Diverse clinical presentations of demodicosis: A clinicodermoscopic study

Intravitreal Triamcinolone

Demodex mites share a commensal relationship with humans, and they asymptomatically parasitize the pilosebaceous follicles of humans. In healthy skin, the density of the mites is normally low, and this low density does not cause skin diseases. When the density of these mites increases, they induce facial skin diseases. We describe a 27-year-old male who presented in our outpatient department with a 10-year history of red and itchy skin lesions on the right side of his face. Determination of the density of Demodex folliculorum on the right cheek by standardized skin surface biopsy (SSSB) revealed a density of 20 Demodex/cm.2 On the contrary, the left face revealed a density of 2 Demodex/cm^2 The density of D. folliculorum declined after treatment with oral metronidazole. The redness of the right cheek improved. Herein, we will introduce the method of modified SSSB, which will be more suitable and useful for Taiwan dermatologists in their daily practice.

Demodex mites are believed to contribute to the pathogenesis of both rosacea and demodicosis. While standardized skin surface biopsy (SSSB) remains the gold standard for detecting Demodex density, it is invasive and time-consuming. Ultraviolet (UV) dermoscopy, a non-invasive technique that visualizes fluorescent structures, may offer a rapid alternative for identifying Demodex proliferation. To investigate the relationship between Demodex folliculorum (D. folliculorum) and Demodex brevis (D.brevis) counts obtained by SSSB and fluorescent dots detected under UV dermoscopy, and to evaluate the diagnostic value of these findings in rosacea and demodicosis. Fifty-four patients with rosacea or demodicosis were evaluated using both UV dermoscopy and SSSB from the same facial region. Orange and bright blue fluorescent dots were recorded dermoscopically, and mite density and species were quantified via SSSB. Correlation analyses and ROC curve analysis were performed to assess diagnostic performance. A significant positive correlation was found between total Demodex count and bright blue fluorescent dots (r = 0.343, p = 0.013), but not with orange dots (r = -0.065, p = 0.649). Only D. folliculorum showed significant correlation with blue and total fluorescent dots. ROC analysis identified >11 bright blue dots as the optimal threshold for predicting Demodex positivity, with a sensitivity of 82.1% and specificity of 71.4% (AUC = 0.793, p = 0.003). Bright blue fluorescent dots observed under UV dermoscopy significantly correlate with Demodex density, particularly D. folliculorum. A threshold of >11 blue dots demonstrated good diagnostic accuracy and may serve as a practical, non-invasive alternative or adjunct to SSSB in clinical settings. Orange fluorescence was not associated with Demodex density and likely reflects unrelated sebaceous or microbial activity.

Funding sources: None. Conflicts of interest: None declared. Madam, We thank Lacey et al.1 for their interesting and very welcome thoughts concerning our article on the usefulness of confocal laser scanning microscopy (CLSM) in the quantification of Demodex mites, and for their excellent pictures of Demodex mites, seen under the light microscope after extraction using the standardized skin surface biopsy (SSSB) method. As a centre specialized in acne and rosacea we are also using SSSB routinely as the standard method for Demodex quantification and have gathered ample experience within the past decades. We agree that mainly Demodex folliculorum is detected with SSSB and especially with CLSM (with a penetration depth limited to about 200–300 μm), as D. folliculorum is usually located at the upper part of the infundibulum of the hair follicle, while Demodex brevis is usually seen at the lower portion close to the sebaceous glands. Thus D. brevis may be more frequently identified by SSSB, as well as the different life stages. This may be important in understanding the role of Demodex mites in human skin, but in our experience the main question in daily practice is: ‘Is the number of Demodex mites normal or are there too many?’ Our data suggest that CLSM offers a noninvasive and quick method to answer this question in vivo.2

Demodex blepharitis is a special form of blepharitis caused by Demodex.Demodex folliculorum and Demodex brevis that infect the eyelids are parasitic on the hair follicles and sebaceous glands, respectively.When the number of infections is large or local factors affect the hair follicle and meibomian glands, a series of clinical symptoms and signs are produced.The main diagnosis of Demodex blepharitis needs to combine clinical manifestations and Demodex detection.Patients with obvious symptoms and signs need timely treatment.This study reviewed the epidemiology, pathogenesis, pathological changes, clinical manifestations, diagnosis, treatment and prevention of vermicular blepharitis in order to provide reference for the research of Demodex blepharitis. Key words: Demodex folliculorum; Blepharitis; Epidemiology; Pathogenesis; Pathological changes; Clinical manifestations; Diagnosis; Treatment; Prevention; Tree tea oil

BackgroundDemodicosis is a parasitic skin disease caused by Demodex mites, and the determination of mite density per square centimeter is important to diagnose demodicosis. Standardized skin surface biopsy (SSSB) and direct microscopic examination (DME) are commonly used to determine Demodex mites density (Dd). However, no study has previously compared these two methods with respect to clinical types and distribution patterns of demodicosis.ObjectiveThe aim of this study was to compare the value of SSSB and DME findings in reference to the clinical types and distribution patterns of demodicosis.MethodsThe medical records of 35 patients diagnosed with demodicosis between December 2011 and June 2015 were retrospectively reviewed. Demodicosis was classified according to four clinical types (pityriasis folliculorum, rosacea type, acne type, and perioral type) and three distribution patterns (diffuse pattern, U-zone pattern, and T-zone pattern). Two samples, one for SSSB and one for DME, were obtained from a lesion of each patient.ResultsIn all patients, mean Dd and the proportion with a high Dd (>5D/cm2) by DME (14.5±3.3, 80.0%, respectively) were higher than by SSSB (5.5±1.3, 37.1%, respectively; p<0.01, p=0.02, respectively). In terms of clinical types, for rosacea type, mean Dd and proportion with a high Dd by DME (12.4±3.5, 84.6%, respectively) were significantly greater than those determined by SSSB (3.6±1.2, 23.1%; p=0.04, p=0.04, respectively). In terms of distribution pattern, for the diffuse pattern, mean Dd and the proportion with a high Dd by DME (17.5±3.7, 100%, respectively) were significantly higher than those determined by SSSB (6.0±2.7, 26.7%; p<0.01, p<0.01, respectively).ConclusionThe results of our study revealed that DME is a more sensitive method for detecting Demodex than SSSB, especially in patients with diffuse pattern and suspected rosacea type. Further research is needed to confirm this finding.

To assess the clinical and cost-effectiveness of once-daily use of topical corticosteroids versus more frequent use of same-potency topical corticosteroids in the treatment of people with atopic eczema. Electronic databases. Bibliographies of included studies and related papers. Experts in the field. Manufacturer submissions to the National Institute for Clinical Excellence. Studies were assessed for inclusion according to predefined criteria by two reviewers. Data extraction and quality assessment were undertaken by one reviewer and checked by a second reviewer. Clinical effectiveness data were synthesised through a narrative review with full tabulation of results. One RCT comparing moderately potent corticosteroids, eight RCTs comparing potent corticosteroids and one RCT comparing very potent corticosteroids were included. No RCTs or CCTs of mild corticosteroids were eligible. Most RCTs were of poor methodological quality, although two were judged to be of good quality. The only study that compared moderately potent corticosteroids found no significant difference between once- and twice-daily application. For potent corticosteroids, some statistically significant differences in numbers of patients responding to treatment were identified favouring twice-daily treatment, but these were inconsistent between physician and patient assessment and outcomes selected for analysis. Two studies found a significant improvement in some symptoms with once-daily mometasone furoate compared with twice-daily application of a different active compound, while a third study found no significant differences. One good-quality study favoured twice-daily application of fluticasone propionate ointment, while other studies found no significant difference or an improvement in one symptom but not others. The only study comparing very potent corticosteroids found a statistically significant difference in comparative clinical response in favour of three-times daily treatment, but no difference in number of patients with at least a good response. There appears to be little difference in the frequency or severity of short-term events, however data are limited. No published economic evaluations were identified. Given findings on clinical effectiveness, where outcomes from the comparators are similar, the relative cost-effectiveness of once-daily versus more frequent application of topical corticosteroids becomes a case of cost-minimisation, where the least-cost alternative should be favoured, all else being equal. Topical corticosteroid products included in this review have a wide variation in price; the cost per 30 g/30 ml varies between GBP0.60 and GBP4.88. Specific decisions on the least-cost alternative, between once-daily and more frequent application of products, will be determined by the relative price of the products being compared. Where patients can be appropriately prescribed once-daily treatment of a similarly priced product, a reduction in the quantity of topical corticosteroid used will be expected. However, issues related to pack size for prescribed products and subsequent waste (unused product) could easily erode any potential saving. The potential cost-savings on prescribed products are very small at a patient level; although given the large numbers of patients with atopic eczema, cost savings in theory could be substantial. The presence of specifically marketed 'once-daily' topical corticosteroids, which are relatively expensive (per unit price), may result in additional costs should there be a general recommendation in favour of once-daily use of topical corticosteroids, compared to more frequent use. The literature is very limited; that available indicates the clinical effectiveness of once-daily and more frequent application of potent topical corticosteroids is very similar, but it does not offer a basis for favouring either option. The cost-effectiveness of once-daily versus more frequent use will depend on the generalisability of the findings to the specific treatment decision and the relative product prices. The trials included in this review generally refer to moderate to severe atopic eczema, whereas most patients have mild disease, and furthermore most of the included trials report on potent topical corticosteroids (eight of 10 RCTs); therefore the generalisability of the findings is limited. Further research is required on the clinical and cost-effectiveness of once-daily versus more frequent use of same potency corticosteroids, specifically on mild potency products for mild to moderate atopic eczema. Outcomes should include quality of life and compliance.

Successful treatment of ivermectin refractory demodicosis with isotretinoin and permethrin cream

Demodicosis is the term applied to cutaneous diseases caused by Demodex folliculorum and Demodex brevis. Demodex mites are acquired shortly after birth. They are saprophytic ectoparasites that are found primarily in areas rich in sebaceous glands, like face, scalp, neck. While human demodicosis is a skin disease sui generis, it can mimic many other inflammatory dermatoses. Therefore demodicosis are commonly underdiagnosed, and are masked behind other diagnoses such as papulopustular rosacea, erythemato telangiectasic rosacea, seborrheic dermatitis, perioral dermatitis, contact dermatitis, atopic dermatitis, phyma, seborrhea, etc. Human demodicosis is classified into a primary and secondary form by Chen and Plewig. Absence of pre-existing or concurrent inflammatory dermatosis (acne, rosacea or perioral dermatitis), abnormal increase in mite colonization in active lesions, and remission of the lesions following adequate treatment with topical or systemic acaricides/arachnicides, but not with antibiotics with antiinflammatory effects are diagnostic criteria of primary demodicosis. Secondary demodicosis is defined to skin lesions associated with an abnormal increase of Demodex mites in patients with other known skin or systemic diseases. Clinically, demodicosis has a wide range of variants and may manifest as folliculitis (Pityriasis folliculorum), papulopustular erythema (Rosacea-like demodicosis), blepharoconjunctivitis (demodectic blepharitis), and granulomatous rosacea-like demodicosis (Demodicosis gravis) The pathogenesis of human demodicosis remains largely obscure Here, we discuss the clinical manifestations, pathogenesis of demodicosis, and treatment strategies.

Reflectance confocal microscopy (RCM) has been recently shown to be effective for measuring the Demodex mite density. To compare and demonstrate the advantages and disadvantages of standardized skin surface biopsy (SSSB) and RCM for measuring the density of Demodex mites. Forty-eight patients (30 female, 18 male) and 47 healthy controls (30 female, 17 male) were enrolled in the study. The patients diagnoses were pityriasis folliculorum (n=40), papulopustulary rosecea (n=7) and erythema-telengiectatic rosacea (n=1). The area with the most intense erythema on the right cheek was selected for imaging with RCM (VivaScope 3000) and SSSB. Forty-two patients demonstrated high Demodex density [(Dd)>5mites/cm(2) ] with SSSB (85.7%). RCM identified demodicosis in 48 patients (100%). The mean Dd measured with RCM (409.8±209.2) was significantly higher than SSSB (15.33±18.1) (P<0.001). In the patients, RCM demonstrated the mean number of mites 40.90±20.9 and 4.11±6.4 in the controls per 10mm(2) area. The corresponding mean number of 2.63±0.77 mites was detected in the infested follicles per area of view compared to a mean of 0.77±0.98 mites in the infested follicles in the controls (P<0.001). Reflectance confocal microscopy is a fast, direct and noninvasive method for Demodex-associated diseases and it is superior to SSSB for Demodex mite detection.

Vitiligo treated with topical corticosteroids: Children with head and neck involvement respond well∗

In daily dermatological practice, many dermatologists do not include demodicosis in their differential diagnoses, or the diagnosis of demodicosis is frequently masked by other skin diseases such as papulopustular or erythematotelangiectatic rosacea, seborrhoeic dermatitis, perioral dermatitis and contact dermatitis. There are two methods for measurement of the density of Demodex folliculorum (Dd): standardized skin surface biopsy (SSSB) and direct microscopic examination of fresh secretions from sebaceous glands (DME). No study has been reported in the literature comparing the diagnostic value of these two techniques. To compare the value of the two techniques, SSSB and DME, for the measurement of Dd in patients with suspected demodicosis. Mite density was investigated using SSSB and DME in 37 patients with facial skin lesions suggesting demodicosis. Two samples, one for SSSB and one for DME, were obtained from a cheek lesion of each patient. Twenty-three (62%) patients were diagnosed with demodicosis according to their clinical manifestations combined with a high Dd (Dd > 5 mites cm(-2)) with SSSB and/or DME. In all the patients, the mean Dd measured with SSSB was higher than that with DME (22.9 +/- 5.9 and 2.2 +/- 0.8, respectively; P = 0.001). Also, among the 23 patients with demodicosis, the mean Dd measured using SSSB was higher than the mean Dd with DME (36.5 +/- 8.3 and 3.4 +/- 1.2, respectively; P = 0.0001). We recommend the use of SSSB for the measurement of Dd as more patients with demodicosis can be diagnosed with this method compared with the DME method.

Demodex mites are highly found in the skin of patients with rosacea. The diagnosis of Demodex can be made by standardized skin surface biopsy. Dermoscopy is a tool used in the noninvasive diagnosis of various dermatological diseases. To determine whether dermoscopic features of demodicosis are associated with the result of standardized skin surface biopsy in patients with rosacea and to compare dermoscopic features of rosacea in Demodex-positive and negative samples and Demodex type. A total of 30 patients (7 male, 23 female) were included in the study. Dermoscopic examination was performed on both the clinically most severely affected areas and adjacent healthy skin. The skin surface biopsy sample was taken from the same place from where the dermoscopic image was taken. A total of 83 (lesion n = 60, non-lesion n = 23) areas were evaluated. Demodex was detected in 60.2% (n = 50) of the samples. Half of these samples revealed only Demodex folliculorum, and the remaining half revealed D folliculorum and Demodex brevis. Of the Demodex-positive samples, 88% had Demodex tails (P =0.001) and 68% Demodex follicular openings (P = 0.002) on dermoscopy. In D folliculorum+D brevis-positive samples, the rate of scale and pustule was higher than D folliculorum-positive samples (P = 0.017 and P = 0032, respectively). The sensitivity and specificity of Demodex tail are higher than Demodex follicular opening and scale and pustule detection with dermoscopy and may indicate the coexistence of both D folliculorum and D brevis.

Human Demodex mites (Demodex folliculorum and Demodex brevis) hold a high rank in the evolutionary and phylogenetic hierarchy of the skin microbiome, although in most people their presence is of no consequence. While human demodicosis is a skin disease sui generis, it can mimic many other inflammatory dermatoses, such as folliculitis, rosacea and perioral dermatitis, leading to unspecific and confusing descriptions in the literature. Here, we propose to classify human demodicosis into a primary form and a secondary form, which is associated mainly with immunosuppression. The clinical manifestations of primary demodicosis may include (i) spinulate demodicosis, currently known as pityriasis folliculorum, involving sebaceous hair follicles without visible inflammation; (ii) papulopustular/nodulocystic or conglobate demodicosis with pronounced inflammation affecting most commonly the perioral and periorbital areas of the face; (iii) ocular demodicosis, inducing chronic blepharitis, chalazia or, less commonly, keratoconjunctivitis; and (iv) auricular demodicosis causing external otitis or myringitis. Secondary demodicosis is usually associated with systemic or local immunosuppression. Treatment is only weakly evidence based, and the most effective concentrations of acaricides remain to be determined. Optimization of an in vitro or ex vivo culture model is necessary for future studies. Endosymbiosis between certain bacteria and Demodex mites in the pathogenesis of demodicosis deserves more attention. Further clinical observations and experiments are needed to prove our hypothesis.

Summary Introduction. Rosacea is a chronic disease characterized by (depending on the sub- type) facial prolonged erythema, sometimes pustules or nodules. Rosacea affects all ages and sex with four subtypes. Pathophysiology aims to many different trigger factors like sun exposure, emotional stress or changed intestinal flora. Studies about Demodex mites according to different authors revealed that they may play a role in rosacea exacerbation in particular along with other triggers. Aim. An attempt to determine the role of Demodex mites among patients with rosacea. Material and methods. The study included patients with rosacea from 22 to 63 years of age. The patient status and content of hair follicles were assessed during two visits in our outpatient clinic. During the first visit, detailed medical history was taken, phys- ical examination and hypoallergenic adhesive were applied (nose, chin, cheeks and forehead) in order to pursue the content of the sebaceous glands. During the second visit, patients qualified to the research were again examined while adhesives have been removed. By using stereoscopic microscope Stemi 2000, Demodex mites from hair fol- licles were analyzed. Results. Initially, contents from hair follicles of 38 patients with rosacea have been examined. The presence of Demodex was confirmed in 11 patients. Most cases of con- firmed Demodex infestation concerned patients with papulopustular rosacea. Live sub- jects were collected only from the ales and the decrease in their motility was observed over the course of time after the removal of plasters from the skin. Conclusions. Obtained results confirming the infestation of 11 out of 38 patients with erythematotelangiectatic rosacea indicates Demodex folliculorum as a direct or indirect pathogen. Based on the results, we can state that among our patients Demodex mites were not a main trigger factor. Standardized skin surface biopsy is not a sufficient screen- ing test.