Prevalence of Demodex spp. in patients with chronic blepharitis.

Blepharitis is a very common disease in ophthalmology, dermatology and allergy practice. It generally follows a chronic course and is frequently associated with objective and/or subjective symptoms such as epiphora, red eye, dandruff, gritty sensation, itching, burning, photophobia, and blurred vision. The purpose of this study is to analyze the prevalence of Demodex spp. in patients with symptoms of chronic blepharitis. An analytical cross-sectional study was conducted in the period between 2016 and 2020. All patients with symptoms of chronic blepharitis who underwent a parasitological test of eyelashes (Rapitest) in the Dermatology Department of the Hospital Italiano de Buenos Aires were included. Those with previously established blepharitis due to another infectious cause were excluded. We analyzed 972 patients. Sixty percent (n=585) underwent a positive Rapitest for the presence of Demodex spp. Seventy five percent (n=728) were women. There were no significant differences in the prevalence associated with sex (p=0.38). Among the patients positive for Demodex spp., 65% (n=628) were older than 60 years old. The most frequently associated symptom was itching, present in 35% (n=342). A statistically significant decrease in the number of consultations was observed during the cold months of the year (May-June-July-August). Our results show a high prevalence of Demodex spp. in patients with chronic blepharitis. As its presence reveals a direct association with age, we recommend looking for this parasite in this age group.

Demodicosis in Different Age Groups and Alternative Treatment Options-A Review.

Infestation with Demodex mites is a common occurrence, especially in adults and the elderly. More recent attention has been paid to the presence of Demodex spp. mites in children, even ones without comorbidities. It causes both dermatological and ophthalmological problems. The presence of Demodex spp. is often asymptomatic, thus it is suggested to include parasitological investigation tests in dermatological diagnostics, in addition to bacteriological analysis. Literature reports show that Demodex spp. are related to the pathogenesis of numerous dermatoses, including rosacea or demodicosis gravis, and common eye pathologies reported by patients such as dry eye syndrome or ocular surface inflammatory conditions, such as blepharitis, chalazia, Meibomian gland dysfunction, and keratitis. Treatment of patients is a challenge and is usually prolonged, therefore it is important to carefully diagnose and properly select the therapy regimen for the treatment to be successful, and with minimal side effects, especially for young patients. Apart from the use of essential oils, research is ongoing for new alternative preparations active against Demodex sp. Our review was focused on the analysis of the current literature data on the available agents in the treatment of demodicosis in adults and children.

A retrospective study of cases of canine demodicosis submitted to a commercial diagnostic laboratory servicing the United Kingdom and Ireland (2017-2018) part 2; Aerobic culture and antimicrobial susceptibility results.

Clinical diagnostic reports from 508 cases of canine demodicosis diagnosed either by histological or skin scraping analysis from a United Kingdom Accreditation Service (UKAS) accredited veterinary diagnostic laboratory servicing the United Kingdom (UK) and Ireland were evaluated. Of the 508 cases, 284 had skin swabs submitted for culture on the same day the skin biopsy and/or skin scraping were obtained. Dogs with juvenile-onset (JO) demodicosis represented 57.4% of these cases, whilst adult-onset (AO) cases comprised 42.6%. The data revealed that overgrowth of pathogenic bacteria was more common in AO demodicosis cases (75.2%) in comparison to the JO cases (57%). Adult-onset cases also had increased involvement of bacteria belonging to multiple genera and/or yeast (28.9%) in comparison to JO cases (18.4%). Pruritus was significantly associated with an overgrowth of Staphylococcus pseudintermedius (p < 0.001). Resistance to one or more antimicrobial classes was noted in S. pseudintermedius isolates from 56.3% of JO cases with 10.3% of these cases being classified as Multi-Drug Resistant (MDR). Similarly, 51.9% of S. pseudintermedius isolates from the AO cases were noted to be resistant to one or more antimicrobial class with 8.6% of these cases being considered MDR. Cephalosporins were the most frequently administered antimicrobial class noted in submission histories, followed by the penicillin and fluoroquinolone classes. Whilst our findings reveal a high prevalence of concurrent overgrowth of pathogenic bacteria warranting therapeutic intervention in canine demodicosis, the presence of resistance within isolates highlights the need for prudent selection and targeted use of antimicrobial therapy that encompass the key principles of antimicrobial stewardship.

Investigation of the Prevalence of Demodex spp. in Dermatological Diseases

Objective: An increase in the counts of the Demodex mites that exist in the microbiota of healthy individuals may lead to some dermatological diseases. This study aimed to investigate the prevalence of Demodex spp. among patients diagnosed with acne vulgaris, rosacea, perioral dermatitis, seborrheic dermatitis, eczema, and pityriasis folliculorum and the relationship between the demographic and clinical data of such patients and Demodex. Methods: This study included 144 patients (70 with acne vulgaris, 6 with pityriasis folliculorum, 15 with seborrheic dermatitis, 39 with rosacea, 8 with eczema, and 6 with perioral dermatitis) and 73 healthy subjects. We evaluated Demodex positivity using the standard superficial skin biopsy method in all groups. The presence of more than five Demodex mites per square centimeter was considered positive at the diagnosis. Results: Of the 144 patients included in the study, 107 (74.3%) were female, and 37 (25.7%) were male, while 40 (54.8%) of the 73 healthy subjects were female, and 33 (45.2%) were male. Twenty-one patients (14.5%) and five of the healthy subjects (6.8%) tested positive for Demodex. We found that Demodex positivity rates in the rosacea and acne vulgaris groups were higher than in the control group. However, this level was not statistically significant (p>0.05). We found the highest positivity rate among the patient groups in the pityriasis folliculorum (4/6, 66.7%), rosacea (8/39, 20.5%), and perioral dermatitis (1/6, 16.7%) groups. Lastly, we found no statistically significant relationship between the demographic and clinical characteristics of the groups and Demodex positivity (p>0.05). Conclusion: The present study is the only study that investigated Demodex positivity in six different dermatological diseases. Based on the results, we believe that investigating Demodex spp. positivity in dermatological diseases such as acne vulgaris, rosacea, and pityriasis folliculorum would be beneficial for early diagnosis and treatment.

Demodex spp / Dermodex spp

Los ácaros ectoparásitos del género Demodex spp (>140 especies) pertenecen a la familia Demodicidae, superfamilia Cheyletoidea, suborden Prostigmata, orden Trombidiformes, superorden Acariformes. Fueron descritos por primera vez en 1841 por Henle y Berger. El término Demodex deriva del griego: demos = grasa y dex = gusano incrustado. Tienen una longitud de 0.2- 0.4 mm, son transparentes y elongados. Su cuerpo se divide en tres secciones principales: 1) gnatosoma, región anterior, en donde se encuentra la apertura bucal; 2) podosoma, región en la que se encuentran sus cuatro pares de patas; y 3) el opistoma, región caudal o cola. Se adquieren poco después del nacimiento y se consideran parte del microbiota normal de muchos mamíferos, así como también del ser humano, en particular de la unidad pilosebácea. Por lo tanto, se ubican principalmente en el rostro, cuero cabelludo y región superior del tronco. Todas estas áreas corporales se caracterizan por la alta secreción sebácea, alimento primordial para el crecimiento y desarrollo de este ácaro; razón por la cual, además, su densidad aumenta durante la pubertad, periodo cuando proliferan las glándulas sebáceas. Dentro de las especies del género, encontramos exclusivamente en humanos, a D. folliculorum (440 µm), habitando frecuentemente el infundíbulo folicular y D. brevis (240 µm), que se localiza predominantemente en los ductos sebáceos y glándulas tarsales a nivel ocular.(AU)

The Retrospective Analysis of Demodex spp. Results in Aydin Adnan Menderes University Faculty of Medicine Hospital Parasitology Laboratory.

OBJECTIVE: Demodex spp. is one of the most common ectoparasites in humans. The aim of the present study is to evaluate the positivity of Demodex spp. in our Parasitology Laboratory, retrospectively. METHODS: The study included Demodex spp. suspected cases from different departments between 2008 and 2017. The link between Demodex spp. and demographics and symptoms was investigated. In addition, Demodex spp. was evaluated regarding symptoms and distribution pattern (U, T and diffuse region). RESULTS: Demodex spp. was detected in 576 (78%) of 738 cases. There was no relationship between sex and parasite positivity, but frequency was lower in cases below 19 years. There was a relationship between presence of parasite and redness, itching, burning and rash. The parasite density was higher in U region (n=335, 58.2%). When clinical findings and parasite number were statistically compared; itching, burning and rash were significantly higher in patients with parasite density ≥5 parasites/cm2, while a similar result was not observed in patients with redness. CONCLUSION: Given its prevalence and its relationship with the clinical findings; we believe that Demodex is an important parasitic disease for our province and should be evaluated in cases with various dermatological complaints in the face.

Prevalence of Demodex spp. in eyelashes of a university's population in Santiago, Chile. / Prevalencia de Demodex spp. en pestañas de una población universitaria en Santiago, Chile.

OBJECTIVE: To determine the presence of Demodex spp. in the eyelashes' pilosebaceous unit in volunteers of one campus of a private university. MATERIALS AND METHODS: The volunteers underwent anamnesis, biomicroscopic study and samples were taken of 8 eyelashes, 2 of each eyelid of both eyes. The eyelashes were mounted on a slide and observed under a light microscope to determine the presence and quantity of mites. RESULTS: 200 volunteers were recruited, determining the prevalence of Demodex spp. in 54 (27%) of them. Of the positive cases, 40 (74.1%) presented signs and/or symptoms of blepharitis, 43 (79.7%) presented the mite in one eye and an average infestation rate of 0.65 Demodex spp. per eyelash was obtained. CONCLUSIONS: Approximately one in four of the volunteers studied without a diagnosis of blepharitis was a carrier of the parasite, of which a significant percentage presented some type of sign and/or symptom of this pathology which was related to a higher rate of infestation (p<0.05).

Demodex Infestation in Patients with Rosacea

Objective: Although the etiology of rosacea is not known exactly, it is thought as a multifactorial disease. Demodex spp. are asymptomatic saprophytic ectoparasites living in hair follicles and sebaceous glands. The aim of this study was to investigate the frequency of Demodex spp. in patients with rosacea and compare with the control group by using superficial skin biopsy method. Methods: Seventy seven patients with rosacea and 31 control patients were included in the study. In patients, for the determination of density of Demodex spp., non-invasive standard superficial skin biopsy method was applied. Detection of ≥5/cm2 Demodex spp. was considered positive. Results: The mean age of the patients was 44.5±14.6 years and the mean age of the control group was 48.2±14.9 years. Of the patients, 55.1% had erythema-telangiectatic type, 43.5% had papulopustular type, and 3.9% had fimatous type lesions. Demodex infestation was positive in 33.8% of the patients with rosacea and this rate was 9.7% in the control group. Difference was statistically significant. There was no significant difference in Demodex spp. positivity in terms of gender in patients with rosacea. Conclusion: The importance of Demodex infestation in patients with rosacea has been increasing in recent years. Considering some studies conducted in our country, we think that the investigation of Demodex spp. in patients who are considered to have rosacea will be beneficial in the terms of early diagnosis and treatment.

The Investigation of Prevalence of Demodex spp. in University Students: The Case of the Faculty of Health Sciences

Objective: The aim of this study was to determine the prevalence of Demodex spp. in college students, mostly adolescent individuals. Methods: A questionnaire including questions about the risk factors of Demodex spp. was administered to college students. Samples were taken with Standard Superficial Skin Biopsy method and examined under light microscope. Results: Presence of Demodex spp. was detected in 160 (42.7%) students out of 375 totally; 126 out of 291 nursing students (43.3%) and 34 out of 84 midwifery students (40.5%). It was detected in 47.3% of males and 40.2% of females. There was a statistically significant difference in terms of the prevalence of Demodex spp. between those who used foundation cream/make-up products and those who did not, and between those who removed hair and those who did not (p<0.05). There was no relationship between other variables and Demodex spp. prevalence. Conclusion: It is concluded that Demodex spp. is very common among college students in Kars. Dermatologists should also consider the existence of Demodex spp. in the etiology and pathogenesis of dermatoses which develops in the facial region of individuals in this group of age.

Efficacy of lotilaner (Credelio™), a novel oral isoxazoline against naturally occurring mange mite infestations in dogs caused by Demodex spp.

BACKGROUND: The oral systemic efficacy of lotilaner (Credelio™, Elanco) was evaluated against Demodex spp. in naturally infested dogs with generalized demodicosis. METHODS: In this study, 10 dogs with clinical signs of generalized demodicosis and positive for Demodex spp. mites based on skin scrapings were assigned to a single group orally treated with lotilaner (minimum dose of 20 mg/kg) on Days 0, 28 and 56. RESULTS: For lotilaner-treated dogs, pre-treatment mite counts based on skin scrapings performed at five different sites were reduced by > 99.9% (P < 0.0001) up to 56 days after the first and second monthly doses. No live mites were detected after Day 56 out to and including Day 84 post-treatment for 100% efficacy of each dog's Demodex mite infestation. Nine of 10 dogs were 100% mite-free from Day 28 (first evaluation) through Day 84 (end of study) and live mites were only found once on one dog (Day 56) following treatment with lotilaner. All dogs in the lotilaner-treated group showed marked improvement in the clinical signs of demodicosis and there were no drug associated adverse events. A marked improvement in hair re-growth was observed in all the dogs from 6 weeks following initiation of treatment. CONCLUSIONS: In this study lotilaner administered at a minimum oral dose of 20 mg/kg was highly effective in reducing and eliminating live mite counts in dogs with natural infestations of Demodex spp.

The effects of sebum configuration on Demodex spp. density.

BACKGROUND/AIM: Demodex spp. are ectoparasites living in the pilosebaceous units, which feed on the host's sebum and cellular proteins. The protective barrier of the skin consists of sebum secretion, moisture, and the acid mantle. In this study, we aimed to determine the effects of skin sebum, moisture, pH levels, and sebum configuration on Demodex spp. density. MATERIALS AND METHODS: Forty-five patients who had demodicosis were enrolled in the study group, while the control group consisted of 40 subjects without demodicosis. Body fat percentage, serum triglyceride and cholesterol levels, skin sebum, moisture, and pH levels were measured. Demodex spp. density was determined with a standardized skin surface biopsy. Sebum samples were taken from the forehead and a high-performance thin-layer chromatography (HPTLC) method was performed on these samples. Subsequently, densitometric analyses were applied to the HPTLC plates. RESULTS: Demodex spp. were found on the cheeks and lived in an alkali environment. Skin sebum and moisture levels were low in all groups. The skin pH levels and cholesterol ester in the sebum configuration were determined to be significantly higher in the group with demodicosis. CONCLUSION: We suggest that Demodex spp. may use cholesterol ester in the sebum as nutriment. In other words, cholesterol ester may be a suitable growth medium for the proliferation of Demodex spp.

Efficacy of sarolaner, a novel oral isoxazoline, against two common mite infestations in dogs: Demodex spp. and Otodectes cynotis.

The efficacy of sarolaner (Simparica™, Zoetis) was evaluated against Demodex spp. in dogs with generalized demodicosis and against Otodectes cynotis (otodectic mange) in dogs with induced infestations. In the first study, 16 dogs with clinical signs of generalized demodicosis and positive for Demodex spp. mites were randomly assigned to treatment with either sarolaner (2mg/kg) orally on Days 0, 30 and 60, or topical imidacloprid (10mg/kg) plus moxidectin (2.5mg/kg) solution every 7 days from Day 0 to Day 81. For sarolaner-treated dogs, pretreatment mite counts were reduced by 97.1% at 14days and 99.8% by 29 days after the first dose, with no live mites detected thereafter. Weekly imidacloprid plus moxidectin resulted in 84.4 and 95.6% reduction at these two time points, respectively, with no mites detected from Day 74 on. All dogs in both groups showed marked improvement in the clinical signs of demodicosis. In the second study, 32 dogs with induced infestations of O. cynotis were randomly assigned (eight per group) to oral sarolaner (2mg/kg) as a single treatment on Day 0 or as a two dose regime (Days 0 and 30), or a placebo group for each of the dose regimes. Sarolaner administered at 2mg/kg as a single oral dose resulted in a 98.2% reduction at Day 30 and two doses of sarolaner, administered one month apart, resulted in a 99.5% reduction in ear mites at Day 60 compared to placebo controls. There were no treatment related adverse events in either study. In these studies, sarolaner at an oral dose of 2mg/kg was highly effective in reducing the live mite counts associated with a natural infestation of Demodex spp. and an induced infestation of O. cynotis. In addition, the Demodex-infested dogs showed a marked improvement in the clinical signs of generalized demodicosis.

Demodex treatment in external ocular disease: the outcomes of a Tasmanian case series.

Demodex species (spp.) have previously been implicated in the pathogenesis of blepharitis. This study aims to correlate improvement in symptoms of external ocular disease with treatment of underlying Demodex spp. This is a prospective, observational case series of patients with chronic external ocular disease. Demodicosis was confirmed by microscopic examination of epilated eyelashes. The main outcome measure was response to the treatment (5 % tee tree oil) in regard to change in subjective symptoms utilising a symptom-based patient questionnaire assessment. Overall patients had a good response to the treatment in terms of improvement or resolution of symptoms, with 91 % of patients reporting at least some improvement in symptoms. The treatment of underlying Demodex spp. appears to result in improvement of symptoms in patients with long standing external ocular disease and underlying Demodex spp. infestation.

Demodex spp en pacientes con blefaritis crónica / Demodex spp in chronic blepharitis patients

Background: Blepharitis is a very common disease in the ophthalmologic practice generally taking a chronic course with intermittent exacerbations. Several studies have linked the presence of Demodex folliculorum with chronic blepharitis, since the mite has the capacity to perpetuate the follicular inflammatory process. The prevalence of infection by Demodex spp. is variable depending on the population. In Paraguay, information on the frequency of the infestation in patients with chronic blepharitis is not available. Aim : To determine the frequency of Demodex spp, and the ocular microbiota in patients with chronic blepharitis attending the Department of Ophthalmology at the Teaching Hospital of the National University of Asuncion. Patients and Methods: Consecutively, 28 patients with chronic blepharitis, who agreed to participate in the study, were included. Eyes lashes from the upper and lower eyelids were extracted for immediate mite search by direct observation under a light microscope. Samples from eyelids were taken with Kimura spatula and then cultured on blood agar and in enrichment media and incubated in 5% CO2 at 35° C for 72 hours. Results: Among participants, females were more frequent (64%), the age ranged from 17 to 87 years (mean: 38.0; SD: ±13.5 years). The prevalence of Demodex sp was 54%. Bacteria were isolated 92.9% of cases, most frequently coagulase-negative staphylococci (75%). No association was found between socio-demographic or clinical characteristics and the presence of Demodex sp. Conclusion: The observed high prevalence of infestation by Demodex spp in patients with chronic blepharitis is consistent with other studies.

Introducción: La blefaritis es una enfermedad muy común en la práctica oftalmológica, generalmente de curso crónico con exacerbaciones intermitentes. Varios estudios han relacionado la presencia del Demodex folliculorum con la blefaritis crónica, por su capacidad potencial de perpetuar el proceso inflamatorio a nivel folicular. La frecuencia de D. folliculorum varía de acuerdo a la población. Objetivo: Determinar la presencia de Demodex spp y, caracterizar la microbiota ocular en pacientes con blefaritis crónica y dar a conocer estos resultados. Pacientes y Métodos: Las muestras fueron obtenidas de pacientes que consultaron en la Cátedra de Oftalmología del Hospital de Clínicas de la Universidad Nacional de Asunción (UNA). Fueron incluidos en forma consecutiva 28 pacientes con blefaritis crónica que accedieron a participar en forma voluntaria en el estudio. Se extrajeron las pestañas del párpado superior e inferior de los pacientes para la búsqueda inmediata del ácaro por observación directa bajo el microscopio óptico. Para el cultivo de microorganismos se tomaron muestras del párpado con espátula de Kimura, las que fueron cultivadas en agar sangre y en medios de enriquecimiento e incubadas en CO2 al 5% a 35°C durante 72 h. Resultados: El sexo femenino fue más frecuente (64%), el rango de edad estuvo entre 17 y 87 años con una media de 37,9 ± 13,5. Se observó la presencia de Demodex sp en 54% y aislamiento de bacterias en 92,9%; Staphylococcus coagulasa negativa fue el más frecuente (75%). No se encontraron asociaciones entre las características socio-demográficas o clínicas y la presencia de Demodex sp. Conclusión: La alta infestación por Demodex spp observada en los pacientes con blefaritis crónica coincide con otros estudios.

Demodectic mange, dermatophilosis, and other parasitic and bacterial dermatologic diseases in free-ranging white-tailed deer (Odocoileus virginianus) in the United States from 1975 to 2012.

The white-tailed deer (Odocoileus virginianus) is a common and widespread North American game species. To evaluate the incidence, clinical manifestations, demography, and pathology of bacterial and parasitic dermatologic diseases in white-tailed deer in the southeastern United States, we retrospectively evaluated white-tailed deer cases submitted to the Southeastern Cooperative Wildlife Disease Study from 1975 to 2012. Among 2569 deer examined, bacterial or parasitic dermatologic disease was diagnosed in 88 (3.4%) individuals, with Demodex spp (n = 37; 42.0%) and Dermatophilus congolensis (n = 19; 21.6%) as the most common causes. Demodicosis was significantly more common in deer older than 2 years and was most often detected in the fall; no statistically significant sex predilection was identified. Affected animals had patchy to generalized alopecia, often distributed over the head, neck, limbs, and trunk; microscopic lesions included epidermal crusts and cutaneous nodules with mild perifollicular, lymphoplasmacytic inflammation. Dermatophilosis was most common in males younger than 1 year that were often found dead. Crusting, erythema, and alopecia occurred on the face, ears, and distal extremities. Less commonly, infectious dermatologic diseases were associated with other bacteria (n = 13; 14.8%), fungi (n = 5; 5.7%), ectoparasites (chiggers, lice, mites, and ticks; n = 11; 12.5%), and larval nematodes (n = 7; 8.0%). Population-level effects of these diseases in white-tailed deer are likely minimal; however, due to their dramatic presentation, demodicosis, dermatophilosis, and other infectious skin diseases can be of concern to hunters and, in some cases, may have zoonotic potential.

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.