Cutaneous Manifestations of Parasitic Infections in HIV/AIDS
Clay J. Cockerell, Antoanella Calame in Cutaneous Manifestations of HIV Disease, 2012
Demodex folliculorum and D. brevis are the species of Demodex mites known to inhabit human hair follicles and pilosebaceous glands, obtaining sustenance from sebum. Demodex mites infest nearly 100% of the adult population, but may be pathogenic in HIV-positive patients. Though younger persons may not produce enough sebum to be adequate hosts, there are reported cases of demodicidosis in children. In one study of folliculitis in HIV-infected persons, Demodex mites were reported to be present in one-third of biopsies, with no correlation in distribution to the type of folliculitis.11 However, it is reasonable to assume a similar rate of infestation among adults, regardless of HIV status. Worsening health status may simply increase susceptibility of developing clinical disease due to mite infestation.
Acne, rosacea and similar disorders
Ronald Marks, Richard Motley in Common Skin Diseases, 2019
The cause of rosacea remains uncertain. Historically, dietary excess, alcoholism, gastrointestinal inflammatory disease, malabsorption and psychiatric disturbance have all been thought to be responsible, but controlled studies have failed to implicate these agencies. It is interesting to note that in the past 20 years gastrointestinal colonization by the microorganism Helicobacter pylori has been suspected (but not confirmed) of having a role in the aetiopathogenesis. The role of the mite Demodex folliculorum, a normal commensal of the hair follicle, is also unclear. Although it is found in vastly increased numbers in rosacea, this increase may result from the underlying disorder in which there is follicular distortion and dilatation. The mite is a normal inhabitant of adult facial hair follicles but it does not seem to do any harm.
Differential diagnoses of psoriasis
M. Alan Menter, Caitriona Ryan in Psoriasis, 2017
Rosacea is a chronic inflammatory disorder of the facial skin characterized by transient or persistent facial flushing, erythema, telangetasia, and often papules and pustules, typically involving the central face (nose, forehead, cheeks, and chin).99 Subtypes of rosacea include erythematotelangiectatic rosacea, papulopustular rosacea, phymatous rosacea, and ocular rosacea.99 Rosacea is a common disease, considered more common in fair-skinned individuals.100 Women are more affected than men. It is most common from 30 to 50 years of age, but can be seen in all ages.100 The development of rhinophyma is more common in men.100 Etiology remains unknown. Patients often report burning and erythema is triggered by irritants such as heat, sun exposure, alcohol, emotion, stress, hot drinks, and spicy food.99,100 Histopathology shows dilated superficial capillaries, solar elastosis with variable inflammation from mild perivascular lymphohistiocytic infiltrate to perifollicular, and perivascular infiltrate in papular rosacea.100,101 Foreign-body giant cells may be observed.100,102 Some lesions can contain granulomas which can be epitheliod, elastolytic, or palisaded around altered collagen.100–102 Demodex folliculorum is often observed.100
Is the presence of Demodex folliculorum increased with impaired glucose regulation in polycystic ovary syndrome?
Published in Journal of Obstetrics and Gynaecology, 2020
Semra Eroglu, Murat Cakmakliogullari, Elcin Kal Cakmakliogullari
Demodex folliculorum, which is known as follicle mange factor in humans, is a mite that belongs to the Demodicidia family of prostigmata. It is 0.1–0.4 mmlong, fusiform-shaped, and has 4 pairs of legs and a large abdomen. Demodexfolliculorum mostly resides in the bottom parts of hairs on the face, hair follicles and in the skin fat-secreting glands of the skin in humans (Desch and Nutting 1972; Nutting 1976; Markell et al. 1992; Zeytun 2017). The infestation of the eyelash follicle occurring due to D. Folliculorum is called demodicosis (Topcu et al. 2005). The pathologic changes of Demodex infestations include the obstruction of the base of eyelash follicles and of the mouths of the sebaceous gland, reactive hyperkeratinization of the eyelids, epithelial hyperplasia and inflammatory reactions to the parasitic structure; the mites also play a role as a mechanical vector for bacterial infection (Roihu and Kariniemi 1998).
Therapeutic Effect of Intense Pulsed Light on Ocular Demodicosis
Published in Current Eye Research, 2019
XiaoZhao Zhang, Nan Song, Lan Gong
The study also showed that lid margin abnormalities and conjunctival congestion were significantly decreased 1 month and 3 months after IPL treatment. Some other explanations include facilitating expression by softening the meibum as a result of heat transfer to the eyelids and meibomian glands.33 It also demonstrated that meibum quality and MG expressibility decreased significantly 1 month and 3 months after IPL treatment. The study confirms the above hypotheses. From our point of view, the primary mechanisms for the treatment effect of IPL for eyelid disease include not only reduction in chronic inflammation, improvement of meibum outflow by reduction in eyelid margin telangiectasias, and softening of meibum as a result of heat but also direct killing of Demodex from eyelid lashes by the production of heat. Demodex folliculorum mites live in hair follicles and sebaceous glands and often coexist with the bacillus oleronius bacterium. These organisms are known to cause an inflammatory response and have been linked to blepharitis and blepharokeratoconjunctivitis. Eradicating Demodex mites would have the indirect effect of decreasing the bacterial load on the eyelids, reducing the immune response and relieving symptoms associated with the eyelid margin and ocular surface.34
Latent Demodex infection contributes to intense pulsed light aggravated rosacea: cases serial
Published in Journal of Cosmetic and Laser Therapy, 2019
Peiru Wang, Linglin Zhang, Lei Shi, Chao Yuan, Guolong Zhang, Xiuli Wang
For the treatment of rosacea, IPL, laser, red, and blue light played an important part. Especially, IPL and pulsed dye laser on telangiectasia and persistent erythema treatment achieved good results(1,2,5,6). Some scholars suggested that IPL should be applied after inflammatory lesions relieved. For acne vulagris treatment, IPL can improve inflammatory papules of acne (7,8). IPL can invoke rosacea which has been buzzed through patients and doctors. These two cases presented rosacea exacerbation in 6–24 h. Both cases detected many Demodex. One of the possibilities is Demodex infection. Intense light irritation may make large amount of Demodex folliculorum sensitive, temporary active, or death in one time, thus stimulating the acute inflammatory response. The Demodex infection symptoms had not been found before IPL, which may be due to suppressed inflammation caused by topical tacrolimus. These two patients were also treated with topical tacrolimus for more than 2 weeks. One of the patients treated with IPL after Demodex infection got relieved and did not show rosacea exacerbation, which confirm our hypothesis. Heat may also aggravate rosacea. During and after treatment, cooling treatment was applied and the patients did not feel heat or burn. And the patient treated with IPL again did not show rosacea worse.
Related Knowledge Centers
- Blepharitis
- Commensalism
- Demodicosis
- Innate Immune System
- Parasitism
- Rosacea
- Type IV Hypersensitivity
- Vernix Caseosa
- Biological Life Cycle
- Sebaceous Gland
- Type IV Hypersensitivity