Resistance to infection

The first clues to the treatment of scurvy occurred in 1535—1536 when Jacques Cartier, on advice from Newfoundland Indians, fed his crew an extract from spmce tree needles to cure an epidemic. Various physicians were recommending the use of citms fmits to cure scurvy in the mid-sixteenth century. Two hundred years later, in 1753, it was proved by Dr. James Lind, in his famous clinical experiment, that scurvy was associated with diet and caused by lack of fresh vegetables. He also demonstrated that oranges and lemons were the most effective cure against this disease. In 1753, inM Treatise on the Scurvy[ Lind pubhshed his results and recommendations (7). Eorty-two years later, in 1795, the British Navy included lemon juice in seamen s diets, resulting in the familiar nickname "limeys" for British seamen. Evidence has shown that even with undefined scorbutic symptoms, vitamin C levels can be low, and can cause marked diminution in resistance to infections and slow healing of wounds. 

Avoid contact with those who have an infection because resistance to infection may be decreased. 

MANAGING INFECTION. The nurse should report any slight rise in temperature, sore throat, or other signs of infection to the primary health care provider as soon as possible because of a possible decreased resistance to infection during glucocorticoid therapy. Nursing personnel and visitors with any type of infection or recent exposure to an infectious disease should avoid patient contact. 

MANAGING HONE MARROW SUPPRESSION. Bone marrow suppression is a potentially dangerous adverse reaction resulting in decreased production of blood cells. Bone marrow suppression is manifested by abnormal laboratory test results and clinical evidence of leukopenia, thrombocytopenia, or anemia For example, there is a decrease in the white blood cells or leukocytes (leukopenia), a decrease in the thrombocytes (thrombocytopenia), and a decrease in the red blood cells, resulting in anemia Fhtients with leukopenia have a decreased resistance to infection, and the nurse must monitor them closely for any signs of infection. 

In severe cases, or those refractory to treatment, truncal and limb weakness may be accompanied by involvement of masticatory, bulbar, and respiratory muscles. However the most life-threatening clinical manifestations are those affecting the gastrointestinal tract, since stomach ulceration can occur and death from perforation and peritonitis are not unknown. Medication with steroidal antiinflammatory agents is necessary but weakens the childrens resistance to infection, so that systemic spread of usually self-limiting disorders, such as candidiasis, may occasionally occur. 

C22-0078. Why does exposure to radiation in cancer therapy result in nausea and reduced resistance to infection ... 

Low-dose dopamine is not without adverse reactions and most studies have failed to evaluate its potential toxicities. Adverse reactions that may be associated with low-dose dopamine include tachycardia, arrhythmias, myocardial ischemia, depressed respiratory drive, and gut ischemia. Low-dose dopamine has also been postulated to impair resistance to infection through a reduction in prolactin concentrations.21 Furthermore, significant overlap in receptor activation occurs. Therefore, doses considered to activate only dopamine receptors may increase cardiac output and blood pressure through dopamine s effect on 3- or a-adrenergic receptors. 

Bacterial keratitis is a broad term for a bacterial infection of the cornea. This includes corneal ulcers and corneal abscesses. The cornea in a healthy eye has natural resistance to infection, making bacterial keratitis rare. However, many factors predispose a patient to bacterial infection by compromising the defense mechanisms of the eye (Table 60-5).19... 

Anyone over 6 years of age who has a disease or condition or is taking any drug that lowers the body s resistance to infection, such as... 

Discuss characteristics of the skin that render it resistant to infection. 

Healthy bone tissue is normally resistant to infection but may become susceptible under certain conditions.9 Bone can become infected (1) via the presence of bacteria in the blood-... 

Dessein, A.F., Parker, W.L., James, S.L. and David, J.R. (1981) IgE antibody and resistance to infection. I. Selective suppression of the IgE antibody response to Trichinella spiralis infection. Journal of Experimental Medicine I d ), 423-436. 

A remarkable indirect strategy for chemical defense is found in embryos of the shrimp Palaemon macrodactylusy which are resistant to infection by the pathogenic fungus Lagenidium callinectesy a known pathogen of many crustaceans. This resistance is caused by bacteria on the surface of the embryos... 

There is very little information on cultivar differences with respect to (i) resistance to infection by P. verrucosum and (ii) OTA formation (Hokby et al., 1979 Axberg el al., 1997). The latter performed a laboratory experiment with six artificially inoculated cultivars of barley and three of wheat. After incubation for 23 weeks at approximately 19% moisture, the barley cultivars contained between 6 and 350 and the wheat cultivars between 25 and 890 ng OTA g 1 grain. In another study, Elmholt and Rasmussen (2005) reported that two of four cultivars of spring spelt from the same field contained 18 and 92 ng OTA g 1, respectively, while the other two contained less than 0.5 ng OTA g As differences in OTA neither correlated with moisture content at harvest nor with the level of P. verrucosum, they were probably caused by differences in cultivar sensitivity. This should, however, be further studied. 

Upper respiratory irritation, reduced resistance to infection by Salmonella, and increased pulmonary macrophages all effects disappeared by day 63 No adverse effects noted at low concentration. At 3700 pg/L, histopathology of lung, liver, and kidney... 

The well-appreciated adverse effects of glucocorticoids include hyperglycemia, hypertension, osteoporosis, fluid retention and electrolyte disturbances, myopathies, psychosis, and reduced resistance to infection. In addition, glucocorticoid use may cause adrenocortical suppression. Specific regimens for withdrawal of glucocorticoid therapy have been suggested. 

The majority of early publications that can be reasonably identified as comprising immunotoxicology reported altered resistance to infection in animals exposed to various environmental or industrial chemicals. Authors logically concluded that xenobiotic exposure suppressed immune function since the immune system is ultimately responsible for this resistance to infection. Subsequent studies demonstrated that suppression of various cellular and functional endpoints accompanied or preceded increased sensitivity to infection, and that administration of known immunosuppressants likewise decreased host resistance. The human health implications of these studies, that chemical exposure reduced resistance to infection, drove the initial focus of many immunotoxicologists on functional suppression, and provided the theoretical and practical underpinnings of immunotoxicity testing. 

Follow-on studies are also recommended as needed. These include determination of potential test article effects on blood or tissue immunophenotypes (by flow cytometry or immunohistochemistry), natural killer cell, macrophage, or neutrophil function, host resistance to infection or tumors, and cell-mediated immunity. The important issue in all of these guidelines is this do not ignore signs of immunotoxicity, and assess these findings when observed. 

Luebke, R.W., Assessment of host resistance to infection with rodent malaria, in Methods in immunotoxicology, vol. 2, Burleson, G.R., Dean, J.H. and Munson, A.E., Eds., Wiley-Liss, New York, 1995, p.221. 

Gallium arsenide altered host resistance in B6C3F1 mice, resulting in increased resistance to infection by Streptococcus pneumoniae and Listeria monocytogenes [18], but increased susceptibility to Staphylococcus aureus [19] and to tumor development by B16F10 melanoma cells [18], However, inhalation exposure to As203 led to increased... 

Respiratory allergies and infections are the most common form of illness in the United States and Europe and account for more missed school and work days than any other disease [1], A substantial body of experimental work has clearly shown that airborne toxicants such as tobacco smoke, ozone, and other air pollutants can alter many aspects of the host defense network to either decrease resistance to infection, or exacerbate respiratory allergies and asthma [2], Exposure to air toxicants can suppress a number of key host defenses including mucociliary clearance in the airways, pulmonary macrophage function, and development of specific immune responses such as IgG antibody production and cell mediated immunity. In contrast, immune stimulation in the form of increased T cell activity and IgE antibody formation has also has been shown to occur under some circumstances, resulting in increased incidence or severity of allergic lung disease. 

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