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Query: UMLS:C0033774 (pruritus)
 14,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Both hard and soft lens wearers develop a syndrome of decreased tolerance, increased mucus, mild itching, and giant papillary excrescences in the upper tarsal conjunctiva that resemble a varnal conjunctivitis. In the fully developed syndrome, the upper tarsal plate has an increase in stringy mucus and is covered by large papillae crowded together. The syndrome develops after months to years of otherwise successful lens wear and occurs in users of all types of soft and hard lenses. Histologic examination of tissues from 55 patients with well-developed giant papillary conjunctivitis compared with tissue from 15 normal people showed three findings characteristic of the syndrome: (1) mast cells in the epithelium, (2) eosinophils in the epithelium and substantia propria, and (3) basophils in the epithelium and substantia propria. Plasma cells and lymphocytes per cubic millimeter were not increased in detailed counts of 15 patients and 15 normal individuals. It is proposed that the number of plasma cells and lymphocytes cannot increase much beyond the level already present in normal conjuctiva and further influx of mononuclear inflammatory cells is the impetus for growth of the papillae. It is proposed that giant papillary conjunctivitis is a generalized response of the upper tarsal conjunctiva.
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PMID:Giant papillary conjunctivitis induced by hard or soft contact lens wear: quantitative histology. 71 78

A syndrome that occurred in both hard and soft contact lens wearers was characterized by increased mucus, itching, decreased lens tolerance, and giant papillae in the upper tarsal conjunctiva. It developed in as few as three weeks with soft lens wearers but also occurred after months or even years of successful wear. The histology was characterized by basophils, eosinophils, and mast cells in the epithelium, and these cells as well as increased numbers of lymphocytes, plasma cells, and polymorphonuclear leukocytes in the stroma. The syndrome may be immunologic in origin with deposits on the lenses as the antigen, and the syndrome may be a major cause of difficulty in wearing contact lenses once they have been successfully fit.
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PMID:Giant papillary conjunctivitis in contact lens wearers. 86 69

The eye reacts to foreign substances through a variety of specific and non-specific defense mechanisms. Constantly exposed to a great variety of microorganisms, the eye is capable of protecting itself without altering its own structure and function. Its resistance relies upon anatomic and physiological properties of its external components (eyelids, tears, conjunctiva and cornea). Most of the times, the conjunctiva becomes affected, resulting in a clinical picture of conjunctivitis where allergy predominates, expressed as allergic rhinoconjunctivitis, allergic conjunctivitis, vernal keratoconjunctivitis, giant papillary conjunctivitis and flictenular conjunctivitis. The physiopathology is considered to be of type I reaction (IgE mediated). Frequent complains often associated with other allergic diseases are: pruritus, tearing, photofobia and ocular redness. The diagnosis of allergic conjunctivitis in done by means of a throughout clinical history, conjunctival citology and evaluation of specific IgE with immediate skin tests. Treatment is symptomatic (antihistamines, antibiotics and/or topic steroids), but prevention (environmental control and sodium cromoglycate) and specific immunotherapy must be considered.
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PMID:[Allergic conjunctivitis]. 130 89

Exposure to environmental tobacco smoke (ETS) is a potential occupational carcinogen according to guidelines of the Occupational Safety and Health Administration (OSHA) carcinogen policy (1). Exposure to ETS in the workplace may represent a substantial contribution to lifetime ETS exposure (2). For many persons, ETS irritates the conjunctiva of the eyes (accompanied by reddening, itching, and increased lacrimation) and the mucous membranes of the nose, throat, and lower respiratory tract (accompanied by itching, coughing, and sore throat) (3). As part of the 1988 National Health Interview Survey-Occupational Health Supplement (NHIS-OHS), CDC measured the degree of discomfort caused by ETS in the workplace. The NHIS-OHS collected information on cigarette smoking, workplace smoking restrictions, and perceived discomfort caused by ETS at the workplace. This report summarizes survey findings and describes efforts to reduce ETS at the workplace.
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PMID:Discomfort from environmental tobacco smoke among employees at worksites with minimal smoking restrictions--United States, 1988. 158 92

Levocabastine is a new H1 receptor blocking antihistamine which is intended for topical use in the treatment of allergic conjunctivitis. The protective effect of the drug in conjunctival provocation test (CPT) was evaluated in a double blind study of 25 children aged 9-17 years with confirmed pollen allergy. One drop of levocabastine, cromoglycate or placebo was instilled into the conjunctival sac of both eyes. After 15 min CPT was performed, starting with 320 BU of pollen extract. The allergen dose was increased every 10 min in half 10-log steps in the right eye until a positive reaction occurred, or the top dose 320,000 BU was reached. The lowest dose resulting in a positive CPT reaction, i.e. at least 50% of the conjunctiva with erythema, was defined as the allergenic threshold dose (ATD). Pretreatment with levocabastine resulted in a median ATD of 32,000 BU, compared with 10,000 after cromoglycate (P less than 0.001) or placebo (P less than 0.01). Levocabastine was also superior in reducing subjective itch in the eyes. Determination of the ATD can be used as a relatively quick assessment of drugs intended for the treatment of allergic conjunctivitis.
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PMID:Topical levocabastine protects better than sodium cromoglycate and placebo in conjunctival provocation tests. 196 26

Giant papillary conjunctivitis (GPC) is largely a soft contact lens-related syndrome, characterized by the formation of giant papillae on the upper tarsal conjunctiva, itching, excess mucus, erythema, and contact lens intolerance. In response to the suggestion that GPC occurs more frequently in atopic individuals, a retrospective study was designed in order to determine the months in which patients were diagnosed with GPC during 1987 and 1988. Personal histories of allergy were also recorded for these patients, and compared to an age- and sex-matched control group. Significant peaks in the number of patients diagnosed with GPC occurred in the spring, and especially in late summer/early fall of both years. In addition, the GPC patients reported significantly more overall allergies than did the control group. However, a breakdown of the individual allergy data revealed that only allergies to contact lens solutions, specifically thimerosal, were significantly higher in the GPC group. Reported allergies to medications and pollen were also elevated in the GPC patients, but not significantly. The seasonal onset of GPC diagnoses in 1987 and 1988, and the increase in reported allergies within the GPC group, suggests a strong association between atopy and the development of GPC.
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PMID:Association of giant papillary conjunctivitis with seasonal allergies. 232 Mar 63

Antihistamines act by competing with histamine for H1 or H2 histamine receptors on cell membranes. In addition, most of the common antihistamines bind other receptors and thus exert other pharmacologic actions. For all practical purposes, mast cells and basophils are the main physiologic sources of histamine, and the primary usefulness of antihistamines is in diseases characterized by excessive production and release of histamine by these two cell types. Experimental models have proven useful for evaluating antihistamine compounds in humans. In these model systems, a test drug may be employed to block one or more of the known effects of exogenously administered histamine or a histamine agonist. Or the release of endogenous histamine may be brought about in a controlled fashion by agents such as allergens, opiates, or compound 48/80, and the drug's effects on this process may then be measured. In the case of the central nervous system, unfortunately, such models are not available and other means of evaluation must be devised. The dose response and duration of action of orally administered antihistamines can be determined in a simple skin model by their blocking of the wheal and erythema (flare) resulting from an intradermal challenge with histamine, an allergen, or compound 48/80. Antihistamines can also be evaluated in urticaria induced by scratching or cold. Itching that commonly follows injection of histamine or an allergen into the skin is also inhibited by this class of drugs. Most of the commonly used antihistamines are effective in these models, which form the basis for evaluating antihistamines in the treatment of skin diseases. In the nose and conjunctiva, other model strategies are used.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Clinical pharmacodynamics of antihistamines. 289 49

Levocabastine is a new, highly potent, and specific H1 antagonist. The effects of this drug, administered topically, were evaluated in a conjunctival provocation test (CPT) with allergens. CPT was performed by the instillation of one drop of allergen at increasing concentrations in the inferior conjunctival sac of each eye, alternatively, and stopped when both itching and redness of the conjunctiva were present. The concentration of allergen at this step was considered as the reaction threshold. Eleven patients, allergic to grass pollen, underwent, in winter, a first CPT without pretreatment (screening test); the CPT was then repeated twice after a 24-hour treatment, once, with a placebo, and once, with levocabastine (one drop twice a day, 0.5 mg/ml), administered in a double-blind fashion and in random order. The minimal interval between the two tests was 1 week. There was no significant difference between the thresholds determined in the two CPTs performed without medication (screening test and placebo), whereas the threshold was significantly increased (p less than 0.001) after pretreatment with levocabastine. Individually, the threshold increased in 10/11 patients (p less than 0.01). Levocabastine prevented both redness and itching. A late allergic reaction was observed by the patient in 6/11 CPTs performed after placebo treatment and 8/11 after levocabastine treatment. We conclude that, in this model of allergic conjunctivitis, levocabastine increased the conjunctival tolerance to an allergen. Further studies should help to determine the true place of this H1 antagonist in the treatment of allergic conjunctivitis.
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PMID:Effect of levocabastine, a new H1 antagonist, in a conjunctival provocation test with allergens. 290 14

This study was performed to investigate the inflammatory changes occurring in the human conjunctiva at different time periods after allergen provocation. Twenty-three ryegrass-sensitive patients with allergic conjunctivitis (19 with hayfever and four with vernal conjunctivitis) were challenged by topical administration of ryegrass antigen to the eye. Allergen concentrations were increased in increments until an immediate ocular allergic reaction was elicited. Numbers of various inflammatory cells (neutrophils, eosinophils, lymphocytes, and monocytes) found in conjunctival scrapings were quantified and correlated with the clinical profile, total serum IgE, and serum IgE to Rye I antigen. Twenty minutes after some level of antigen topical challenge to the eye, all patients had ocular redness, tearing, and itching. Compared with findings in seven control subjects, significant inflammatory cells were found in the conjunctival scrapings of patients before challenge (p less than 0.05) and 20 minutes (p less than 0.001) and 6 hours (p less than 0.002) after effective challenge. Significant increases in neutrophils of patients occurred after 20 minutes (p less than 0.001), and in eosinophils at 6 hours (p less than 0.005), compared with values of control subjects. When each case was evaluated individually, nine of the 23 patients had highly evident inflammatory changes 6 hours after allergen provocation. The levels of total serum IgE and serum IgE to Rye I antigen of these nine patients did not differ significantly from the other patients in the study. Our data provide the first evidence in humans that significant inflammatory changes in conjunctival scrapings are present long after allergen exposure has ended.
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PMID:Inflammatory changes in conjunctival scrapings after allergen provocation in humans. 229 2

The epidemiological and clinical features of primary herpes simplex virus ocular infection in 108 patients were studied. Of these, 69 (64%) were aged 15 or over and only eight (7%) were under the age of 5. Associated upper respiratory tract infection was found in 38 (35%) patients and systemic disorders such as mild malaise, fever, and aching in 34 (31%) patients. Common symptoms were redness, watering, discharge, itching, irritation, and lid swelling, whereas pain, photophobia, lid vesicles and ulcers, and blurred vision were less frequent. The major signs consisted of vesicles and ulcers on the lids, papillary responses which were more severe in the upper lid conjunctiva, follicles which were more common in the lower lid conjunctiva, fine and coarse epithelial punctate keratitis, and subepithelial punctate keratitis. Dendritic ulcers and disciform keratitis were found in 16 (15%) and two (2%) patients respectively. The clinical forms of primary herpes simplex virus ocular infection varied. Moderate or severe disease was observed in 41 (38%) and 16 (15%) patients respectively. In eight (7%) patients the disease presented as an acute follicular conjunctivitis without characteristic lid or corneal lesions. A chronic blepharoconjunctivitis which lasted for months developed in 16 (15%) patients. The epidemiological and clinical features in our patients were compared with features of the disease reported previously.
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PMID:Epidemiological and clinical features of primary herpes simplex virus ocular infection. 396 25


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