RESUMEN
BACKGROUND: Atopic keratoconjunctivitis (AKC) is a chronic eye disease with periods of exacerbations. Many patients experience no obvious seasonal variation, although a majority of patients are allergic to common airborne allergens. OBJECTIVE: To investigate the allergic reaction, to conjunctival provocation with airborne allergens, in patients with AKC. METHODS: Eleven patients with AKC and birch and/or grass pollen allergy participated in the study, which was performed outside the pollen season. Five patients with seasonal allergic conjunctivitis (SAC) and five healthy subjects were included for validation purposes. The challenge was performed in one eye with the allergen, to which the patient was reactive, and with dilution buffer in the other eye. Signs and symptoms from both eyes were graded at baseline and at 10 min, 8 and 48 h after provocation. Tear fluid was collected from both eyes for cytokine analyses at baseline and at 8 and 48 h. RESULTS: A significant change in clinical symptoms and signs, (redness and chemosis) was evident 10 min after provocation compared with baseline (P = 0.005) and compared with the unprovoked eye (P = 0.005) in AKC subjects. These parameters were normalized after 8 and 48 h. A significant increase for IFN-γ (P = 0.021) and IL-6 (P = 0.015), and a near significant increase for IL-10 (P = 0.066) were seen in the tear fluid of the challenged eye at 48 h after provocation vs. baseline and vs. the control eye for IFN-γ (P = 0.005), IL-6 (P = 0.028) and IL-10 (P = 0.008) in AKC subjects. CONCLUSION AND CLINICAL RELEVANCE: In this single dose allergen provocation study, AKC patients responded with a typical IgE-mediated allergic reaction. An increase in cytokines at 48 h after the challenge was demonstrated and might, with further studies, give us a better understanding of the nature of inflammation in AKC.
Asunto(s)
Alérgenos/administración & dosificación , Betula/inmunología , Conjuntiva/inmunología , Conjuntivitis Alérgica/fisiopatología , Queratoconjuntivitis/fisiopatología , Phleum/inmunología , Adulto , Anciano , Contaminación del Aire/efectos adversos , Alérgenos/efectos adversos , Alérgenos/inmunología , Conjuntivitis Alérgica/inmunología , Citocinas/biosíntesis , Citocinas/inmunología , Femenino , Humanos , Inmunoglobulina E/sangre , Inflamación/inmunología , Inflamación/fisiopatología , Queratoconjuntivitis/inmunología , Masculino , Persona de Mediana Edad , Polen/inmunología , Lágrimas/inmunologíaRESUMEN
It is widely accepted that nonspecific tissue reactivity is a distinct pathophysiological hallmark of allergic diseases, influenced by genetic and environmental factors different from those involved in causing sensitization and allergen response of target organs. This consensus document aims at reviewing procedures currently used for nonspecific provocation of the bronchi, nose and eye and for measuring their responsiveness to nonspecific stimuli.
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Hiperreactividad Bronquial/fisiopatología , Pruebas de Provocación Bronquial/métodos , Hipersensibilidad/fisiopatología , Músculo Liso/fisiopatología , Pruebas de Provocación Nasal/métodos , HumanosRESUMEN
AIMS: The main objective of this explorative study was to evaluate if tacrolimus ointment could be safer than corticosteroid ointment, with special reference to the intraocular pressure in the treatment of eyelid eczema in patients with atopic keratoconjunctivitis (AKC). Secondary aims were to compare the effects of the treatments on eyelid eczema and their potential impact on ocular surface inflammation. METHODS: Tacrolimus 0.1% ointment and clobetasone butyrate 0.05% ointment were compared in a double-masked explorative crossover study. In total, 25 AKC patients were included. Each ointment was applied twice daily for 3 weeks, with 2 weeks of washout before, between, and after treatments. Efficacy was determined by eye examination and the patients' own symptom scoring. Cytology and cytokine measurements were performed on tear samples. Safety parameters were intraocular pressure, presence of bacteria and fungi, and the patients' reports of adverse events. The validity of the crossover design was explored with analysis of variance, and the effect of each medication was calculated with paired t-test and Wilcoxon paired test. RESULTS: A total of 20 patients completed the study. Both treatments were effective in reducing signs and symptoms of eyelid eczema, with a near superior benefit for tacrolimus in terms of eczema (total skin score) signs (P=0.05). No serious adverse events occurred and interestingly, intraocular pressure was not evidently affected by either treatment. CONCLUSION: Tacrolimus 0.1% ointment is a promising alternative therapy for eyelid eczema in AKC patients. Long-term studies are needed to further determine the value of tacrolimus in this patient group.
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Blefaritis/tratamiento farmacológico , Dermatitis Atópica/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Queratoconjuntivitis/complicaciones , Tacrolimus/uso terapéutico , Adolescente , Adulto , Anciano , Anticuerpos Antibacterianos/sangre , Biomarcadores/metabolismo , Blefaritis/complicaciones , Clobetasol/efectos adversos , Clobetasol/análogos & derivados , Clobetasol/uso terapéutico , Estudios Cruzados , Citocinas/metabolismo , Dermatitis Atópica/complicaciones , Párpados/microbiología , Femenino , Glucocorticoides/efectos adversos , Humanos , Inmunosupresores/uso terapéutico , Mediadores de Inflamación/metabolismo , Presión Intraocular/efectos de los fármacos , Masculino , Persona de Mediana Edad , Pomadas , Tacrolimus/efectos adversos , Lágrimas/metabolismo , Resultado del TratamientoRESUMEN
To gain further knowledge of possible risk factors for the development of postoperative endophthalmitis (POE) following cataract surgery, a single-centre retrospective case-control study was conducted for 1994-2000. In total, 46292 cataract procedures were performed during the study period. Sixty cases of POE were noted and 240 control cases were selected at random. Parameters pertaining to patient history and to peri-operative technique and complications were analysed. The relative risk of POE was calculated using univariate analyses and multi-variate forward stepwise logistic regression. In the logistic regression analyses, three statistically significant parameters were found. The use of intracameral prophylaxis with cefuroxime as opposed to topical treatment alone, and performing phaco-emulsification instead of extra- or intracapsular cataract extraction appeared to be protective against POE. Silicone intra-ocular lenses carried a higher risk than heparin surface modified poly (methyl methacrylate) implants. In summary, the important finding of this study was the protective effect against POE of intracameral prophylaxis with cefuroxime compared with topical anti-infectives alone.
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Extracción de Catarata , Endoftalmitis/etiología , Complicaciones Posoperatorias/etiología , Anciano , Profilaxis Antibiótica/métodos , Estudios de Casos y Controles , Cefuroxima/administración & dosificación , Endoftalmitis/epidemiología , Endoftalmitis/prevención & control , Femenino , Humanos , Implantación de Lentes Intraoculares/métodos , Masculino , Facoemulsificación , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Factores de RiesgoRESUMEN
BACKGROUND: The cause of the chronic inflammation in atopic keratoconjunctivitis (AKC), the ocular manifestation of atopic eczema/dermatitis syndrome, is largely unknown. OBJECTIVE: To investigate the possibility that microorganisms may be important in the inflammatory activity in AKC. METHODS: Fifteen patients with AKC participated in the study. The presence of aerobic bacteria and fungi was related to the severity of clinical signs, the numbers of inflammatory cells in tears and conjunctival biopsies, and the concentration of various cytokines in tears. In addition, serological evidence for IgE sensitization to Staphylococcus aureus B antigen and Malassezia sympodialis antigen was investigated. Twelve healthy subjects were included for control purposes. RESULTS: The patients exhibited moderate clinical signs of AKC. No relation was found between the severity of AKC and the presence of microorganisms, despite the fact that S. aureus was frequently isolated. AKC patients showed significantly higher levels of IFN-gamma, TNF-alpha (tumour necrosis factor-alpha), IL-2, IL-4, IL-5 and IL-10 than controls. An association was found between conjunctival signs and the levels of all cytokines except IL-5. CONCLUSION: We found no evidence to suggest that periocular and ocular microcolonization are related to inflammatory parameters in AKC. However, confirmation of the present results in a longitudinal study with repeated clinical examinations and samplings in the same individual is required before the contribution of S. aureus to on-going inflammation in AKC can be dismissed.
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Conjuntivitis Alérgica/microbiología , Infecciones del Ojo/complicaciones , Adulto , Anciano , Antígenos Bacterianos/sangre , Antígenos Fúngicos/sangre , Estudios de Casos y Controles , Conjuntiva/inmunología , Conjuntiva/microbiología , Conjuntivitis Alérgica/inmunología , Infecciones del Ojo/inmunología , Infecciones Bacterianas del Ojo/complicaciones , Infecciones Bacterianas del Ojo/inmunología , Infecciones Fúngicas del Ojo/complicaciones , Infecciones Fúngicas del Ojo/inmunología , Femenino , Humanos , Inmunoglobulina E/sangre , Interferón gamma/análisis , Interleucinas/análisis , Masculino , Persona de Mediana Edad , Staphylococcus aureus/inmunología , Lágrimas/inmunología , Lágrimas/microbiología , Factor de Necrosis Tumoral alfa/análisisRESUMEN
Respiratory syncytial virus (RSV) and chlamydial infection may be pathogenetic factors in allergic diseases, perhaps also in ocular allergy. We analyzed the presence of RSV and chlamydial nucleic acids using reverse transcription (RT)-PCR and PCR, respectively, in conjunctival biopsies from patients with vernal keratoconjunctivitis (VKC) in order to determine whether these agents play a role in the maintenance of the disease. All biopsy samples were negative for both RSV (n = 15 for VKC and n = 10 for control subjects) and chlamydia (n = 8 for VKC and n = 7 for control subjects) homologous sequences. A direct association between RSV or chlamydial infection and ongoing inflammation in VKC could, therefore, not be confirmed.
Asunto(s)
Chlamydia trachomatis/aislamiento & purificación , Chlamydophila pneumoniae/aislamiento & purificación , Conjuntivitis Alérgica/virología , Virus Sincitiales Respiratorios/aislamiento & purificación , Adolescente , Biopsia , Niño , Preescolar , Chlamydia trachomatis/genética , Chlamydophila pneumoniae/genética , Conjuntiva/virología , ADN Bacteriano/análisis , ADN Viral/análisis , Femenino , Humanos , Masculino , ARN Viral/aislamiento & purificación , Virus Sincitiales Respiratorios/genética , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
PURPOSE: 1) To evaluate the effects on the conjunctival flora of gentamicin ophthalmic eye drops 0.3%, given four times in 45 minutes, and a conjunctival rinse with 10 ml chlorhexidine 0.05% solution. 2) To investigate retrospectively the rate of endophthalmitis after cataract operations when these antimicrobials were applied preoperatively. METHODS: Seventy-six patients undergoing standard phacoemulsification operations were enrolled in the experimental part of the study. Cultures were taken preoperatively, 5 minutes after prophylaxis with either chlorhexidine or gentamicin. To assess the combined effects of chlorhexidine and gentamicin, cultures were taken after the cataract operation. Hospital charts were reviewed for cases of endophthalmitis in 1994 and 1995, when this prophylactic protocol was used at the St Erik's cataract surgery department. RESULTS: The conjunctival microflora was significantly suppressed by chlorhexidine rinsing alone (p = 0.001), while no other significant anti-bacterial effects were observed with the experimental prophylaxis. The endophthalmitis rate was 32/12. 806 operations (0.25%). CONCLUSIONS: Topical rinsing with chlorhexidine solution suppresses conjunctival flora in the short term. Combined topical chlorhexidine and gentamicin prophylaxis does not eliminate postoperative endophthalmitis caused by gram-positive bacteria.
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Antibacterianos/uso terapéutico , Antiinfecciosos Locales/uso terapéutico , Profilaxis Antibiótica , Clorhexidina/uso terapéutico , Endoftalmitis/prevención & control , Gentamicinas/uso terapéutico , Facoemulsificación , Adulto , Anciano , Anciano de 80 o más Años , Conjuntiva/efectos de los fármacos , Conjuntiva/microbiología , Quimioterapia Combinada , Endoftalmitis/etiología , Endoftalmitis/microbiología , Femenino , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Soluciones Oftálmicas , Facoemulsificación/efectos adversos , Cuidados Preoperatorios , Estudios RetrospectivosRESUMEN
PURPOSE: To classify a cohort of 62 patients with vernal keratoconjunctivitis (VKC) in immunologic, functional, and epidemiological terms. METHODS: A retrospective chart review was conducted to establish the patients' ethnic origin and to ascertain the results of standard in vitro and in vivo testing for atopic allergy. The latter data were compared with tear Phadiatop, an allergy screening test, in 31 subjects. Further subgroup analyses included methacholine bronchial provocations, serum screening for chlamydial antibodies and epidemiological calculations of the observed prevalence of VKC in the Stockholm area in 1994. RESULTS: Thirty-seven subjects (59.7%) were sensitised to common allergens. No additional allergic subjects were diagnosed with the tear Phadiatop test. The serology for ocular chlamydial disease was negative. Only 6 out of 17 subjects displayed bronchial reactivity to methacholine of whom 4 had a history of asthma. VKC was clearly more common in individuals with an Asian and African origin. CONCLUSIONS: Sensitivity to allergens is a strong determinant for the disease but in a large proportion of the subjects this immunologic abnormality is absent. The varying prevalence of the condition in different ethnic groups indicates a genetic predisposing factor.
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Queratoconjuntivitis/epidemiología , Queratoconjuntivitis/inmunología , Estaciones del Año , Adolescente , África/etnología , Asia/etnología , Asma/complicaciones , Asma/fisiopatología , Biomarcadores/análisis , Hiperreactividad Bronquial/inducido químicamente , Broncoconstrictores , Niño , Preescolar , Chlamydia/inmunología , Etnicidad/estadística & datos numéricos , Femenino , Humanos , Hipersensibilidad/complicaciones , Hipersensibilidad/fisiopatología , Queratoconjuntivitis/etnología , Queratoconjuntivitis/fisiopatología , Masculino , Cloruro de Metacolina , Estudios Retrospectivos , Suecia/epidemiología , Suecia/etnologíaRESUMEN
OBJECTIVE: This study aimed to investigate the relationship between postoperative endophthalmitis and current changes in the cataract operative technique. DESIGN: A retrospective case-control study. PARTICIPANTS: The 22,091 cataract operations performed from 1990 through 1993 at St Eriks Hospital formed the basis for this investigation. In a random fashion, 220 control subjects were selected to be compared with the endophthalmitis cases. MAIN OUTCOME MEASURES: Numerous variables pertaining to the cataract extraction procedure and to the ocular and general health of patients with cataracts were analyzed regarding the development of postoperative intraocular infection. Patient age, presence of diabetes or immunosuppression, type of cataract extraction and intraocular lens (IOL), and intraoperative or postoperative complications were the principal variables assessed. RESULTS: Fifty-seven patients with endophthalmitis were diagnosed, resulting in an overall frequency of 0.26%. Immunosuppressive treatment (P = 0.019), wound abnormality (P = 0.03), and the use of IOLs without a heparinized surface (P = 0.0023) were the only significant risk factors found in a logistic regression model. CONCLUSIONS: The results suggest that cataract operating practice may alter the risk for endophthalmitis in that implanting a heparinized IOL and creating a tight section both seem to provide protection against this dreaded complication. Regarding patient history, an increased susceptibility was found among subjects treated with immunosuppressants. Designing a prophylactic protocol that protects against endophthalmitis more efficiently than did the study prophylaxis of 20 mg of subconjunctival gentamicin, is important not only for this patient subgroup but also for the cataract operated population at large.
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Extracción de Catarata/efectos adversos , Extracción de Catarata/métodos , Endoftalmitis/etiología , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Materiales Biocompatibles Revestidos , Endoftalmitis/diagnóstico , Endoftalmitis/tratamiento farmacológico , Femenino , Gentamicinas/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Complicaciones Intraoperatorias , Implantación de Lentes Intraoculares , Lentes Intraoculares , Masculino , Complicaciones Posoperatorias , Distribución Aleatoria , Estudios Retrospectivos , Factores de RiesgoRESUMEN
BACKGROUND: The appearance of eosinophils is a hallmark sign of the allergic late-phase response (LPR). Eosinophil cationic protein (ECP), a readily measurable product released from activated eosinophils, has so far not been evaluated in the ocular LPR. OBJECTIVE: Two sets of trials were performed in order to investigate changes of local and systemic eosinophil activity and their possible link with symptoms and hyperreactivity in the allergic LPR in the eye. METHODS: In the first experiment, ECP was analysed in tears and serum and the clinical reaction was evaluated during a 72-h time-course after a single, high-dose allergen challenge out of season in one eye of 15 pollen-sensitized volunteers. In a second experiment, the hypothesis of an increased clinical response to an allergen challenge in an eye that had been provoked with allergen 48 h previously was tested in nine sensitized individuals. RESULTS: In the first experiment, symptoms at 10 min and 2, 4, 6, 8 and 24 h significantly exceeded base line scores of the challenged eyes. Tear ECP was significantly elevated in challenged eyes compared to contralateral eyes at 6, 8 and 24 h. In addition, symptoms and ECP release correlated significantly at the 24-h evaluation. Serum ECP remained unchanged throughout the study period. In the second experiment, conjunctival hyperreactivity 48 h after an allergen challenge was not confirmed. CONCLUSION: ECP secretion occurs in the experimental ocular LPR and is in part associated with the magnitude of the clinical reaction, which suggests a truly pathogenic role of the activated eosinophil in pollen-induced allergic conjunctivitis.
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Alérgenos/administración & dosificación , Proteínas Sanguíneas/metabolismo , Eosinófilos/metabolismo , Ribonucleasas , Lágrimas/inmunología , Administración Tópica , Adolescente , Adulto , Relación Dosis-Respuesta Inmunológica , Proteínas en los Gránulos del Eosinófilo , Eosinófilos/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Lágrimas/metabolismoRESUMEN
AIMS/BACKGROUND--Eosinophil cationic protein (ECP) is a quantifiable product secreted by activated eosinophils. The aim of this study was to assess the degree of eosinophil activity in different clinical stages of various forms of allergic conjunctivitis. METHODS--Tears were collected in glass capillary tubes from 14 subjects with seasonal allergic conjunctivitis (SAC), 23 subjects with vernal keratoconjunctivitis (VKC), 16 subjects with atopic keratoconjunctivitis (AKC), 10 subjects with giant papillary conjunctivitis (GPC), and 16 healthy control subjects. The samples were analysed in duplicate with a radio-immunoassay for ECP. RESULTS--Statistically significant differences were evident between healthy controls and allergic subjects (p < 0.001). Subjects with AKC and VKC had significantly higher tear ECP values than subjects with GPC and SAC. In addition, there was a significant correlation between ECP values and disease severity in all disorders. CONCLUSION--The data suggest a particular pathogenic role of the eosinophil in VKC and AKC, and a less pronounced but still important eosinophil involvement in the disease processes of GPC and SAC.
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Proteínas Sanguíneas/análisis , Conjuntivitis Alérgica/metabolismo , Ribonucleasas , Lágrimas/química , Adolescente , Adulto , Anciano , Proteínas Sanguíneas/metabolismo , Estudios de Casos y Controles , Niño , Preescolar , Conjuntivitis Alérgica/inmunología , Proteínas en los Gránulos del Eosinófilo , Femenino , Humanos , Masculino , Persona de Mediana Edad , RadioinmunoensayoRESUMEN
BACKGROUND: Vernal keratoconjunctivitis (VKC) often is associated with atopy but a considerable part of the patients lack evidence of specific hypersensitivity. An immunocytochemical study was undertaken with the aim of detecting possible differences in the tissue inflammatory response between atopic and nonatopic subjects with VKC. METHODS: Conjunctival biopsy specimens from six atopic and three nonatopic subjects with VKC (age range, 7-17 years) and eight healthy control subjects (age range, 3-15 years) were analyzed with a panel of monoclonal and polyclonal antibodies. RESULTS: No distinct differences in cell counts between atopic and nonatopic subjects with VKC were observed. Vernal keratoconjunctivitis specimens as a whole showed higher counts than control specimens for CD3+, CD4+, HLA-DR+, CD38+, EG2+, CD68+, IgE+, FC epsilon RI+, IgA+, IgG+, and IgM+ cells in the substantia propria; and for CD1a+, IgE+, and EG2+ cells in the epithelium. CONCLUSIONS: Because the number of cells expressing CD4, EG2, IgE, and the high-affinity receptor for IgE, all of which are considered relevant in infiltrates of allergic conditions, were similar in atopic and nonatopic subjects, the authors conclude that the role of allergen-specific IgE sensitization in the pathogenesis of VKC remains unclear.
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Conjuntivitis Alérgica/patología , Hipersensibilidad Inmediata/patología , Inmunoglobulina E/análisis , Receptores de IgE/análisis , Ribonucleasas , Adolescente , Anticuerpos Monoclonales , Antígenos CD/análisis , Biomarcadores/análisis , Proteínas Sanguíneas/análisis , Niño , Preescolar , Conjuntiva/química , Conjuntiva/patología , Conjuntivitis Alérgica/complicaciones , Conjuntivitis Alérgica/inmunología , Proteínas en los Gránulos del Eosinófilo , Femenino , Humanos , Hipersensibilidad Inmediata/complicaciones , Hipersensibilidad Inmediata/inmunología , Inmunohistoquímica , Recuento de Leucocitos , MasculinoRESUMEN
All cases of contact lens induced keratitis (epithelial defects with an underlying infiltrate or ulcer) among cosmetic wearers in Sweden were collected in a 3-month prospective study and analyzed for risk factors in relation to lens type and wear schedule. Every ophthalmologist in Sweden was invited to participate and 100% responded. Viral cases were excluded. The number of lens wearers in Sweden, subdivided by lens type and wear schedule, was obtained in a parallel 3-month study among 71% of the lens fitters, who counted all their wearers, recording lens type and wear schedule as well as revisit and replacement schedules. The annualized incidence per 10,000 wearers was 1.48 for daily wear of rigid gas permeable lenses, 2.16 for daily wear and 10.00 for extended wear of disposable soft lenses, and 2.17 for daily wear and 13.33 for extended wear of conventional soft lenses. Thus, extended wear was associated with a significantly (P < 0.01-0.001) higher (5-6 times) risk of keratitis than daily wear. There were no other significant differences between the incidence figures. The Swedish incidence figures were approximately half as high as those reported in the U.S. Of the lesions, only 12% were located within the pupillary area and only 8% were corneal ulcers. Only three patients (12%) suffered a decrease in visual acuity. Severe keratitis was significantly (P < 0.01) more common among conventional soft lens wearers (accounting for all ulcers, all lesions within the pupillary area, and all decreases in visual acuity) than among wearers of disposable lenses.
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Lentes de Contacto/efectos adversos , Úlcera de la Córnea/etiología , Adulto , Lentes de Contacto/estadística & datos numéricos , Úlcera de la Córnea/epidemiología , Femenino , Humanos , Incidencia , Masculino , Estudios Prospectivos , Suecia/epidemiología , Estados Unidos/epidemiología , Agudeza VisualRESUMEN
All hospitalized cases of contact lens induced keratitis with stromal involvement among cosmetic wearers in Sweden over a 3-year period were reviewed for risk factors in relation to lens type and wear schedule. Information on every case was obtained from ophthalmology departments. Lens type and wear schedule were identified. The number of lens wearers, subdivided by lens type and wear schedule, was obtained from a study by the Swedish Contact Lens Association. Annual incidence figures were then calculated as expressions of risk factors. There were 30.7 cases per year, on average, of hospitalized lens induced keratitis in Sweden. The annual incidence per 10,000 wearers was 0.51 for daily wear and 3.12 for extended wear of conventional soft lenses, 0.16 for daily wear and 4.17 for extended wear of disposable soft lenses, and 1.21 for daily wear of rigid gas permeable lenses. It may be concluded that daily wear of disposable lenses was associated with significantly (P < 0.05-0.01) less risk of hospitalized keratitis than daily wear of the other lens types. Extended wear of conventional and disposable soft lenses showed a significantly (P < 0.01-0.001) higher risk of hospitalized keratitis than daily wear. However, the two extended wear groups did not differ significantly (P > 0.2). Microbial keratitis was significantly (P < 0.001) more common than sterile (no growth of microbes) keratitis among conventional soft lens wearers, whereas the opposite was true (P < 0.05) among disposable lens wearers.