Ácaros del género Demodex: ¿parásitos colonizadores de personas sanas o asociados a patología ocular? / Demodex genus: colonizing parasites of healthy people or mites associated with ocular pathology?

Las especies Demodex folliculorum y Demodexbrevis, responsables de la demodicosis humana, afectan la piel y en ocasiones están vinculadas con afecciones oculares. El objetivo de este trabajo fue conocer si existe asociación significativa entre la presencia del ácaro y de patologías palpebrales, y el papel de factores como la edad y el sexo de los pacientes. Se analizaron las pestanas de un conjunto de pacientes sintomáticos y asintomáticos (n = 72) de entre 9 y 82 años. El 53% de los pacientes fueron positivos para la presencia del ácaro Demodex. De ellos, el 66% manifestó síntomas o patologías oculares, dentro de las cuales la blefaritis y el ojo seco resultaron prevalentes. Se observaron asociaciones significativas tanto entre la presencia de este ácaro y una edad mayor de 60 años (p < 0,001), como entre la presencia del ácaro y ojo seco o blefaritis o ambos (p <0,001). Consideramos necesaria la búsqueda de Demodex sp. en pacientes con síndrome de ojo seco o blefaritis, especialmente durante la inmunosenescencia, a fin de instaurar tratamientos antiparasitarios específicos.

Demodex folliculorum and Demodex brevis are mites that are responsible for human demodicosis affecting skin and frequently linked to ocular diseasess. The aim of this work was to determine the association between Demodex sp. and eyelid and eyelash diseases and to establish the predisposing factors for acquiring this parasitic disease. Eyelashes from symptomatic and asymptomatic patients (n = 72) between 9 and 82 years old were analyzed, where 53% were positive for Demodex sp., of which 66% manifested ocular symptoms and pathologies, blepharitis and dry eye being prevalent. Significant correlations between Demodex and patients over 60 years of age (p <0.001) and between Demodex sp. and dry eye patients / blepharitis (p <0.001) were observed. We consider that it is necessary to search for Demodex sp. especially in those patients suffering from dry eye and blepharitis and/or during immunosenescence in order to implement specific antiparasitic treatments.

Unilateral phthiriasis palpebrarum infestation in a child during occlusion therapy for amblyopia: case report

An 8-year-old mentally retarded boy is brought to the hospital because of itching and burning at his right eye for 10 days. He was on full time right eye occlusion therapy for left amblyopia. Slit lamp examination revealed nits and adult lice anchored to the eyelashes in his occluded eye. Eyelashes and all detected lice and nits were mechanically trimmed, and sent for parasitological examination, which confirmed the diagnosis. Upon familial evaluation for additional infestation, the father was also found to have genital phthiriasis pubis and received appropriate treatment. While phthiriasis palpebrarum in children may signify sexual abuse, a detailed investigation by a child psychiatrist was performed and revealed no sign of abuse. Since the infestation was at only on occluded eye, the most possible explanation for the transmission was evaluated as the misusage of the adhesive patch in our case. In conclusion, sexual abuse should be excluded in children with phthiriasis palpebrarum and parents of amblyopic children on occlusion therapy should be warned about the importance of the hygiene of the patching in order to avoid any kind of infection and infestation

Demodex folliculorum on the eyelash follicule of diabetic patients / Demodex folliculorum nos cílios de pacientes diabéticos

PURPOSE: To compare the prevalence of Demodex folliculorum on the eyelashes of patients with proliferative diabetic retinopathy and healthy voluntaries. METHODS: Type 2 diabetic patients with proliferative retinopathy and age- and gender-matched healthy voluntaries (group control) underwent a slit lamp examination which three eyelashes containing cylindrical dandruff were removed from each lid by fine forceps. The lashes were dyed with fluorescein and the presence of Demodex folliculorum was verified by direct visualization under a light microscope. The mites were recognized based on its morphology and peculiar movement. The results were expressed in "positive" when at least one mite on one lash was found and "negative" when no mite was identified. The Chi-square test was used for comparing mites' presence in both groups. RESULTS: Forty-two patients were included in each group. The age ranged from 50 to 60 years old, with a mean of 56.4 ± 5.2 years. The male:female ratio was 0.6:1. There was no statistically significant difference with regard to age and gender in both groups (p>0.05). Demodex folliculorum was significantly more prevalent in diabetic patients (54.8 percent) than in control patients (38.1 percent) (p=0.048). CONCLUSION: Demodex folliculorum was more prevalent in diabetic patients than in healthy voluntaries, independently of gender and age.

OBJETIVO: Comparar a prevalência de Demodex folliculorum nos cílios de pacientes com retinopatia diabética proliferativa e voluntários normais. MÉTODOS: Pacientes com diabetes mellitus tipo 2 apresentando retinopatia proliferativa e voluntários normais com mesma distribuição de sexo e idade (grupo controle) foram submetidos a exame em lâmpada de fenda. Três cílios com secreção "em colarete" foram removidos de cada pálpebra com pinça delicada. Os cílios foram corados com fluoresceína e a presença de Demodex folliculorum foi verificada por visualização direta através de microscópio de luz. As larvas foram reconhecidas baseadas em sua morfologia e movimentos peculiares. Os resultados foram expressos em "positivo" quando foi encontrada pelo menos uma larva em um cílio e "negativo" quando nenhuma larva foi encontrada. O teste de Chi quadrado foi utilizado para comparar a presença das larvas nos dois grupos. RESULTADOS: Quarenta e dois pacientes foram incluídos em cada grupo. A idade variou de 50 a 60 anos com média de 56,4 ± 5,2 anos. A relação masculino:feminino foi de 0,6:1. Não houve diferença estatisticamente significante com relação ao sexo e idade entre os dois grupos (p>0,05). Demodex folliculorum foi significantemente mais prevalente em pacientes com diabetes (54,8 por cento) que no grupo controle (38,1 por cento) (p=0,048). CONCLUSÃO: Demodex foliculorum foi mais prevalente em pacientes diabéticos que em voluntários normais, independentemente do sexo e da idade.

Prevalencia de infección por Demodex folliculorum en pacientes que acuden a consulta general de oftalmología / The prevalence of Demodex folliculorum infection in patients attending a general ophthalmological consultation

Objetivos Determinar la prevalencia de infección por Demodex folliculorum en pacientes que asisten a consulta general de oftalmología, y su asociación con blefaritis. Métodos Estudio descriptivo de prevalencia. En forma aleatoria se seleccionaron 128 sujetos que asistieron al Centro Oftalmológico Virgilio Galvis y se determinó la presencia de Demodex folliculorum en 4 pestañas de cada uno. Resultados La prevalencia de infección por Demodex folliculorum fue 42,1 % (n= 54). Se diagnosticó blefaritis en el 38,3 % de los pacientes (n=49) y el 63,2 % de ellos (n=31) fueron positivos para D. folliculorum. En el grupo sin blefaritis (n=79) solo el 29,2 % de los individuos tenían el ácaro (n=23) (p=0.0003). Además se encontró una mayor cantidad de parásitos en los pacientes con blefaritis (índice de carga parasitaria 12,7 vs 5,1 (p=0.0001). El 25 % (n=32) de los participantes presentaban descamación en forma de cilindros y en estos el 96,9 % tenían el ácaro (n= 31), mientras que en los sujetos que no tenían cilindros (n=96) el ácaro estuvo presente solo en el 24 % (n=23). Conclusiones El Demodex folliculorum es un parásito que se encuentra en personas sin lesiones oculares, pero que es más frecuente y presenta una mayor carga parasitaria en pacientes con blefaritis. Nuestros resultados sugieren la necesidad de investigar la presencia de Demodex folliculorum en todo paciente con blefaritis y especialmente en los casos en que se observe presencia de descamación en forma de cilindros en las pestañas.

Objectives Determining Demodex folliculorum infection prevalence in patients attending general ophthalmological consultation and such infection's association with blepharitis. Methods This was a descriptive study of such prevalence. 128 subjects who attended the Virgilio Galvis Eye Centre were randomly selected and the presence of D. folliculorum was determined in 4 eyelashes taken from each of them. Results D. folliculorum infection prevalence was 42.1 % (n=54); blepharitis was diagnosed in 38.3 % of the patients (n=49) and 63.2 % of them (n=31) were positive for D. folliculorum. Only 29.2 % of the individuals in the group without blepharitis (n=79) had mites (n=23) (p=0.0003). A higher number of parasites was found in patients with blepharitis (12.7 parasitic load index cf 5.1; p=0.0001); 25 % (n=32) of the participants had scaling in the form of cylinders and 96.9 % of these had the mites (n=31), whereas the mite was only present in 24 % (n=23) of subjects who had no cylinder-type scaling (n=96). Conclusions Demodex folliculorum is a parasite found in people without ocular lesions; however, it is more frequent and has a higher parasite burden in patients with blepharitis. Our results suggested the need for investigating the presence of D. folliculorum in all patients suffering from blepharitis, especially in cases where cylinder-type scaling has been observed in their eyelashes.

[Demodex blepharitis about two cases]

Demodex is a mite commonly found in eyelash hair follicles and sebaceous glands of healthy people. This mite has been reported in many chronic cases of blepharitis. Two cases of very long term observation and clinical findings of chronic blepharitis caused by demodex folliculorum are presented. A 60 year old woman suffered from recurrent blepharoconjunctivitis during ten years treated locally with antibiotics and steroids. We carried out microbiological test results from the epilated eyelashes. The second case was a 25 year old man who was treated for over five years for blepharitis and repetitive chalazions treated by topically steroids and antibiotics. A significant thickening of the blood vessels in the eyelid and numerous cylindrical cuffs of dry discharge around the base of the eyelashes persuaded us to carry out microbiological tests result from the epilated eyelashes. Demodex folliculorum considered as saprophytic mite may play a pathogenic role in ocular diseases

Crab louse infestation of eyelashes

To present clinical features and management of ten patients of crab louse infestation of eyelashes Present study includes ten cases of crab louse infestation of eyelashes seen during last few years in eye OPD of Services Hospital and Jinnah Hospital Lahore. Patients visiting eye out-patients department who were reported to have crab louse infestation of eyelashes were examined in detail including systemic examination. Infested parts of the body were photographed as well. The adult patients were asked about similar problem in their sexual partners and the parents of children were inquired similarly. All patients were treated with adequate washing of eyelashes and other involved parts with soap and water and application of any ophthalmic preparation having petroleum base e.g. Polyfax eye ointment in the conjunctival sac and eyelashes and anti-lice dermal preparation e.g. Lotrix [Permethrin] skin preparation to other parts. All patients were followed for a period of three months performing examination of eyelashes with slitlamp and systemic examination every two weeks. Seven out of ten patien ts were adults [70%], five males and two females, and remaining three patients were children [30%]. Forty percent of patients [4/10 patients] had related systemic lesions, including blue gray macules [Maculae caeruleae] and the bullous lesions. In addition to systemic dermatological manifestations, ocular symptoms included deposits in the roots of eyelashes, irritation or feeling of some thing moving in lid margins, mild lacrimation and redness. Ocular examination revealed multiple lice anchoring themselves in the roots of eyelashes sucking blood, along with hundreds of nits cemented with eyelashes. There was a mild conjunctival congestion. Removal of lice resulted in formation of small ulcers of margin of lid. Adequate washing with soap and water, followed by application of Polyfax eye ointment for two to three weeks, resulted in complete cure of the palpebral disease. This study emphasizes the significance of an infrequently seen clinical condition of crab louse infestation of eyelashes, not only as a venereal disease expecting much higher number of infections but also as an important cause of refractory cases of chronic irritation of eyes with blepharitis. Careful examination of eyelids with slitlamp microscope may establish the diagnosis. All the sexual partners should be treated simultaneously. Other parts of the body having less dense population of hair should be examined and adequate measures should be taken for the management, including application of anti-lice dermal ointment e.g. Lotrix [Permethrin] skin ointment

Prevalencia de Demodex folliculorum en pacientes con blefaritis crónica / Prevalence of Demodex Folliculorum in patients with cronic blepharitis

La etiología de las blefaritis crónicas es diversa. Demodex folliculorum es un ácaro que habita en las glándulas de Meibomio y en los folículos de las pestañas. Objetivo. Conocer la prevalencia y características clínicas de la infestación por Demodex folliculorum en pacientes con blefaritis crónica. Materiales y métodos. Realizamos un estudio prospectivo, transversal, comparativo y observacional. Se incluyeron pacientes con blefaritis crónica realizando cultivo, antibiograma y búsqueda de Demodex folliculorum en folículos de pestañas, comparándose este último parámetro con un grupo de sujetos sanos. Resultados. Evaluamos 100 pacientes por grupo. Encontramos positividad para Demodex folliculorum en 35 por ciento de los casos con blefaritis y en 7 por ciento de los controles sanos. La prevalencia más alta se encontró después de los 60 años (51 por ciento), el sexo femenino fue el mas afectado (85 por ciento). Los collaretes en la base de las pestañas, alteraciones en su dirección, madarosis y obstrucción de glándulas de Meibomio sugieren la presencia del parásito. Conclusiones. Demodex folliculorum muestra mayor prevalencia en pacientes con blefaritis crónica comparada con sujetos sanos siendo más abundante después de los 60 años y predomina en mujeres. Debe considerarse su búsqueda y tratamiento en blefaritis crónicas resistentes al tratamiento.

Blefaritis por Demodex folliculorum / Blepharitis due to Demodex folliculorum

La asociación de blefaritis con la presencia de Demodex folliculorum es probablemente más común de lo que el oftalmólogo supone. Este ácaro parasita los folículos pilosos, las glándulas sebáceas y las pestañas del hombre. Tiene una amplia distribución en todo el mundo. El papel patogénico de Demodex folliculorum es aún materia de controversia. Se han encontrado dos tipos: el Demodex folliculorum longus y el Demodex folliculorum brevis. Presentamos su morfología, ciclo evolutivo, hábitat, patogénesis y tratamiento de este diminuto parásito.

Infestación de los párpados de un niño por phthirus pubis / Eyelids infestation by phthirus pubis in a boy

A clinical case of phthirus pubis infestation of the eyelids in an eight year old boy is presented. He complained of a bilateral eyelids inflammation for the last two weeks which had not healed with a daily application of a collyrium. Physical examination showed the presence of small dark spheres, of approximately 1 mm. attached to the proximal extreme of the eyelashes. A microscopical examination of these elements permitted to identify adults and eggs of P. pubis. Neither insects nor eggs were found in the scalp of the patient. Treatment consisted in the extraction of the parasite elements by means of a fine forceps after the application of liquid vaseline in the eyelashes. A total of 23 adults insects and 32 eggs was removed. The boy proceeded from a boarding school, where none of the other 27 children was found infested and stayed there form monday to friday, going home for week ends. It was impossible to contact the mother, the most probable source the patient infestation, for epidemiological and prophylactical purposes