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Peter C Donshik - One of the best experts on this subject based on the ideXlab platform.
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Giant Papillary Conjunctivitis
Current Opinion in Allergy and Clinical Immunology, 2008Co-Authors: William H Elhers, Peter C DonshikAbstract:Purpose of review Despite shorter replacement intervals and new lens materials, giant Papillary Conjunctivitis still limits the ability of some patients to wear contact lenses. Recent findings Recent research has elucidated many new mediators of inflammation. The presence of chemokines and cytokines such as IL-8, IL-6, IL-11, macrophage inflammatory protein-8, tissue inhibitor of metalloproteinases-2 macrophage-colony stimulating factor and monokine-induced gamma interferon, eotaxin, pulmonary and activation-regulated CC chemokines have been shown to be elevated in patients with giant Papillary Conjunctivitis. In addition, M cells and B lymphocytes have been hypothesized to play a role in the pathogenesis of giant Papillary Conjunctivitis. The pathophysiology of giant Papillary Conjunctivitis is complicated with both immune and mechanical mechanisms playing a role in the development of this condition; understanding these mechanisms is important in both treatment and prevention of giant Papillary Conjunctivitis.
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giant Papillary Conjunctivitis
Current Opinion in Allergy and Clinical Immunology, 2008Co-Authors: William H Elhers, Peter C DonshikAbstract:Purpose of reviewDespite shorter replacement intervals and new lens materials, giant Papillary Conjunctivitis still limits the ability of some patients to wear contact lenses.Recent findingsRecent research has elucidated many new mediators of inflammation. The presence of chemokines and cytokines su
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contact lens chemistry and giant Papillary Conjunctivitis
Eye & Contact Lens-science and Clinical Practice, 2003Co-Authors: Peter C DonshikAbstract:Objective. To review the relationship between contact lens chemistry and the occurrence of giant Papillary Conjunctivitis (GPC). Design. A review of the literature. Results. GPC can occur with any type of contact lenses. The coating on the lens and the contact lens trauma to the conjunctiva are probable factors. Changing the polymer of the contact lens that a patient with GPC wears can decrease the chance of the condition recurring. Also, replacing a soft contact lens at intervals of less than 3 weeks, rather than 4 or more weeks, significantly reduces the chance of developing GPC. GPC can occur with high Dk silicone contact lenses. Two forms of GPC have been reported: a generalized form similar to that seen with conventional soft contact lenses and a localized form in which the papillae are confined to one or two areas of the tarsal conjunctiva, near the lid margin. Conclusion. Contact lens chemistry plays a role in the development of GPC; however, other factors such as edge design, surface properties, fitting characteristics, and replacement cycle are also important variables in the pathophysiology of GPC.
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giant Papillary Conjunctivitis in frequent replacement contact lens wearers a retrospective study
American Journal of Ophthalmology, 2000Co-Authors: Peter C Donshik, A D PorazinskiAbstract:Abstract PURPOSE: A retrospective study was done of 47 patients who wore frequent-replacement contact lenses on a daily basis and replaced them every 1 day to 12 weeks. The incidence of giant Papillary Conjunctivitis (GPC) was determined, and potential risk factors that may predispose frequent-replacement contact lens wearers to develop GPC were assessed. METHODS: The records of patients who were fitted with frequent-replacement contact lenses with no prior contact lens experience (September 1993 to February 1997) were reviewed. RESULTS: Forty-seven of 260 patients met the requirement for inclusion in this study. Ten (21.27%) of the patients developed GPC. The incidence varied according to how often the contact lenses were replaced. Incidence was 36% in patients who replaced their lenses at 4 weeks or longer and 4.5% in patients who replaced their lenses at less than 4 weeks. Lenses were coated more often in patients who replaced their lenses at 4 weeks or longer (pi = .23). A significantly greater number of patients in the GPC group incorporated enzyme into their contact lens care system (pi = .0004). A history of allergy was present, significantly more often in patients who developed GPC (pi = .012). There was no significant difference between the groups for age, sex, average daily wearing time, Food and Drug Administration classification of contact lens material, time in contact lenses from fitting to diagnosis or last follow-up period, or the parameters and fitting characteristics of the contact lenses. CONCLUSION: The frequency of contact lens replacement appears to be an important variable in development of GPC. Although frequent-replacement contact lenses do not eliminate GPC, patients on a 1-day to 3-week replacement cycle had a significantly lower risk of developing GPC than patients who replaced their lenses at longer intervals. Coating was present less often on lenses replaced every 1 day to 3 weeks. In patients who are at high risk for GPC, replacing lenses at intervals of 1 day to 2 weeks appears to offer a better strategy in avoiding GPC than incorporating enzymatic cleaning into their care system.
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giant Papillary Conjunctivitis in frequent replacement contact lens wearers a retrospective study
The CLAO journal : official publication of the Contact Lens Association of Ophthalmologists Inc, 1999Co-Authors: A D Porazinski, Peter C DonshikAbstract:Purpose: We conducted a retrospective study of 47 patients who wore frequent replacement contact lenses on a daily-wear basis to determine the incidence of giant Papillary Conjunctivitis (GPC) and to assess the potential riskfactors that may predispose frequent replacement contact lens wearers to develop GPC. Methods: We reviewed the records of patients with no prior contact lens experience who were fit with frequent replacement contact lenses from September 1993 to February 1997. Results: Forty-seven of 260 patients met the requirements for inclusion in the study. Ten (21.27%) patients had developed GPC. The incidence varied with the frequency of contact lens replacement. The contact lens replacement schedule ranged from 1 day to 12 weeks. In those patients replacing their contact lenses every 4 weeks or at a longer interval, the incidence of GPC was 36%, while for patients who replaced their lenses more frequently, the incidence was 4.5%. Coated contact lenses were also more common among patients who replaced their lenses at 4 weeks or longer (P = 0.23). A significantly greater number of patients in the GPC group incorporated enzymatic cleaning into their contact lens care system (P = .0004). A history of allergy was more prevalent in patients who developed GPC and was stastistically significant (P= .012). There was no significant difference found between the groups for age, gender, average daily wearing time, FDA classification of contact lens material, time in contact lenses from fitting to diagnosis or last follow-up period, or the parameters and fitting characteristics of the contact lenses. Conclusion: The frequency at which patients replace their contact lenses appears to be an important variable in developing GPC. Although frequent replacement contact lenses do not eliminate GPC, patients on a 1-day to 3-week replacement cycle had a significantly lower risk of developing GPC than patients who replaced their lenses at longer intervals. Lens coating was present less often on contact lenses replaced daily and up to 3 weeks. For patients who are at high risk for GPC, replacing lenses at intervals ranging of one day to two weeks appears to offer a better strategy for avoiding GPC than incorporating enzymatic cleaning into their lens care system.
Susan Lightman - One of the best experts on this subject based on the ideXlab platform.
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cytokine production and mrna expression by conjunctival t cell lines in chronic allergic eye disease
Clinical & Experimental Allergy, 1999Co-Authors: Vl Calder, Andrea Leonardi, Roger J Buckley, Susan Lightman, Antonio G Secchi, G Jolly, M Hingorani, P AdamsonAbstract:Background Activated CD4(+) T cells, mast cells and eosinophils are the main cytokine-producing cell-types infiltrating the conjunctiva during chronic allergic eye diseases. Interactions between these cells are thought to play an important immunopathogenic role in these disorders (giant Papillary Conjunctivitis; vernal keratoConjunctivitis; atopic keratoConjunctivitis).Objective The objective was to compare the cytokine profiles of conjunctival T-cell lines from patients with different forms of chronic allergic eye disease.Methods T cells were isolated from conjunctival biopsies and non-specifically expanded into lines. The lines were immunophenotyped by flow cytometry. Cytokine production was quantified by immunoassays and more sensitive molecular techniques were used to investigate cytokine mRNA expression to identify the presence of interleukin (IL)-2, IL-4 and interferon (IFN)-gamma transcripts.Results Following four to six rounds of stimulation, the conjunctival T-cell populations were CD3(+) (> 93%), with variable levels of CD4 and CD8 expression. All were HLA-DR+ (> 80%) with some HLA-DQ expression. Conjunctival T-cell lines from atopic keratoConjunctivitis produced selective increases in LFN-gamma, IL-10 and IL-13 (P<0.01), those from vernal keratoConjunctivitis produced increased IL-5 (P<0.01) whereas T-cell lines from giant Papillary Conjunctivitis produced only low levels of cytokines. IL-4 was only detected at the mRNA level and was expressed in four out of five T-cell lines in the vernal keratoConjunctivitis group. In contrast there was moderate to strong expression of IFN-gamma in five out of six T-cell lines in atopic keratoConjunctivitis.Conclusion Different patterns of T-cell cytokine profiles were observed for each disease, with low-level, non-polarized cytokine production in giant Papillary Conjunctivitis, a TH2-like profile in vernal keratoConjunctivitis and a shift towards a TH1-like profile in atopic keratoConjunctivitis.
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phenotypic characterization of t cells infiltrating the conjunctiva in chronic allergic eye disease
The Journal of Allergy and Clinical Immunology, 1996Co-Authors: D Metz, Annette S Bacon, Stephen T Holgate, Susan LightmanAbstract:Abstract BACKGROUND: Chronic allergic Conjunctivitis comprises a spectrum of diseases including atopic keratoConjunctivitis, atopic blepharoConjunctivitis, vernal keratoConjunctivitis, and contact lens–associated giant Papillary Conjunctivitis. Each condition is characterized by a complex immunopathology with a mixed cellular infiltrate. Treatment with conventional mast cell stabilizers is often unsatisfactory, and therapy depends heavily on topical corticosteroids. OBJECTIVE: Recent evidence suggests that T lymphocytes play an important role in mediating the immunopathology seen in the chronic allergic response in the skin and the lungs. METHODS: We have therefore investigated the prevalence of T cells and their subsets in the different chronic allergic eye conditions by means of immunohistochemistry. RESULTS: We found significantly increased numbers of CD4 + , CD45RO + , and HLA-DR + T cells in the conjunctiva of patients with atopic and vernal keratoConjunctivitis and giant Papillary Conjunctivitis, with a corresponding upregulation of markers present on antigen presenting cells. CONCLUSIONS: These findings suggest that like allergic conditions in the skin and lungs, CD4 + memory T cells are involved in the regulation of the immunopathology of chronic allergic eye responses. Further characterization of these T cells will provide the information necessary for future immunotherapeutic interventions. (J ALLERGY CLIN IMMUNOL 1996;98:686-96.)
Murat Irkec - One of the best experts on this subject based on the ideXlab platform.
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immunohistochemical findings in prosthesis associated giant Papillary Conjunctivitis
Clinical and Experimental Ophthalmology, 2007Co-Authors: Banu Bozkurt, Murat Irkec, Ugur Erdener, Nalan Akyurek, Leyla MemisAbstract:Purpose: To identify functional subsets of inflammatory cells and expression of cytokines in the conjunctiva of patients with ocular prosthesis-associated giant Papillary Conjunctivitis (P-GPC). Methods: Specific immunohistochemical staining using monoclonal antibodies was performed on biopsy specimens obtained from superior tarsal conjunctiva of 18 patients with P-GPC. The prosthetic eyes were taken as the study group, whereas their fellow eyes were used as matched controls. Results: In normal conjunctiva, mast cells (MCs) were located only in the substantia propria (SP), whereas in P-GPC eyes MCs were also notable in the epithelium in five specimens. Tryptase-chymase-positive MCs (MCTC) were predominant both in P-GPC (79%) and in fellow (72%) eyes. MCTC, CD4+ lymphocyte, CD8+ lymphocyte and eosinophil numbers were higher in P-GPC specimens compared with the fellow eyes (P = 0.005, 0.074, 0.012 and 0.025, respectively). Eosinophils were detected in 58.8% of P-GPC specimens and 16.7% of control specimens (P = 0.053). The number of inflammatory cells expressing eotaxin and interleukin (IL)-4 was higher in P-GPC group (P = 0.050 and 0.048, respectively). Nine out of 17 giant Papillary Conjunctivitis specimens (52.9%) showed eotaxin and IL-4 immunoreactivity, which was considerably higher than the fellow eyes (16.7%) (P = 0.064). Conclusion: These findings suggest that P-GPC is an allergic disease of the eye associated with increased numbers of MC, eosinophils and lymphocytes in the conjunctiva and a remarkable expression of IL-4 and eotaxin both by the conjunctival epithelium and by the inflammatory cells in the SP.
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Tear eotaxin levels in giant Papillary Conjunctivitis associated with ocular prosthesis
Ocular immunology and inflammation, 2003Co-Authors: Ozge Sarac, Murat Irkec, Ugur Erdener, Yucel GungenAbstract:Purpose: To examine the role of eotaxin and eosinophil recruitment in the immunopathogenesis of ocular prosthesis-associated giant Papillary Conjunctivitis (GPC). Methods: The tear eotaxin level was measured in 68 eyes with GPC, the fellow eyes of the GPC patients, and 22 normal subjects, using an ELISA method. Upper tarsal conjunctival specimens harvested from 18 patients with GPC were examined by light microscopy. Results: There was no significant difference in tear eotaxin levels between patients with GPC and healthy subjects. In patients with chronic GPC, the tear eotaxin levels were significantly lower. These eyes also had decreased conjunctival cellularity and increased fibrosis in the substantia propria. Biopsy specimens showed infiltration of lymphocytes and mast cells, but no eosinophils were found. Conclusion: Eotaxin and eotaxin-mediated eosinophil recruitment do not seem to have a major role in the immunopathology of chronic GPC associated with an ocular prosthesis.
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role of tear inflammatory mediators in contact lens associated giant Papillary Conjunctivitis in soft contact lens wearers
Ocular Immunology and Inflammation, 1999Co-Authors: Murat Irkec, Mehmet Orhan, Ugur ErdenerAbstract:Contact lens-associated giant Papillary Conjunctivitis (CL-GPC) caused by mechanical and immune mechanisms is a significant problem resulting in contact lens intolerance and discontinuation of contact lens wear. In the present study, tear fluid leukotriene C4 (LTC4) level was evaluated in soft contact lens wearers with and without CL-GPC using ELISA. Statistical analysis showed no significant difference in tear fluid LTC4 between contact lens wearers without GPC and normal controls (p>0.05), but a significant increase in tear LTC4 level in CL-GPC patients (p<0.05). On the basis of this finding, it might be possible to explain redness, conjunctival edema, increased mucoid secretion, and Papillary changes by the effect of LTC4 on eye tissues. Effective treatment of CL-GPC might be possible in the future by employing inhibitors of leukotriene synthesis and action.
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Effect of lodoxamide on tear leukotriene levels in giant Papillary Conjunctivitis associated with ocular prosthesis
Ocular immunology and inflammation, 1998Co-Authors: Ahmet Akman, Mehmet Orhan, Murat Irkec, Ugur ErdenerAbstract:Leukotrienes have been shown to play a role in the patho-genesis of ocular inflammatory and allergic reactions like vernal kerato-Conjunctivitis and contact lens-associated giant Papillary Conjunctivitis. This study was designed to determine leukotriene B4 (LTB4) and leukotriene C4 (LTC4) levels in the tears of patients with ocular prosthesis-associated giant Papillary Conjunctivitis (OP-GPC) and to evaluate the effects of lodoxamide 0.1% on tear LTB4 and LTC4 levels of OP-GPC patients. Tear LTB4 and LTC4 levels were determined by an ELISA technique in the tears of ten OP-GPC patients before and after treatment with lodoxamide 0.1% for one month. The results were compared with that of ten healthy control subjects. The mean tear LTB4 and LTC4 levels of the OP-GPC patients were significantly higher than those of the control group. After treatment with lodoxamide 0.1%, tear LTB4 and LTC4 levels of the OP-GPC patients decreased significantly. This is the first report of elevated LTB4 and LTC4 levels in tears ...
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tear ltc4 levels in patients with subclinical contact lens related giant Papillary Conjunctivitis
The CLAO journal : official publication of the Contact Lens Association of Ophthalmologists Inc, 1995Co-Authors: T Sengor, Murat Irkec, Y Gulen, M Taseli, H ErkerAbstract:We determined the tear levels of LTC 4 in contact lens wearers who had minimal irritative symptoms and signs suggesting subclinical conjunctival abnormalities and the possible development of giant Papillary Conjunctivitis (GPC). We examined 25 patients wearing rigid gas permeable lenses. Ten of the contact lens wearers had minimal irritative symptoms and nonspecific Papillary hypertrophy, and 15 patients had no symptoms. We included eight controls chosen from the same age group who were not contact lens wearers and who had normal conjunctiva. Tear samples were examined through the ELISA technique. Elevated levels of LTC 4 were found in the tears of symptomatic patients (525.50 ± 202 pg/mL) compared with tears of asymptomatic contact lens wearers (52.6 ± 10.2 pg/mL) and the control group (75 ± 8.4 pg/mL) (P< 0.001). Two patients in the first group developed G PC in the course of their follow-up. The results of this study indicate that detecting tear LTC 4 levels in contact lens wearers can give useful information regarding the presence of contact lens related subclinical inflammation and subclinical GPC.
Mark D P Willcox - One of the best experts on this subject based on the ideXlab platform.
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ige antibody on worn highly oxygen permeable silicone hydrogel contact lenses from patients with contact lens induced Papillary Conjunctivitis clpc
Eye & Contact Lens-science and Clinical Practice, 2008Co-Authors: Zhenjun Zhao, Cheryl Skotnitsky, Padmaja Sankaridurg, Mark D P WillcoxAbstract:Purpose To investigate whether the level of IgE is increased in the eyes of patients during general contact lens-induced Papillary Conjunctivitis (CLPC) events, which involve enlarged papillae across the entire palpebral conjunctiva, or local CLPC events, in which papillae are confined to one or two parts of the area. Methods Worn contact lenses were collected and soaked in phosphate-buffered saline. The levels of eluted IgE and IgE retained on contact lenses were detected by enzyme-linked immunosorbent assay. Results IgE was detected in 6 of 12 cases of general CLPC, 8 of 21 cases of local CLPC, and none of 14 control contact lenses. The average level of eluted IgE was 0.54 +/- 1.06 IU/contact lens, 0.28 +/- 0.54 IU/contact lens, and 0.04 +/- 0.06 IU/contact lens for general CLPC, local CLPC, and the control group, respectively. The incidences of positive IgE were significantly higher in patients with CLPC (general and local) than in control subjects, but no statistical difference was found between general and local CLPC. Generally higher amounts of retained IgE were detected on contact lenses that had increased levels of eluted IgE. Contact lenses that were collected before or after a CLPC event did not show increased levels of IgE. Conclusions The level of IgE is increased in the eyes of some patients during an acute event of CLPC. The similar incidence of IgE-positive cases and levels of IgE from general and local CLPC contact lenses suggest that the conditions may share similar causal pathways.
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contact lens induced Papillary Conjunctivitis is associated with increased albumin deposits on extended wear hydrogel lenses
Advances in Experimental Medicine and Biology, 2002Co-Authors: Maxine E Tan, Padmaja Sankaridurg, Gulhan Demirci, Damon Pearce, Isabelle Jalbert, Mark D P WillcoxAbstract:Contact lens Papillary Conjunctivitis (CLPC) may be a combination of immunological and mechanical responses to contact lenses and their deposits, resulting in a hypersensitivity reaction.1 Enlarged papillae on the tarsal conjunctiva, redness, itching, increased mucus, and decreased contact lens tolerance are typical symptoms. 2 CLPC is a major reason for discontinuing contact lens wear; 3 however, the link between lens deposits, mechanical trauma, the immunological response and ultimate discontinuation of lens wear is still unclear. In view of the known immunological aspects of CLPC, our aim was to determine the levels of human serum albumin (HSA), secretory IgA (sIgA, a constitutive protein) and lactoferrin (a regulated protein) on extended wear contact lenses (EWCL).
John Howes - One of the best experts on this subject based on the ideXlab platform.
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a double masked placebo controlled evaluation of the efficacy and safety of loteprednol etabonate in the treatment of giant Papillary Conjunctivitis
American Journal of Ophthalmology, 1997Co-Authors: Mitchell H Friedlaender, John HowesAbstract:Purpose To evaluate the safety and effectiveness of loteprednol etabonate 0.5% ophthalmic suspension in reducing the ocular signs and symptoms accompanying contact lens-associated giant Papillary Conjunctivitis. Methods In a randomized, double-masked, placebo-controlled, parallel-group study conducted at 14 academic or private practice clinics, 223 adults with contact lens-associated giant Papillary Conjunctivitis received either loteprednol or the loteprednol vehicle (placebo), one drop, four times daily for 6 weeks. Papillae, itching, contact lens intolerance, other signs and symptoms of giant Papillary Conjunctivitis (0-to-3 or 0-to-4 grade scales), and intraocular pressure were measured. Results The proportion of patients treated with loteprednol who at final visit demonstrated an improvement in papillae of at least one grade (78%, 85/109) was significantly greater than the proportion of those treated with placebo (51%, 56/110; P = .001). A treatment difference favoring loteprednol was seen with improvement in itching (95% vs 81%, 104/109 vs 89/110; P P = .053). Eight of 109 patients (7%, all taking loteprednol) had an intraocular pressure increase of 10 mm Hg or more on at least one visit during treatment. After discontinuation of loteprednol, intraocular pressure returned to normal levels. Both treatments were well tolerated, and no serious unexpected treatment-related medical events were reported. Conclusions The rapid therapeutic response combined with the low incidence and transient nature of any intraocular pressure increase suggests that loteprednol is an appropriate treatment for giant Papillary Conjunctivitis.
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a double masked placebo controlled evaluation of the efficacy and safety of loteprednol etabonate in the treatment of giant Papillary Conjunctivitis
The CLAO journal : official publication of the Contact Lens Association of Ophthalmologists Inc, 1997Co-Authors: Penny A Asbell, John HowesAbstract:Purpose:To evaluate the safety and effectiveness of loteprednol etabonate 0.5% ophthalmic suspension (LE) for reducing the ocular signs and symptoms accompanying contact lens associated giant Papillary Conjunctivitis (GPC). We conducted a randomized, double-masked, placebo-controlled, parallel study at 11 U.S. academic or private practice clinics. Methods: Two hundred and twenty adults with contact lens associated GPC were enrolled in this study. Patient were treated with either LE or the loteprednol etabonate vehicle (placebo), q.i.d. for 6 weeks. Papillae, itching, lens intolerance, as well as other signs and symptoms of GPC (0 to 3 or 0 to 4 point severity scales), and intraocular pressure were measured. Results: The proportion of patients treated with LE demonstrating an improvement in papillae of at least one grade (75%) was significantly greater than the proportion of those treated with placebo (50%, P < 0.001). A treatment difference favoring LE was also seen with improvement in itching (92% vs. 76%, P= 0.001) and lens intolerance (84% vs. 66%, P= 0.002). Three patients (all on LE) had an intraocular pressure (IOP) elevation of 10 mm Hg or higher from baseline on at least one on-treatment visit. Cessation of therapy was required in one of these patients. Conclusions: Both treatments were well tolerated and no serious, unexpected, treatment-related medical events were reported. The rapid therapeutic response, combined with the low incidence, late development, and transient nature of any IOP elevation suggests that LE may be helpful in treating GPC.
