[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.