Demodex sp. as a Potential Cause of the Abandonment of Soft Contact Lenses by Their Existing Users.

Demodex mites may be a potential etiological factor in the development of various eye and skin disorders. The aim of the study was to investigate the presence of Demodex in the hair follicles of eyelashes and their potential influence on abandoning soft contact lenses which had been previously well tolerated by their users. A group of 62 users of contact lenses (28 with emerging discomfort and 34 without discomfort) were examined. There is a need to check the existence of a relationship between D. folliculorum or/and D. brevis infestation and the emergence of intolerance to the presence of soft contact lenses. The removed lashes were examined under light microscopy, applying standard parasitological methods if demodicosis is suspected. A positive result was assumed if at least one adult stage, larva, protonymph/nymph, or egg of D. folliculorum and/or D. brevis was present. A positive correlation was observed between the presence of Demodex and intolerance to contact lenses by their existing users (p < 0.05), and Demodex sp. infections were observed in 92.86% of patients with intolerance to contact lenses. Our results provide further evidence for the pathogenic role played by the mites in the development of eye diseases.

Ocular rhinosporidiosis presenting as recurrent chalazion.

Rhinosporidiosis, a granulomatous disease caused by Rhinosporidium seeberi, is widely prevalent in Sri Lanka and southern parts of India. Besides the eye, the lacrimal passage and nasal cavity are affected. The most common ocular involvement is a subconjunctival bleeding mass. Our case, a 9-year-old girl from a rural background with a history of pond water bathing, presented with a marginal chalazion involving the left lower lid. She had a history of chalazion involving the same site three months earlier which was managed by incision and curettage. A decision of surgical exploration was made and the evacuated mass was examined histologically showing evidence of rhinosporidiosis. This type of clinical presentation for ocular rhinosporidiosis (as recurrent chalazion) has not been reported earlier in the literature. This case emphasises that the clinicians from this part of the world must consider ocular rhinosporidiosis as differential diagnosis in cases with recurrent chalazion especially in a rural background with a habit of pond water bathing.

High prevalence of demodex brevis infestation in chalazia.

PURPOSE: To investigate the correlation between demodicosis and chalazia in patients with the latter. DESIGN: Prospective, observational, comparative study. METHODS: Forty-four adult and 47 pediatric patients with chalazia and 34 adult and 30 pediatric age- and sex-matched patients without chalazia treated at an institutional referral eye center were included. All 155 patients underwent lash sampling followed by microscopic identification and counting of Demodex mites. All 91 patients with chalazia underwent surgical removal, and among them, 74 were followed up for 18 ± 4.3 months after surgery. Statistical correlation between ocular demodicosis and chalazia and its postoperative recurrence was performed. RESULTS: Demodicosis was significantly more prevalent in chalazia patients than in control patients as a group (69.2% vs 20.3%) and when separated into pediatric (70.2% vs 13.3%) and adult (68.2% vs 26.5%) subgroups (all P < .001). Demodicosis was associated strongly with chalazia (odds ratio, 4.39; 95% confidence interval, 2.17 to 8.87; P < .001). D. brevis was significantly more prevalent (odds ratio, 18.21; 95% confidence interval, 2.22 to 149.74; P = .01) than D. folliculorum (odds ratio, 2.82; 95% confidence interval, 1.16 to 6.84, P = .02) in patients with chalazia. Patients with demodicosis tended to demonstrate recurrence (33.3% vs 10.3%; P = .02), especially in those with D. brevis (35.1% vs 13.5%; P = .03). CONCLUSIONS: There is a high prevalence of demodicosis, especially cases of caused by D. brevis, in adult and pediatric patients with chalazia, suggesting that ocular demodicosis is a risk factor for chalazia.

Ocular demodicidosis as a risk factor of adult recurrent chalazion.

PURPOSE: To report Demodex infestation in adult recurrent chalazion and its clinical response to weekly lid scrub with 50% tea tree oil (TTO) and daily lid scrub with tea tree shampoo. METHODS: This is a retrospective review of 30 adult patients (48 eyes) who presented with recurrent chalazion within 6 months after conventional treatment. Demodex was detected by random lash sampling and microscopic examination. Patients with confirmed ocular Demodex infestation were treated with weekly lid scrub with 50% TTO and daily lid scrub with tea tree shampoo. The study is limited by the lack of a control group. RESULTS: The mean age of patients was 39.1 ± 10.2 years (range 18-69). The mean follow-up of patients is 10.0 ± 3.0 months (range 6-24 months). Among 48 eyes with recurrent chalazion, Demodex mites were found in 35 (72.9%). Recurrent chalazion was found to be associated with ocular demodicidosis (Fisher exact test, p = 0.017). Tea tree oil treatment was given to 31 eyes with recurrent chalazion associated with Demodex infestation. Among the treatment group, all cases except one had no recurrence after the TTO treatment. The success rate of preventing recurrence is 96.8%. Treatment of TTO was found to be associated with preventing recurrence of chalazion associated with Demodex infestation (Fisher exact test, p = 0.002). CONCLUSIONS: The possibility of demodicidosis should be considered in adults presenting with recurrent chalazia. Tea tree oil eyelid scrubs is an effective treatment in preventing recurrence.

[Measurement of the index of infection by Demodex spp in patients with chronic blepharitis and in patients without other ocular diseases]. / Determinación de índice de infestación por Demodex spp, en pacientes con blefaritis crónica y en pacientes sin otra patología ocular.

BACKGROUND: Infestation by Demodex spp. in the palpebral edge follicles in humans is common. However, these mites are not routinely diagnosed in patients with or without ocular pathologies in Chile and their relevance is unclear. One of the eye diseases most related to infestation by Demodex spp. is blepharitis, a chronic inflammation of the eyelid margin with intermittent exacerbations, which is very common in ophthalmic practice. Its management is prolonged treatment, which is often ineffective, leading to relapses and frustration of patient and treating physician. Blepharitis can be typed by its etiology into various types, one of them is caused by Demodex folliculorum and another species, D. brevis. OBJECTIVE: The overall objective was to detect the presence and estimate the rate of infestation of Demodex spp. in healthy subjects and in patients with ocular pathology such as blepharitis, bacterial conjunctivitis, chalazion, and stye. PATIENTS AND METHODS: Samples of tabs from both lower eyelids of ophthalmologically healthy patients (23) and patients with ocular pathologies (9) were mounted in immersion oil as described in literature, then visualized with a 10x objective and confirmed with 40x objective. RESULTS: Detection rates of eggs, nymphs or adults of Demodex spp. in patients with and without ophthalmological problems were above and below 0.5 mites per tab, respectively. D.folliculorum was the species most frequently found. DISCUSSION: The results are consistent with the international literature on both the rate of infestation as the predominant species. CONCLUSION: This paper is the first study in Chile on this subject and represents a significant contribution to ophthalmic clinical diagnosis and treatment of patients with this disease.

Determinación de índice de infestación por Demodex spp, en pacientes con blefaritis crónica y en pacientes sin otra patología ocular / Measurement of the index of infection by Demodex spp in patients with chronic blepharitis and in patients without other ocular diseases

Infestation by Demodex spp. in the palpebral edge follicles in humans is common. However, these mites are not routinely diagnosed in patients with or without ocular pathologies in Chile and their relevance is unclear. One of the eye diseases most related to infestation by Demodex spp. is blepharitis, a chronic inflammation of the eyelid margin with intermittent exacerbations, which is very common in ophthalmic practice. Its management is prolonged treatment, which is often ineffective, leading to relapses and frustration of patient and treating physician. Blepharitis can be typed by its etiology into various types, one of them is caused by Demodex folliculorum and another species, D. brevis. Objective: The overall objective was to detect the presence and estimate the rate of infestation of Demodex spp. in healthy subjects and in patients with ocular pathology such as blepharitis, bacterial conjunctivitis, chalazion, and stye. Patients and Methods: Samples of tabs from both lower eyelids of ophthalmologically healthy patients (23) and patients with ocular pathologies (9) were mounted in immersion oil as described in literature, then visualized with a 10x objective and confirmed with 40x objective. Results. Detection rates of eggs, nymphs or adults of Demodex spp. in patients with and without ophthalmological problems were above and below 0.5 mites per tab, respectively. D.folliculorum was the species most frequently found. Discussion: The results are consistent with the international literature on both the rate of infestation as the predominant species. Conclusion: This paper is the first study in Chile on this subject and represents a significant contribution to ophthalmic clinical diagnosis and treatment of patients with this disease.

La infestación por Demodex spp. en los folículos del borde palpebral en humanos es frecuente; no obstante, en Chile no se diagnostica de rutina la presencia de estos ácaros en pacientes sin o con patologías oculares por lo cual no se conocen aspectos de esta parasitosis. Una de las patologías oculares que más se relaciona con infestación por Demodex spp. es la blefaritis, enfermedad muy común en la práctica oftalmológica, que cursa con inflamación crónica del borde palpebral, con exacerbaciones intermitentes de los síntomas. Su manejo suele llevar mucho tiempo frecuentemente ineficaz, con múltiples recaídas que terminan desmoralizando al paciente y, al médico que las trata. De acuerdo a la etiología, se caracterizan varios tipos de blefaritis y una de ellas es asociada a Demodexfolliculorum, existiendo también la especie D. brevis. Objetivo: Detectar la presencia y calcular el índice de infestación de Demodex spp. en pacientes sanos y en pacientes con alguna patología ocular como blefaritis crónica, conjuntivitis bacteriana, chalazión y orzuelo. Pacientes y Métodos: Se tomaron muestras de pestañas desde el párpado inferior de ambos ojos en pacientes oftalmológicamente sanos23 y pacientes con patologías oculares9 las que fueron montadas en aceite de inmersión según técnica descrita en la literatura, visualizadas con objetivo 10x y confirmadas con objetivo 40x. Resultados: Se encontró la presencia de huevos, ninfas y ejemplares adultos de D. folliculorum y D. brevis, tanto en pacientes normales como en pacientes oftalmológicos siendo el índice de infestación menor a 0,5 ácaros por pestaña en los pacientes sanos y mayor o igual a 0,5 en pacientes oftalmológicos. La especie más frecuentemente encontrada fue D. folliculorum. Discusión: Los resultados encontrados coinciden con la literatura internacional tanto en el índice de infestación como en la especie predominante. Conclusión: Este trabajo constituye el primero realizado en Chile en esta temática, de acuerdo a la literatura revisada, lo cual constituye un gran aporte al diagnóstico clínico oftalmológico con implicancias en el tratamiento de estos pacientes.

[Blepharitis due to Demodex: myth or reality?]. / Blépharite à Démodex: mythe ou réalité?

PURPOSE: Demodex folliculorum has been incriminated in the development of blepharitis although much controversy persists. Certain authors suggest that Demodex is a direct pathogen in chronic palpebral conditions while others consider the saprophyte to be innocuous to skin. METHODS: We conducted a prospective study of eyelashes in 100 persons, searching for Demodex folliculorum and chronic blepharitis. Microscopy in immersion oil after storage in a moist chamber was performed. RESULTS: The incidence of Demodex folliculorum was very high in patients with blepharitis compared with normal controls. Incidence increased with age. Harmless cuffs around the base of the eyelashes was found in 4% with Demodex irradior. CONCLUSION: Demodex should be considered as the cause of chronic blepharitis. Anti-Demodex treatment is indicated when the parasite is found.