Hypersensitivity definition

Demoly, P. and Rebelo Gomes, E., Drug hypersensitivities definition, epidemiology and risk factors, Eur. Ann. Allergy Clin, Immunol., 37, 202, 2005. 

Toxicology. The acute oral and dermal toxicity of naphthalene is low with LD q values for rats from 1780—2500 mg/kg orally (41) and greater than 2000 mg/kg dermally. The inhalation of naphthalene vapors may cause headache, nausea, confusion, and profuse perspiration, and if exposure is severe, vomiting, optic neuritis, and hematuria may occur (28). Chronic exposure studies conducted by the NTP ia mice for two years showed that naphthalene caused irritation to the nasal passages, but no other overt toxicity was noted. Rabbits that received 1—2 g/d of naphthalene either orally or hypodermically developed changes ia the lens of the eye after a few days, foUowed by definite opacity of the lens after several days (41). Rare cases of such corneal epithelium damage ia humans have been reported (28). Naphthalene can be irritating to the skin, and hypersensitivity does occur. 

Adverse event. Unwanted effects that occur and are detected in populations. The term is used whether there is or is not any attribution to a medicine or other cause. Adverse events may be known parts of a disease that are observed to occur within a period of observation, and they may be analyzed to test for their frequency in a given population or trial. This is done to determine if there is an unexpectedly increased frequency resulting from nondisease factors such as medicine treatment. The term adverse event or adverse experience is used to encompass adverse reactions plus any injury, toxicity, or hypersensitivity that may be medicine-related, as well as any medical events that are apparently unrelated to medicine that occur during the study (e.g., surgery, illness, and trauma). See definition of Adverse reaction. 

Antilymphocyte antibody acts primarily on the small, long-lived peripheral lymphocytes that circulate between the blood and lymph. With continued administration, "thymus-dependent" lymphocytes from lymphoid follicles are also depleted, as they normally participate in the recirculating pool. As a result of the destruction or inactivation of T cells, an impairment of delayed hypersensitivity and cellular immunity occurs while humoral antibody formation remains relatively intact. ALG and ATG are useful for suppressing certain major compartments (ie, T cells) of the immune system and play a definite role in the management of solid organ and bone marrow transplantation. 

In addition to acute and chronic schizophrenia, the neuroleptics are sometimes used in the management of mania, delirium, and severe agitation, whatever the cause of these symptom complexes. It must be noted that unlike parkinsonism, where a definite dysfunction in the DA system has been established, for schizophrenia and other psychiatric diseases, no unequivocal evidence has yet been presented to prove that there is a disturbance of the DA system (e.g., dopaminergic overactivity or receptor hypersensitivity). In untreated schizophrenics the production of DA metabolites is normal. Conflicting results have been obtained in studies of the DA receptors in schizophrenics (11,12,13), but in the case of patients who have not received neuroleptics, the receptor density and affinity appear to be normal (13). The "dopamine hypothesis" in these disorders derives from the beneficial effects of drugs that block DA receptors. 

A positive PST indicates the presence of IgE but cannot univocally confirm that actual hypersensitivity for definite food allergy still exists. The diagnostic value of PST in children with food allergy is shown in Table 3.3.6 (Eigenmann and Sampson, 1998 Sporik et al., 2000 Hill et al., 2004) (Table 3.3.6). 

A similar group of products which do not correspond strictly to the definition of food additives is composed of raw foods, which, owing to their sensory properties, are added in small quantities to proper food products (condiments, herbs, vegetables, and oils). They can, however, produce allergenic or nonallergenic hypersensitivity response. 

It has also been hypothesized that a type I hypersensitivity reaction may be involved in some patients. A definitive pathogenic mechanism for episcleritis has still not been established. 

Anaphylactic shock has been described after intranasal hydrocortisone acetate, intramuscular methylprednisolone (SEDA-21, 419) (251), intravenous methylprednisolone (SEDA-22, 448) (252), intramuscular dexamethasone (SEDA-22, 448) (253), and intra-articular methylprednisolone (SEDA-22, 449) (254). A life-threatening anaphylac-tic-like reaction to intravenous hydrocortisone has been described in patients with asthma (255). Acute laryngeal obstruction has been described for the first time after the intravenous administration of hydrocortisone (SEDA-22, 449) (256). There is some reason to believe that sodium succinate esters are more likely to cause hypersensitivity reactions (SEDA-17, 449), but unconjugated glucocorticoids can definitely produce allergy in some cases (SEDA-16, 452). 

Beck studied the acute toxicity, upon intraperitoneal injection, to mice of each compound. The anhydride was definitely less toxic. Erythritol in doses of 0.8 to 0.9 g. per 100 g. of mouse caused definite hypersensitivity, later convulsions, followed by death in two to three hours. Doses of 1.8 g. per 100 g. of mouse of erythritan produced convulsions followed by a lingering depression, ending usually in the death of the animal. 

As indicated in Figure 1, the other side of the immunotoxicity continuum is manifested either as a hypersensitivity response or as an autoimmune disease. A hypersensitivity response is an acquired immune response (i.e., by definition, it is manifested on second contact with a particular antigen) which... 

Toxicology of Chemical Respiratory Hypersensitivity Table 3.4 Case definition of multiple chemical sensitivity ... 

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