Skin scrapings versus standardized skin surface biopsy to detect Demodex mites in patients with facial erythema of uncertain cause – a comparative study.

Background: Standardized skin surface biopsy (SSSB) is considered to be the gold standard technique to evaluate the density of Demodex mites for the diagnosis of demodicidosis. Potassium hydroxide (KOH) preparation of skin scrapings is a much simpler procedure that can be used to detect pathogens in the superfi cial skin. Objective: To evaluate the reliability of potassium hydroxide preparation of skin scrapings as compared to the standard skin biopsy technique with regard to capacity to detect Demodex mites, time consumed and technician satisfaction. Methods: One hundred outpatients presenting with facial erythema of uncertain cause were enrolled. Standardized skin surface biopsy and potassium hydroxide preparation of skin scrapings were undertaken in adjacent areas on the patients’ right cheek. Limitation: Patients with normal facial skin were excluded from the study. Results: The accuracy of Demodex mite detection by potassium hydroxide preparation of skin-scrapings when compared to the standard procedure is 82%. The sensitivity, specifi city, positive and negative predictive values of this method are 75%, 84.2%, 60% and 91.43%, respectively. There was no statistically signifi cant difference between the standard and skin scraping techniques (P = 0.238) with regard to mite detection. Mean preparation time while using the skin scraping technique was 6 times less than that of the standard technique. For interpretation also, skin scraping technique (3.6 min) consumed much less time than the biopsy technique (9.8 min). Moreover, experienced technicians were more satisfi ed with skin scraping. Conclusion: Potassium hydroxide preparation of skin scrapings is an effective, time saving and practical technique to detect Demodex mites with accuracy comparable to the standard biopsy method.

Demodicidosis en niños: serie de 17 casos / Demodicidosis in children: a series of 17 cases

Introducción: Los ácaros Demodex folliculorum y Demodex brevis son ectoparásitos habituales en la unidad folículo-sebácea de los humanos, fundamentalmente en adultos. En niños inmunocompetentes su presencia es rara. El objetivo de nuestro estudio es describir y caracterizar la demodicidosis en niños. Material y métodos: Se seleccionaron pacientes menores de 15 años con manifestaciones clínicas sugerentes de demodicidosis. El diagnóstico se efectuó mediante la cuantificación de Demodex sp con KOH 30% bajo microscopía de luz. Resultados: Se reclutaron 17 casos, 16 pacientes de sexo femenino, todos con lesiones faciales características. Sólo en 3 pacientes hubo inmunosupresión concomitante. Todos los casos respondieron al tratamiento con permetrina 5% tópica. Conclusión: La demodicidosis infantil puede presentarse en pacientes inmunocompetentes, su diagnóstico requiere un alto índice de sospecha. Se observa una excelente respuesta con permetrina 5% tópica.

Introduction: The mites Demodex folliculorum and Demodex brevis are common ectoparasites in the follicle-sebaceous unit of humans, principally in adults. In immunocompetent children their presence is rare. The aim of our study is to describe and characterize the demodicidosis in children. Materials and methods: Patients under 15 years old with clinical manifestations suggestive of demodicidosis were selected. Diagnosis was made by quantification of Demodex sp with KOH 30% under light microscopy. Results: We found 17 cases, 16 females, all with typical facial lesions. Only 3 patients presented concomitant immunosuppression. All cases responded to topical 5% permethrin treatment. Conclusion: Infantile demodicidosis can occur in immunocompetents patients, and it diagnosis requires a high index of suspicion. An excellent response with topical 5% permethrin is observed.

Tinea Faciei-like Demodicidosis / 대한피부과학회지

Demodex folliculorum is a common mite of the pilosebaceous unit. Usually demodex infestation does not lead to the manifestation of pathologic skin diseases. But, in specific environments such as immunologic deficiency, they can proliferate and provoke cutaneous lesions. A 58-year-old patient presented with multiple, erythematous, annular-shaped plaques on the nose and right cheek. He had a 9-year history of Sjogren disease and she was treated with oral steroids and methotrexate. We found numerous Demodex folliculorum mites through a KOH microscopic examination and histologic examination of the right cheek. Biopsy resultd revealed that Demodex folliculorum mites were contained in the dilated follicular infundibulum. We diagnosed this case as an unusual manifestation of a Demodex infestation in a patient with Sjogren disease. We report an annular plaque-forming demodicidosis treated successfully with metronidazole.

Unilateral Demodicidosis in a Patient with Seborrheic Dermatitis / 대한의진균학회지

Demodex mites are considered part of the normal skin flora. Typically, Demodex is harmless and causes no clinical symptoms. We present a 43-year-old woman with pruritic erythematous plaque and papulopustular eruptions on the right cheek. The patient was treated seborrheic dermatitis in face from several years ago. However, the lesion was aggravated after continuous topical steroid usage for several months at a local clinic. Histological examinations revealed Demodex mites in the follicular ostia with perivascular and perifollicular lymphohistiocytic inflammation. Treatment was initiated with metronidazole at a dose of 250 mg three times per day and then crotamiton ointment once daily. The lesion showed marked improvement after six weeks of treatment with mild residual erythema. The findings presented here indicate that Demodex infestation should be considered in the differential diagnosis of unilateral follicular eruptions of the face.

A Case of Unilateral Demodicidosis / 대한피부과학회지

Demodex folliculorum is an obligate parasite of the human pilosebaceous follicle. Its etiological role of several skin diseases, such as rosacea, perioral dermatitis, and blepharoconjunctivitis, has been described in the dermatologic literature. A 39-year-old woman presented with erythematous, scaly, papulopustular eruption on the right side of her face. Many Demodex mites were found in the follicles of the affected area. The diagnosis of unilateral demodicidosis was established. Demodicidosis can present with a unilateral distribution, therefore, it should carefully be considered against the differential diagnosis of unilateral follicular skin lesions of the face.

Experimental and Clinical Studies on the Effect of Sodium Dodecylbenzene Sulfonate in in vitro Killing Demodex and in Treating Demodicidosis / 中国寄生虫学与寄生虫病杂志

Objective To observe the effect of sodium dodecylbenzene sulfonate (SDBS) in killing Demodex in vitro and in the treatment of demodicidosis. Methods ① The experiment of in vitro killing Demodex with 1% and 2% SDBS was conducted. ② A clinical trial was carried out to evaluate the therapeutic effect in the treatment of demodicidosis with 2% SDBS and 2% metronidazole emulsion. Patients with demodicidosis were randomly divided into trial and control groups (31 cases each). They were treated with 2% SDBS ointment and 2% metronidazole ointment twice a day in the early morning and evening respectively for eight weeks consecutively. Inflammatory lesions of face, Demodex infestation and scores of erythema were measured to evaluate the effect before and after treatment. ③ Follow-up was carried out for two months to evaluate the effect and side-effects after 8 weeks' treatment. Results ① 2% SDBS killed all Demodex in vitro after 5h, there was significant difference between the 2% SDBS and 2% metronidazole (69

Effect of Dibutyl Phthalate on Demodicidosis / 中国寄生虫学与寄生虫病杂志

Objective To evaluate the curative effect and safety of dibutyl phthalate on demodicidosis. Methods A single blinded and controlled study of human demodicidosis treated with dibutyl phthalate was conducted. One hundred and forty three patients with demodicidosis, including 81 acne and 62 rosacea, randomly divided into trial and control groups. The trial group was treated with dibutyl phthalate and control group with "new fumanling" cream twice a day in the early morning and evening respectively for six weeks consecutively. Results The rates of excellent, good, and fair efficacy and total effective rate in the trial group with acne were 53^7%, 41^5%, 4^9% and 100% respectively, with a significant difference to the control group (P0^05). No complaint of side effects in the trial group was recorded. Conclusion Dibutyl phthalate is highly effective to demodicidosis without prominent adverse reactions.