to the total dose of propofol infused, i. Electrolyte disturbances, hyperkalemia Allow blood to warm at room temperature (<1 hr). Goblet cells have abundant mucus granules in the cytoplasm, and their apical surface is devoid of cilia. Racial15-18 and socioeconomic stressors8,19-21 as well as childhood abuse22 can produce many of the manifestations of stress described in this chapter. Arteriosclerosis is a complex condition that produces structural changes in arteries. Adolescence is therefore filled with major changes that need to be taken in to account when caring for adolescents with health-related problems. Peripartum cardiomyopathy is the term applied to cases of dilated cardiomyopathy discovered just before or just after delivery. Both types are excitable: they are able to produce and transmit action potentials. If cells are no longer needed, they activate a cellular death pathway resulting in cell suicide. In hemoglobin S, valine is substituted for glutamic acid in the sixth position of the chain, rather than the normal coniguration. Protein synthesis still holds a predominant place in understanding how genes direct cell structure and function. Decisions about the data needed are based on the initial clinical presentation and a working knowledge of pathophysiology, which guide hypothesis generation about probable etiologies. M1, M2, and M3 types result in granulocytic leukemia; M4 has characteristics of monocytic and granulocytic leukemia; M5 is monocytic; M6 is associated with erythroid leukemia; and M7 is associated with megakaryocytic leukemia.
The presence of the Y chromosome determines the sex of these individuals to be male; however, the extra X chromosomes result in abnormal sexual development and feminization. Urea becomes concentrated in the tubule iltrate when electrolytes and water are removed in the proximal tubule and loop of Henle. How are history, clinical manifestations, and laboratory studies used to differentiate the various forms of polycythemia What are the appropriate treatment measures for each of the common types of anemia and polycythemia Blood is a critical body luid composed of formed elements and cells suspended in plasma that circulates through the cardiovascular system. Most of these essential nutrients must be obtained from external sources because the cell is unable to manufacture them. The right side of the heart receives blood from the systemic circulation and recirculates it through the body by way of the aorta. An increase in intracellular free Ca2+ concentration during phase 4 can trigger Ca2+ inlux across the plasma membrane and release more Ca2+ from the sarcoplasmic reticulum, resulting in an action potential. This approach builds on the way in which students learn anatomy and physiology and has its roots in medical specialization. Decreased renal perfusion also results if large volumes of luid collect in extravascular spaces as in edema (interstitial space) or ascites (peritoneal space). Skeletal muscle contracts in response to stimulation from the motor neurons of the nervous system (see Chapter 50). The C5b fragment combines with C6, C7, C8, and multiple units of C9 to form a large porelike structure (C5b6789) called the membrane attack complex. This results in a system that can respond quickly to the changing needs of the body. Filtration relects the difference between the combined forces that push luid out of the capillary (capillary pressure and interstitial luid colloid osmotic pressure) and those that attempt to hold luid in the capillary (plasma colloid osmotic pressure and interstitial luid pressure). Symptoms, when present, may include fatigue, weight loss, diaphoresis, bleeding, and abdominal discomfort from the enlarged spleen. Conditions that increase myocardial cell death are thought to stimulate recruitment of stem cells in to the myocardium. The pathologic changes leading to alveolar destruction are associated with the release of proteolytic enzymes from inlammatory cells such as neutrophils and macrophages. Self antigens may be present in such high quantity that reactive lymphocytes are killed. A, An action potential is initiated by the opening of sodium channels in a section of membrane. Ultrasonography differentiates the solid mass of a neoplasm from luid-illed cysts. The importance of prompt reporting of any new breast symptoms to a health professional should be emphasized. The insulin receptor and most growth factor receptors are protein kinase receptors that phosphorylate and activate intracellular enzyme cascades. These bacteria produce toxins and degradative enzymes that allow the infection to spread rapidly through the necrotic tissue. Psychotherapy, exercise therapy, cognitive behavioral therapy, and music therapy all have demonstrated varying degrees of success. For example, burn victims who have lost portions of their skin barrier are at high risk for infection. Oxygen consumption in the myocardium is reduced, resulting in less eficient function when stressed and an overall decreased cardiac reserve. A second pulmonary function test known as the diffusion capacity measures the ability of the alveolar gases to diffuse in to the capillary blood. The membrane attack complex has a direct cytotoxic effect by attacking cell membranes and disrupting the lipid bilayer. Prevention of the initiating mutation may be dificult inasmuch as carcinogens are ubiquitous; however, therapies to prevent promotion and progression could render the initial mutation harmless. Depending on its severity, aortic stenosis is correctable and associated with a good prognosis.
There are two types of endocytosis, which are differentiated by the size of the particles ingested. Advances in technology have allowed direct visualization of capillary low through tissue beds and conirmed the presence of perfusion abnormalities in the microcirculation. Although it is not very accurate, it is helpful in identifying men who are at risk of having cancer. The disruption of the globin balance causes the normal chains to accumulate and precipitate within the cytoplasm. If some self products are not exposed to the developing T cells, the product will not be recognized as self and will subsequently be attacked. When the ligand binds to the receptor, an intracellular domain is changed in to an active coniguration that can interact with inactive trimeric G-proteins. The pulmonary artery catheter could become wedged and necrosis could occur, or the catheter could slip back in to the ventricle and irritate the myocardium, causing ventricular dysrhythmias. However, other medications, such as anesthetics, alcohol, antibiotics, and steroids, also affect the immune response and can lead to secondary immunosuppression. A common cause of diarrhea is the protozoa Cryptosporidium, which infects the intestinal epithelial lining. Common features are marked shortness of breath, pain on inspiration, hypotension, cyanosis, and hypoxemia. The remainder of this chapter will deal with the physiologic processes of male reproduction. This molecular abnormality is the target of new drug therapies to eliminate neoplastic cells. Regardless of whether the emboli are blood clots or an alternative type of material (see Table 21-3), once they are released in to the venous system, the undissolved material travels to the pulmonary vasculature. The particular coniguration of carbohydrate molecules on the lipid or protein is believed to serve as an "address label," directing them to the correct destination within the cell. The sensitivity and speciicity of available tumor markers varies widely; at this time, no tumor marker is reliable enough to replace cystoscopy. Like hydroceles, they are benign and do not require treatment unless they cause discomfort. Amblyopia Permanent loss of visual acuity in an eye that has not received clear images in the sensitive period of visual development (up to age 7yrs). The hydrostatic pressure remains fairly constant along the length of the capillary and exerts an average force of approximately 60 mm Hg. Impact on the adolescent Teenagers with a chronic illness are disadvantaged compared with their healthy peers. Auscultated and oscillometric blood pressure measurements are burdened with the potential of measurement error, in both reliability and validity (Table 16-3). Urethral valves, istulas, and malpositioning of the urinary meatus (hypospadias, epispadias) are related to abnormal embryonic development. It can be administered intramuscularly or intravenously, depending on the product. The thymus gland is responsible for exposing developing T cells to self products produced in the thymus or carried to the thymus gland. The linings of the respiratory tract and some glands contain pseudostratiied epithelium. Increased intracranial pressure should be suspected in the leukemia patient who complains of nausea, vomiting, headache, and visual changes. Hyperphosphatemia is common in people who have oliguric renal disease, either acute or chronic. Like the opiate drug morphine, endorphins raise the pain threshold (reduce pain) and produce sedation and euphoria.
The reservoir may be a human, as in the inluenza virus; an animal, as in rabies; an insect, as in West Nile virus; or soil, as in enterobiasis (pinworm infestation). Transition should be carefully planned and the adolescent patient, and their family, should be given plenty of time to consider and prepare. Vascular obstruction may be manifested as acute ischemia of the ingers and toes, with pain, pallor, and poor capillary reill. Molluscum contagiosum Common pox virus infection affecting infants and young children. Large ventricular septal defects may be apparent at birth because of rapidly developing right-sided heart failure and a loud systolic murmur. Segmental, midline and multiple haemangiomas may need further investigation (see b p. Chemokines present on the endothelium enhance the binding afinity of integrins so the neutrophil can attach irmly to the vessel wall. If an individual is able to coordinate urination at a suitable location and desired time, we consider the individual to be continent. The distending pressure (P) is the transmural pressure, or pressure on one side of the vessel wall minus the pressure on the other side of the blood vessel. Bradykinin has contractile effects on smooth muscle and forces the ductus arteriosus walls to constrict. Electrolyte Loss Through Abnormal Routes When electrolytes exit the body through routes other than the normal urine, feces, and sweat, this may be termed electrolyte loss through abnormal routes. T lymphocytes capable of reacting with self tissue are thought to be destroyed or permanently inactivated during development in the thymus. When phagocytosis is incomplete, a collection of dead neutrophils, bacteria, and cellular debris, called pus, may form at the site. Oxandrolone is an anabolic steroid designed speciically to promote weight gain, particularly lean body mass. It stated that the parental right to determine whether or not a child below the age of 16yrs will or will not have medical treatment terminates if and when the child achieves sufficient understanding and intelligence to enable him to understand fully what is proposed (see also b p. Common symptoms of cystitis in children include fever, irritability, poor feeding, vomiting, diarrhea, and ill appearance. Through capacitation and the acrosome reaction, spermatozoa acquire the ability to fertilize ova residing in the female reproductive tract. Fibroblasts are found all over the body and are thought to originate in mesenchymal primitive tissue. Hypernatremia also is called water deicit, hypertonic syndrome, and hyperosmolality. The purpuric lesions associated with inherited connective tissue disorders, such as Ehlers-Danlos syndrome, often are accompanied by large ecchymoses and hematomas. Within these connections are specialized proteins that form a luid-illed pore (gap junction) between the fused cells. However, cells that possess the same receptor may respond very differently to a particular ligand. The irst occurs in the liver, resulting in the formation of 25-hydroxycholecalciferol. The bicarbonate buffer system is the most important buffer in the extracellular luid. The presence, position, and activity of gene regulatory proteins may be regulated by various signaling cascades within the cell. Most grading systems classify tumors in to three or four classes of increasing degrees of malignancy. In certain populations, Staphylococcus saprophyticus and group B Streptococcus have been identiied. The role that immune cytokines play in shock has been studied extensively in septic shock. As the biochemical processes governing promotion and progression become clearer, strategies for blocking these stages continue to be developed.
Digitalis toxicity and excessive catecholamine stimulation may contribute to this mechanism. The difference between systolic and diastolic blood pressure is termed the pulse pressure. This is seen more commonly in oriental children and resolves as the face grows although repeated corneal abrasion may necessitate surgical correction. Another example is the study of the chemical changes that take place in body tissue as the result of inlammation. Oxygen free radicals also have been linked to initiation of the inlammatory cascade. In addition, a right-toleft shunt from an open foramen ovale or patent ductus arteriosus may increase the hypoxemia. Risk factors and treatment are much the same as those for nephrolithiasis; however, manifestations of urolithiasis in the ureters or bladder differ. The goal of therapy is to identify the offending agent and prevent further exposure. In men with varicoceles surgical repair or embolization can often improve fertility. After that time, neurologic impairment is characterized by development of weakness, loss of previously accomplished developmental milestones, hypotonia, or hypertonia. In open patch testing, the suspected allergen is applied twice daily to the upper arm and left uncovered for 2 days. This test is highly sensitive (more than 99%) and speciic (more than 99%) in high-risk populations. It is also seen in the Middle East, parts of India and Pakistan, and throughout Southeast Asia. Homocystinuria Due to deficiency in cystathionine beta-synthase, resulting in increased urinary homocystine and methionine excretion. These disorders can affect lymphocytes, antibodies, phagocytes, and complement proteins. The pain induced by nephrolithiasis makes the patient acutely uncomfortable and is often accompanied by nausea and vomiting, diaphoresis, tachycardia, and tachypnea. B and C, Airway cilia have the classic microtubular arrangement of motile cilia, namely, nine peripheral doublets and two central singlets. Pathophysiology includes four interrelated topics: etiology, pathogenesis, clinical manifestations, and treatment implications-the framework used throughout this textbook. The signiicance of thrombosis rests in the ability of a clot within a blood vessel to reduce low and increase turbulence, which enhances thrombus enlargement and the formation of more thrombi. In patients with spurious polycythemia caused by smoking, the problem is usually chronic, and the symptoms attributable to the hyperviscosity described for polycythemia vera are often found. By this method, known as herd immunity, the disease can be controlled or eliminated without immunizing everyone, as long as a high enough percentage of the population is immunized. After correction for age, gender, risk factors, and pharmacologic treatment of hyperlipidemia, one study reported the least amount of coronary artery calciication to be among Asian men and women. Cardiac effects of hypocalcemia arise from the prolonged plateau phase of the cardiac action potential, impaired atrioventricular and intraventricular conduction, and impaired myocardial contractility, which can cause heart failure. In the absence of surfactant, which reduces alveolar surface tension, the alveoli tend to collapse-a condition called atelectasis. A comparison of viruses, transmission characteristics, and resulting disease processes is presented in Table 8-5. Mortality rates range from 70% to 90% in hospitals or correctional facilities in Florida and New York, with a median survival of 4 to 16 weeks. Allostasis is essentially the activation of these stress responses to evoke changes that return the organism to homeostasis. B-cell and T-cell functions are usually normal, except for the inability of the T cells to respond to Candida infections. Throughout the world, secondary lymphedema is most commonly caused by an infection by ilarial worms that migrate to the nodes of the lymphatic system, producing an obstruction of low. Immune cells are particularly adept at producing free radicals, which can attack host cell membranes and induce signiicant cell injury.