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Infectious Skin Diseases
Published in Aimilios Lallas, Zoe Apalla, Elizabeth Lazaridou, Dimitrios Ioannides, Theodosia Gkentsidi, Christina Fotiadou, Theocharis-Nektarios Kirtsios, Eirini Kyrmanidou, Konstantinos Lallas, Chryssoula Papageorgiou, Dermatoscopy A–Z, 2019
Aimilios Lallas, Zoe Apalla, Elizabeth Lazaridou, Dimitrios Ioannides, Theodosia Gkentsidi, Christina Fotiadou, Theocharis-Nektarios Kirtsios, Eirini Kyrmanidou, Konstantinos Lallas, Chryssoula Papageorgiou
Demodicosis is a common parasitic infestation that clinically manifests as erythema and papulopustules, combined with pruritus and a burning sensation. The most common site of involvement is the face (Figure 7.27). The responsible parasite is Demodex folliculorum. Demodex folliculorum is normally present on the human skin and remains nonpathogenic in many individuals. However, under certain circumstances, excessive proliferation of the parasite may result in demodicosis. The disease may clinically mimic periocular and perioral dermatitis, seborrheic dermatitis, acne vulgaris, and discoid lupus erythematosus from which it should be differentiated.
Bacterial and parasitic infections
Published in Aimilios Lallas, Enzo Errichetti, Dimitrios Ioannides, Dermoscopy in General Dermatology, 2018
Ignacio Gómez Martín, Balachandra Suryakant Ankad, Enzo Errichetti, Aimilios Lallas, Dimitrios Ioannides, Pedro Zaballos
Human demodicosis is a skin disease of the pilosebaceous units associated with human Demodex mites (Demodex folliculorum and Demodex brevis), which are widely known ectoparasitic mites mainly localized on the face.31 Such a condition can be classified into a primary form and a secondary form (associated with systemic or local immunosuppression).
Demodex and eye disease
Published in Clinical and Experimental Optometry, 2021
A diagnosis of facial demodicosis can be confirmed when five mites or more per cm2 (≥ 5/cm2) are found with a standardised skin‐surface biopsy.150 In contrast, ocular infestation has not been quantified by a recognised cut‐off or a standardised technique. The visualisation of CD66 and in situ lash manipulation techniques108,113,115 have facilitated diagnosis of the condition while performing routine biomicroscopy, but a severity scale or a demodicosis cut‐off has yet to be determined. Some have suggested that three or more mites at the root of the eyelash can be considered as infestation,139 others have proposed a severity scale with 10 lashes or more with CD considered to be a grade four severity,116 or even a scoring system with a cut‐off of four or more to begin treatment.117 Despite these proposals, none have been universally accepted. Total mite counts appear to be the most popular way of reporting prevalence35,39,40,46,47,81,95 while others report prevalence as mites per lash,41,66 or mites per subject.38 A validated scale of mite counts or index would be valuable to establish treatment initiation, determine infestation levels, study effectiveness of products and allow for study comparisons.
Non‐pharmaceutical treatment options for meibomian gland dysfunction
Published in Clinical and Experimental Optometry, 2020
Lid hygiene is also thought to be important because of the association of Demodex mites with MGD.2018 Long‐term practice of lid hygiene is necessary in individuals with Demodex infestation as it is a chronic condition that requires chronic therapy. Demodex folliculorum and Demodex brevis are thought to be the most common ectoparasites in humans. In the eye, D. folliculorum is found preferentially in the lash follicles and D. brevis in lash sebaceous glands.1981 There is a strong association between ocular demodicosis and ocular surface inflammatory conditions such as blepharitis, chalazia, and keratitis as well as MGD.2019 The pathogenesis of Demodex infestation has remained unclear;2000 however, this is in part because demodicosis has a high age‐dependent prevalence and is present frequently in asymptomatic individuals.2010
Evaluation of the effect of 577-nm pro-yellow laser on demodex intensity
Published in Journal of Cosmetic and Laser Therapy, 2021
Nihal Altunisik, Dursun Turkmen, Serpil Sener
Human Demodex mites (Demodex folliculorum and brevis) are commensal ectoparasites with a 14–18 day long life cycle, especially in the facial skin pilosebaceous unit and eyelashes. In children, the density of mite increases with age due to low sebum production and it is generally <5/cm2. The main nutritional source is follicular and glandular epithelium cells and sebum. Demodex species can sometimes be opportunistic pathogens in some cases although they have no pathogen effects. It is thought that they play a role in the pathogenesis of various diseases when they increase in number (≥5/cm2) or penetrate to the dermis. The skin disease of the pilosebaceous unit created by demodex mites is called demodicosis. Some authors classify demodicosis as primary and secondary. Absence of an inflammatory dermatosis before or during, increased demodex colonization in the lesions and reduction in symptoms with acaricidal therapy is defined as primary demodicosis. Presence of skin lesions with the increase in the number of demodex in some skin diseases is called secondary demodicosis. When the skin barrier breaks down, demodex antigens activate the immune system with Toll like receptor. In addition, demodex mite has been shown to causegranulomatous reaction when it crosses the follicular wall and penetrates to the dermis. While a great number of methods such as cellophane tape preparation, examination of pustule or skin scraping with potassium hydroxide (KOH) and dermoscopic examination are used in the diagnosis of demodicosis, standard superficial skin biopsy (SSSB) is the most preferred method in daily practice (1–4).