Search

Great Crested Flycatchers (Myiarchus crinitus), migratory passerines with a breeding range throughout the northeastern, midwestern, and southern US, are banded annually at the Braddock Bay Bird Observatory located on the southern shore of Lake Ontario, New York, USA. In 2016, a Great Crested Flycatcher was observed with distinct lesions in the gular and ventral neck region, which prompted evaluation for similar lesions in subsequently trapped flycatchers and other passerine species. From 2016 to 2023, 62/102 banded Great Crested Flycatchers had their gular region examined, and seven were found to have lesions (11.3% incidence). Similar lesions were not found in any other species. Lesions were localized to the gular region and included extensive feather loss with thickened, corrugated, pale-yellow skin. Grossly visible 1- to 2-mm-diameter, raised, white-to-yellow foci throughout the affected region corresponded microscopically to feather follicles that were massively dilated with mites. Morphologic analysis of mites obtained from skin scrapes revealed that this mite species belongs to the family Harpirhynchidae. Mites in this family have restricted avian host ranges and cause varying clinical presentations in passerines, though many species remain unidentified. PCR efforts were unsuccessful in yielding a species-level identification. Further monitoring of Great Crested Flycatchers and other avian species is warranted, as the fitness implications of this ectoparasitism at the individual and population levels are not known., (© Wildlife Disease Association 2024.)

The aim of work is description of new observations related to the participation of demodex in tumor morphogenesis with goal to study the example of eyelid papilloma, imagine the connection between the presence of the demodex mite and certain changes in the typical histomorphological picture of the neoplasm., Materials and Methods: Histomorphological examination covers biopsy and operative material of eye pathology with diagnosis of neoplasm (eyelid papilloma and actinic keratosis (senile keratosis, senile keratoma, solar keratosis)) were selected, with special attention paid to the presence of horn cysts. Agile methodologies were employed to manage the research workflow effectively., Results: As a result of the conducted histomorphological examination, in 24 cases (48%), patterns pathognomonic for demodectic infection were found. Such patterns, which could indicate the presence of a demodex mite, were cystic formations, as well as fragments of a dead parasite. We noted their presence not only in the tumor tissue, but also in the adjacent hair follicles, sebaceous glands, and subepidermal stroma. It is no coincidence that the authors who previously noted the presence of pigmented elements in keratopapillomas or seborrheic keratomas could not explain their origin, resorting to putting forward such fantastic assumptions as the presence of "symbiosis of melanoblasts and epithelial cells, which ensures the transfer of pigment from the first to the second"., Conclusions: Histomorphological study of serial sections allows us to see the successive stages of transformation of cavity intratissue defects created by the activity of the mite into horn cysts. Cavity defects are the main evidence of demodectic infestation. They occur in basal cell and squamous cell carcinomas, xanthomas, sebaceous adenomas, etc. tumors of the eyelids, but only in keratoacanthomas and senile keratomas they can turn into corneal cysts, which can be assumed to be due to the differentiating potential of these neoplasms.

Scabies is an important skin disease in several species of domestic and wild animals; however, few reports in Brazil have emphasized its occurrence in buffaloes. This article describes the epidemiological, clinical and pathological aspects and diagnosis of psoroptic mange in buffaloes in a property in the municipality of Castanhal, PA, Amazon region. Of the 41 buffaloes examined, 38 males and females of the Murrah, Baio, Mediterranean and Carabao breeds and their crossbreeds, aged between 2 and 20 years, had a history of pruritus. Clinical examination was performed to map the lesions, skin scrapings were collected to identify the mites, and a biopsy was performed for histopathological examination. Clinical signs, from mild to severe intensity, varied according to the system of creation and handling of the animals and were more severe in buffaloes raised in bays than those raised under a collective regime (pastures and collective troughs). The characteristic clinical signs were intense itching, extensive areas of alopecia, periocular edema, and thickening of the epidermis with exudative crusts covering the face, chamfer, neck, scapular region, back, base of the horn, thoracic and pelvic limbs and chest. The behavior of rubbing the affected regions of the body against structures (troughs, fence posts, gates) or with the horns was frequently observed and provided relief from itching. In the most severe cases, mites were also noted in the crusts, which were identified as Psoroptes natalensis. Histological skin lesions exhibited alterations consistent with immune-mediated dermatitis, which is typical of hypersensitivity to mite-derived allergens., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Rosacea is a chronic cutaneous disease that manifests with facial erythema, telangiectasia, papules and pustules on the central face. Although the pathogenesis is not well established, rosacea appears to have a close relationship with Demodex mites. The aim of the study was to elucidate the factors influencing Demodex mite density by standardized superficial skin biopsy (SSSB) in patients with rosacea. This prospective, cross-sectional study included 200 patients with rosacea. Clinical characteristics of the patients were recorded and SSSB was used to measure Demodex density (Dd). If Dd was < 5 D/cm 2 in the first SSSB, SSSB was repeated 4 more times to avoid false negative results. Of 200 patients, 152 (76%) were females and 48 (24%) males with a mean age of 43.47 ± 11.87 years. Ninety-nine patients (49.5%) had erythematotelangiectatic (ETR) and 101 patients (50.5%) had papulopustular (PPR) subtype of rosacea. Among 200 patients, the ratio of cumulative positive results of the consecutive SSSBs were as follows: 1st SSSB = 125 (62.5%), 2nd SSSB = 155 (77.5%), 3rd SSSB = 170 (85%), 4th SSSB = 173 (86.5%) and 5th SSSB = 174 (87%). The ratio of detecting Demodex infestation in the first SSSB was significantly lower in patients with PPR (55/101, 54.5%) than in patients with ETR (70/99, 70.7%). Median total Demodex mite density and D. folliculorum density were significantly higher in the ETR group than in the PPR group. There was a statistically significant relationship between density of Demodex tails in dermoscopy and positive/negative results of Demodex infestation in SSSB. As a conclusion, Demodex mite density by SSSB was influenced by various factors such as subtypes of rosacea, types of Demodex species, and dermoscopic findings., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Rosacea is a chronic inflammatory dermatological condition in humans, and its pathogenesis remains unclear. However, the development of rosacea is suspected to be related to Demodex, a microscopic commensal organism that resides in or near hair follicles and sebaceous glands. Although Demodex is known to be a host-specific, obligate commensal organism, it is currently difficult to be cultured in vitro to parasitize and infect other animal hosts. Therefore, direct evidence for a pathogenic role of Demodex in rosacea is currently lacking., Summary: As circumstantial evidence, non-invasive skin-detecting techniques have shown abnormally elevated numbers of Demodex in rosacea patients. Increased cytokine levels such as IL-10, IL-8, and IL-12p70 have been observed in human sebocytes following the Demodex challenge, and acaricides have been found to be effective in rosacea therapy, all point to a close relationship between Demodex and rosacea. Based on these findings, we conducted a comprehensive literature review to summarize the current state of knowledge, research insights, and clinical treatment recommendations for Demodex-associated rosacea, with the ultimate goal of improving patient outcomes., (© 2023 S. Karger AG, Basel.)

Psoroptes ovis, a common surface-living mite of domestic and wild animals worldwide, results in huge economic losses and serious welfare issues in the animal industry. P. ovis infestation rapidly causes massive eosinophil infiltration in skin lesions, and increasing research revealed that eosinophils might play an important role in the pathogenesis of P. ovis infestation. Intradermal injection of P. ovis antigen invoked massive eosinophil infiltration, suggesting that this mite should contain some relative molecules involved in eosinophil accumulation in the skin. However, these active molecules have not yet been identified. Herein, we identified macrophage migration inhibitor factor (MIF) in P. ovis ( Pso MIF) using bioinformatics and molecular biology methods. Sequence analyses revealed that Pso MIF appeared with high similarity to the topology of monomer and trimer formation with host MIF (RMSD = 0.28 angstroms and 2.826 angstroms, respectively) but with differences in tautomerase and thiol-protein oxidoreductase active sites. Reverse transcription PCR analysis (qRT-PCR) results showed that Pso MIF was expressed throughout all the developmental stages of P. ovis , particularly with the highest expression in female mites. Immunolocalization revealed that MIF protein located in the ovary and oviduct of female mites and also localized throughout the stratum spinosum, stratum granulosum, and even basal layers of the epidermis in skin lesions caused by P. ovis . r Pso MIF significantly upregulated eosinophil-related gene expression both in vitro (PBMC: CCL5, CCL11; HaCaT: IL-3, IL-4, IL-5, CCL5, CCL11) and in vivo (rabbit: IL-5, CCL5, CCL11, P-selectin, ICAM-1). Moreover, r Pso MIF could induce cutaneous eosinophil accumulation in a rabbit model and increased the vascular permeability in a mouse model. Our findings indicated that Pso MIF served as one of the key molecules contributing to skin eosinophil accumulation in P. ovis infection of rabbits.

Demodex mites are commensal parasites of hair follicles (HFs). Normally asymptomatic, inflammatory outgrowth of mites can accompany malnutrition, immune dysfunction, and aging, but mechanisms restricting Demodex outgrowth are not defined. Here, we show that control of mite HF colonization in mice required group 2 innate lymphoid cells (ILC2s), interleukin-13 (IL-13), and its receptor, IL-4Ra-IL-13Ra1. HF-associated ILC2s elaborated IL-13 that attenuated HFs and epithelial proliferation at anagen onset; in their absence, Demodex colonization led to increased epithelial proliferation and replacement of gene programs for repair by aberrant inflammation, leading to the loss of barrier function and HF exhaustion. Humans with rhinophymatous acne rosacea, an inflammatory condition associated with Demodex, had increased HF inflammation with decreased type 2 cytokines, consistent with the inverse relationship seen in mice. Our studies uncover a key role for skin ILC2s and IL-13, which comprise an immune checkpoint that sustains cutaneous integrity and restricts pathologic infestation by colonizing HF mites., Competing Interests: Declaration of interests R.M.L. is a member of the Scientific Resource Board at Genentech and serves on the Advisory Board at Immunity., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objective: An increase in the counts of the Demodex mites that exist in the microbiota of healthy individuals may lead to some dermatological diseases. This study aimed to investigate the prevalence of Demodex spp. among patients diagnosed with acne vulgaris, rosacea, perioral dermatitis, seborrheic dermatitis, eczema, and pityriasis folliculorum and the relationship between the demographic and clinical data of such patients and Demodex ., Methods: This study included 144 patients (70 with acne vulgaris, 6 with pityriasis folliculorum, 15 with seborrheic dermatitis, 39 with rosacea, 8 with eczema, and 6 with perioral dermatitis) and 73 healthy subjects. We evaluated Demodex positivity using the standard superficial skin biopsy method in all groups. The presence of more than five Demodex mites per square centimeter was considered positive at the diagnosis., Results: Of the 144 patients included in the study, 107 (74.3%) were female, and 37 (25.7%) were male, while 40 (54.8%) of the 73 healthy subjects were female, and 33 (45.2%) were male. Twenty-one patients (14.5%) and five of the healthy subjects (6.8%) tested positive for Demodex . We found that Demodex positivity rates in the rosacea and acne vulgaris groups were higher than in the control group. However, this level was not statistically significant (p>0.05). We found the highest positivity rate among the patient groups in the pityriasis folliculorum (4/6, 66.7%), rosacea (8/39, 20.5%), and perioral dermatitis (1/6, 16.7%) groups. Lastly, we found no statistically significant relationship between the demographic and clinical characteristics of the groups and Demodex positivity (p>0.05)., Conclusion: The present study is the only study that investigated Demodex positivity in six different dermatological diseases. Based on the results, we believe that investigating Demodex spp. positivity in dermatological diseases such as acne vulgaris, rosacea, and pityriasis folliculorum would be beneficial for early diagnosis and treatment.

Belgian Blue cattle are known for their high degree of muscling and good carcass qualities. This high degree of muscling is mainly caused by a mutation in the myostatin gene (MSTN). Although the MSTN mutation is considered as fixed in the Belgian Blue breed, segregation is occurring in a sub-population bred for dual purpose. In the latter population, we observed an association between the mutation in MSTN and susceptibility to psoroptic mange, a skin disease caused by Psoroptes ovis mites that heavily plagues Belgian Blue cattle. In total, 291 animals were sampled and screened for their susceptibility for mange lesions and their MSTN genotype. Via linear mixed modelling, we observed that homozygous mutant animals had a significant increase in the size of mange lesions (+2.51% lesion extent) compared to homozygous wild type. These findings were confirmed with zero-inflated modelling, an animal model and odds analysis. Risk ratios for developing severe mange lesions were 5.9 times as high for homozygous mutant animals. All analyses confirmed an association between the MSTN genotype and psoroptic mange lesion size., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

The aim of the study was to analyze the correlation between the presence of Demodex mites in the hair follicles of patients' eyelashes and the stability and break up time of the tear film assessed with the Non-Invasive Tear Break Up Times (NIBUT) method. 319 patients were included in the study (195 women, 124 men). The patients were divided into two groups: those with Demodex infestation and without visible symptoms of eyelid or eye surface diseases, and asymptomatic non-infested patients. The NIBUT analysis was performed with a 5 M keratograph (oculus). Non-invasive tests were performed to identify the first and mean values of the tear break up time. The first and mean tear break up time in the Demodex-infested group was lower than in the non-infested subjects. The difference was a highly statistically significant. There was a significant correlation with the age of the patients for the first break up time. The first break up time in both eyes decreased with the age of the Demodex-infested and non-infested patients. The NIBUT analyses indicate the impact of Demodex mites on the tear film stability. This may suggest possible association of demodicosis with dry eye syndrome., (© 2021. The Author(s).)

Purpose: Heterozygous missense STAT1 mutations leading to a gain of function (GOF) are the most frequent genetic cause of chronic mucocutaneous candidiasis (CMC). We describe the case of a patient presenting a new GOF mutation of STAT1 with the clinical symptoms of CMC, recurrent pneumonia, and persistent central erythema with papulopustules with ocular involvement related to rosacea-like demodicosis., Methods: Genetic analysis via targeted next-generation sequencing (NGS; NGS panel DIPAI v.1) exploring the 98 genes most frequently involved in primary immunodeficiencies, including STAT1 , was performed to identify an underlying genetic defect., Results: NGS identified a novel variant of STAT1 , c.884C>A (exon 10), p.T295Y, not previously described. This variant was found to be gain of function using an in vitro luciferase reporter assay. Rosacea-like demodicosis was confirmed by substantial Demodex proliferation observed via the microscopic examination of a cutaneous sample. A review of literature retrieved 20 other cases of STAT1 GOF mutations associated with early-onset rosacea-like demodicosis, most with ocular involvement., Conclusion: We describe a new STAT1 GOF mutation associated with a phenotype of CMC and rosacea-like demodicosis. Rosacea-like demodicosis appears as a novel and important clinical phenotype among patients with STAT1 GOF mutation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Martinot, Korganow, Wald, Second, Birckel, Mahé, Souply, Mohseni-Zadeh, Droy, Tarabeux, Okada, Migaud, Puel and Guffroy.)

Background: The dermoscopic findings of papulopustular rosacea include tiny papules and pustules, follicular plugs and follicular dilatation. Demodex tails and Demodex follicular openings are dermoscopic indicators that are mainly found in primary demodicosis and, less frequently, in rosacea., Aim: To describe the dermoscopic features of papulopustular rosacea and to investigate the differential dermoscopic features between patients with and without concomitant Demodex infestation., Methods: We conducted a prospective study of patients with almost-clear, mild or moderate papulopustular rosacea. For each patient, dermoscopic images were taken and a standardized skin surface biopsy was performed., Results: In this group of 60 patients, the most frequent dermoscopic findings were yellow dots, vascular polygons and follicular scales. Patients with moderate rosacea had more Demodex follicular openings compared with patients with mild rosacea (P = 0.02), while patients with mild rosacea had a higher frequency of follicular scales than did patients with almost-clear rosacea (P = 0.01). Patients with moderate rosacea had higher rates of Demodex follicular openings (P = 0.02), follicular scales (P < 0.001), follicular annular pigmentation (P = 0.001) and follicular pustules (P < 0.001) compared with patients with almost-clear rosacea. No significant dermoscopic differences were observed between patients with and without concomitant Demodex infestation., Conclusions: Papulopustular rosacea has specific dermoscopic findings. In our opinion, dermoscopy is not sufficient by itself for the diagnosis of Demodex proliferation in rosacea., (© 2021 British Association of Dermatologists.)

Our study evaluated the association between Demodex infestation and recurrent hordeola and examined the clinical features associated with these eyelid lesions. This was an observational, comparative study. We reviewed 250 patients and divided them into the recurrent hordeolum (n = 153) and control (n = 97) groups. Demodex infestation was detected by epilating eyelashes around the lesion/s and viewing them under a light microscope. Patient medical records and photographs were retrospectively analyzed to identify the clinical characteristics of Demodex-associated recurrent hordeola. Demodex was detected in 91 (59.5%) and 17 (17.5%) patients in the recurrent hordeolum and control groups (p < 0.001), respectively. In the recurrent hordeolum group, Demodex mites were found in 74 (68.5%) and 17 (37.8%) of the adult and pediatric patients (p < 0.001), respectively. Among patients with recurrent hordeola, patients in their 20s were most likely to have concomitant Demodex infestation. Patients with Demodex infestations were also more likely to develop recurrent lesions within a shorter period of time from the primary incision and curettage. The most common presentation of Demodex-associated recurrent lesions was external hordeola (67%) (p = 0.002). Demodex infestation may cause recurrent hordeola in adults and children. These mites may play a greater role in the development of lesions in adult patients. The strongest association between Demodex infestation and recurrent lesions was seen in patients in their 20s. Our results suggest that if the hordeola recur within a short period of time with the clinical characteristics of external location of eyelid, multiple numbers of lesions, or anterior blepharitis, eyelash epilation should be performed to identify the presence of Demodex mites., (© 2021. The Author(s).)

Purpose: To evaluate the efficacy of topical lotilaner ophthalmic solution, 0.25%, in patients with Demodex blepharitis. Methods: Eighteen adults with Demodex blepharitis, defined as >10 collarettes on the upper lid and/or mite density of ≥1.5 mites per lash (upper and lower), were treated bid for 42 days with the topical lotilaner ophthalmic solution, 0.25%. Contact lens wear, artificial eyelashes, and lid structural abnormalities were among the exclusion criteria. No other antibacterial, antiparasitic, or anti-inflammatory treatment or lid hygiene products were permitted. One eye of each patient was selected for analysis and assessed on day 7, 14, 28, and 42. Collarettes were graded at each visit, and mite density was evaluated by microscopy at each visit except day 7. Outcome measures were collarette elimination (≤2 lashes with collarettes) and mite eradication (0 mites). Drop tolerability, adverse events, visual acuity, and slit-lamp biomicroscopy were assessed. Results: Collarette elimination was achieved in 13/18 participants (72.2%) by day 42. Mean collarette grade (upper lid) declined from 3.56 ± 0.17 to 0.28 ± 0.11. Mite eradication was achieved in 14/18 participants (77.8%) by day 42. Mean mite density decreased from 2.63 ± 0.39 to 0.12 ± 0.08 mites/lash. Participants reported good tolerability. Adverse events were mild and transient and did not result in treatment discontinuation. Conclusion: Six weeks of at-home topical therapy with the lotilaner ophthalmic solution, 0.25%, was effective in eliminating the most common objective signs of Demodex blepharitis, with a collarette elimination rate of 72% and mite eradication in 78% of eyes by day 42. ISRCTN registration #: 24398865.

Avian knemidokoptosis, caused by knemidokoptid mites (Knemidokoptinae: Epidermoptidae), has been reported in wild and domestic birds globally. We report two cases of severe knemidokoptosis in Dunnocks (Prunella modularis) from separate sites in Great Britain, where the disease has previously been reported predominantly in finches and, less frequently, in corvids., (© Wildlife Disease Association 2021.)

Since its migration from the Asian honey bee (Apis cerana) to the European honey bee (Apis mellifera), the ectoparasitic mite Varroa destructor has emerged as a major issue for beekeeping worldwide. Due to a short history of coevolution, the host-parasite relationship between A. mellifera and V. destructor is unbalanced, with honey bees suffering infestation effects at the individual, colony and population levels. Several control solutions have been developed to tackle the colony and production losses due to Varroa, but the burden caused by the mite in combination with other biotic and abiotic factors continues to increase, weakening the beekeeping industry. In this synthetic review, we highlight the main advances made between 2015 and 2020 on V. destructor biology and its impact on the health of the honey bee, A. mellifera. We also describe the main control solutions that are currently available to fight the mite and place a special focus on new methodological developments, which point to integrated pest management strategies for the control of Varroa in honey bee colonies., (© 2020 The Author(s).)

Gamasoidosis is a poorly known and underdiagnosed mite infestation. It is characterized by the presence of erythematous and flattened papules that are quite pruritic, and can affect any region of the body, with preference for areas of folds. This article reports a case of the disease caused by mites of the species Dermanyssus gallinae. Increasingly, the agents that cause this disease are found in urban environments, increasing the incidence of people affected by the disease. This dermatosis has a self-limiting clinical picture and the treatment is done with the use of topical corticosteroids and oral antihistamines., (Copyright © 2020 Sociedade Brasileira de Dermatologia. Published by Elsevier España, S.L.U. All rights reserved.)

Background: Demodex mites are found on the skin of many healthy individuals. Demodex mites in high densities are considered to play a pathogenic role., Objective: To investigate the association between Demodex infestation and the three most common facial dermatoses: acne vulgaris, rosacea and seborrheic dermatitis., Methods: This prospective, observational case-control study included 127 patients (43 with acne vulgaris, 43 with rosacea and 41 with seborrheic dermatitis) and 77 healthy controls. The presence of demodicosis was evaluated by standardized skin surface biopsy in both the patient and control groups., Results: In terms of gender and age, no significant difference was found between the patients and controls (p>0.05). Demodex infestation rates were significantly higher in patients than in controls (p=0.001). Demodex infestation rates were significantly higher in the rosacea group than acne vulgaris and seborrheic dermatitis groups and controls (p=0.001; p=0.024; p=0.001, respectively). Demodex infestation was found to be significantly higher in the acne vulgaris and seborrheic dermatitis groups than in controls (p=0.001 and p=0.001, respectively). No difference was observed between the acne vulgaris and seborrheic dermatitis groups in terms of demodicosis (p=0.294)., Study Limitations: Small sample size is a limitation of the study. The lack of an objective scoring system in the diagnosis of Demodex infestation is another limitation., Conclusion: The findings of the present study emphasize that acne vulgaris, rosacea and seborrheic dermatitis are significantly associated with Demodex infestation. Standardized skin surface biopsy is a practical tool in the determination of Demodex infestation., (Copyright © 2020 Sociedade Brasileira de Dermatologia. Published by Elsevier España, S.L.U. All rights reserved.)

Pyemotes ventricosus mites are an uncommon cause of pruritic dermatitis seen most commonly in occupational exposure, prominently found in professionals such as farmers, landscapers, and factory workers who work with grains, wheat, dried beans, or grasses. The clinical description of the rash has typically been described as papular, erythematous, with a central vesicular lesion. We describe a case of Pyemotes dermatitis with an atypical clinical presentation. A 30-year-old man presented with pruritic, umbilicated papules, which involved his right lateral trunk and upper thigh leading to the submitted clinical impression of molloscum contagiosum. A biopsy of the skin was taken, and fragments of arthropod consistent with P. ventricosus were identified within umbilicated indentations of skin. The patient subsequently admitted to the onset of the rash immediately after carrying bales of straw while supporting each bale with his right side. The possibility of Pyemotes dermatitis mimicking a poxvirus-like eruption should be considered when encountering an unusual umbilicated papular eruption in the appropriate patient with occupational exposure.

Demodex mites are saprophytic parasites of the mammalian skin, mostly found in or near pilosebaceous units of hairy regions. While they can be found in healthy humans and animals without causing any clinical manifestations, they were suggested to create pathogenic symptoms when they appear in high densities under favourable conditions (ie, demodicosis). Nevertheless, their role as the primary causative agent of the pathogenic conditions in humans is debated today. Canine demodicosis, which is highly prevalent in certain dog breeds, provides a valuable tool for studying the pathogenesis of human demodicosis. Canine and human demodicosis are caused by different Demodex species, and the clinical manifestations in former could be life-threatening. Nevertheless, current literature suggests similar immune responses and immune evasion mechanisms in human and canine demodicosis; cellular immunity appeared to have a central role in protection against demodicosis, and Demodex mites were shown to influence both innate and adaptive immune response to escape immune attack. The aim of this review is to summarize the relevant literature on demodicosis obtained from studies conducted on both organisms, and draw the attention to the effect of mite-associated factors (eg, microbiota) on the different clinical manifestations displayed during human and canine demodicosis., (© 2019 John Wiley & Sons Ltd.)

To observe the clinical changes of meibomian gland dysfunctipn (MGD) and ocular Demodex infestation after intense pulsed light (IPL) treatment to further examine the mechanism of IPL treating patients with MGD and ocular Demodex infestation. The medical records of 25 patients (49 eyes) with MGD treated with IPL, were retrospectively examined to determine outcomes. Associated ocular-surface parameters (ocular surface disease index, OSDI; lipid layer thickness, LLT; noninvasive first breakup time, NIF-BUT; noninvasive average breakup time, NIAvg-BUT; tear film breakup area, TBUA; Schirmer I Test, SIT; corneal fluorescein staining, CFS), eyelid margin abnormalities, meibum quality and expressibility, MG morphological parameters (macrostructure and microstructure), and the number of Demodex infestation were examined before and after treatment. The MG microstructure and the Demodex infestation were examined via in vivo confocal microscopy (IVCM). The results showed that there were statistically significant differences in associated ocular-surface parameters (all P<0.05) before and after IPL treatment, except SIT (P=0.065). Eyelid margin abnormalities, meibum quality and expressibility obviously improved in upper and lower eyelid after IPL treatment (all P<0.0001). MG macrostructure (MG dropouts) decreased in upper (P=0.002) and lower eyelid (P=0.001) after IPL treatment. The nine parameters of MG microstructure in upper and lower eyelid all distinctly improved after IPL treatment (all P<0.0001). The mean number of Demodex mites on the upper lid margin (6.59±7.16 to 3.12±3.81/9 eyelashes) and lower lid margin (2.55±2.11 to 1.29±1.53/9 eyelashes) significantly reduced after IPL treatment (all P<0.0001). The Demodex eradication rate was 20% (8/40) in upper lid margin and 34.15% (14/41) in lower lid margin. These findings indicate that IPL shows great therapeutic potential for patients of MGD and ocular Demodex infestation.

Demodicosis is most frequently observed in the domestic dog (Canis familiaris), but it has rarely been reported in bats (Chiroptera). The overpopulation of Demodex spp. that causes dermatological changes is generally associated with a compromised immune system. We describe the gross and histological features of generalized demodicosis in an adult female African straw-coloured fruit bat (Eidolon helvum) drawn from a captive research colony. The histology of the lesions revealed comedones and follicular infundubular cysts harbouring numerous Demodex spp. mites, eliciting a minimal inflammatory response in the adjacent dermis. The histological examination of a full set of tissues did not reveal clear evidence of immunosuppression, although a clinical history of recent abortion and possible stressors due to captivity could be considered risk factors for the demodicosis. Attempts to determine the Demodex species using PCR on DNA extracted from the formalin fixed paraffin embedded tissue failed. This is the first clinical and histological description of demodicosis in Eidolon helvum.

Meibomian gland dysfunction (MGD) is a common disease in ophthalmic clinic. This study aimed to explore ocular Demodex infestation on the microstructure changes of the meibomian glands (MGs) in patients with MGD by in vivo confocal microscopy (IVCM).We retrospectively reviewed 103 eyes of 52 patients with MGD and 62 eyes of 31 non-MGD patients. All enrolled patients underwent IVCM examination. The following IVCM parameters were recorded: the MG acinar density (MAD), MG acinar longest diameter (MALD), MG acinar shortest diameter (MASD), MG orifice area (MOA), severity of MG fibrosis (MF), MG acinar irregularity (MAI), meibum secretion reflectivity (MSR), inhomogeneous appearance of walls of acinar units (AWI) and periglandular interstices of acinar units (API), and the number of Demodex.The positive rate of Demodex infestation in MGDs was 89.32%, and statistically higher than control group (controls; P < .001). All parameters showed statistically significant differences between MGDs and controls (P < .001), and Demodex-negative group and Demodex-positive group (P < .05) in both MGDs and controls, except MAD (P = .826) in controls. The number of Demodex was positively correlated with MALD, MASD, MF, MAI, MSR, AWI, and API in MGDs and controls (P < .05), and negatively correlated with MAD and MOA in MGDs (P < .05). MOA showed a strong significant correlation with the number of Demodex in controls (P < .001), whereas there was no significant difference between the number of Demodex and the MAD in controls (P = .448).Demodex can cause microstructural changes of MGs, which can cause or aggravate MGD, and the more the number of Demodex infestation, the more serious the structural damage.

Papulopustular rosacea and demodicosis are characterized by non-specific symptoms, which can make clinical diagnosis difficult. This retrospective study of 844 patients assessed the diagnostic importance of clinical signs and symptoms that are poorly recognized as being associated with these conditions. In addition to well-known signs (vascular signs (present in 80% of patients), papules (39%), pustules (22%) and ocular involvement (21%)), other signs and symptoms (discreet follicular scales (93%), scalp symptoms (pruritus, dandruff or folliculitis; 38%) and pruritus (15%)) may also suggest a diagnosis not only of demodicosis, but also of papulopustular rosacea. Facial Demodex densities (measured by 2 consecutive standardized skin biopsies) were higher when ocular or scalp involvement was present, suggesting more advanced disease, but further investigations are needed to confirm this hypothesis. Recognition of these clinical signs and symptoms should encourage dermatologists to perform a Demodex density test, thus enabling appropriate diagnosis to be made.

Background: Psoroptes cuniculi mites are the most common ear parasites infesting breeding female rabbits. The suffering rabbits show cutaneous signs of the infestation in the ears and are prone to secondary infections., Objectives: This trial was conducted to eliminate P. cuniculi in farm rabbits with a sustained-release ivermectin-loaded solid dispersion suspension (IVM-SD) suspension, and studied the stability of the formulation., Animals: There were 986 breeding female Hyplus rabbits naturally infected with P. cuniculi., Methods: All rabbits infected with P. cuniculi were subcutaneously administered with a single dose of IVM-SD suspension at 2 mg/kg body weight. Twenty-seven rabbits with severe infections were observed daily and examined on days 0 and 14 to score the lesions and count mites in crusts., Results: Fourteen days after the treatment no live mites were detected, demonstrating 100% therapeutic efficacy. The mean lesion scores decreased from 4.33 to 0.11 in the left ears and from 4.22 to 0.22 in the right ears. No reinfection occurred within 60 days of treatment., Conclusions: A single subcutaneous administration of the IVM-SD suspension at 2 mg/kg was effective in eliminating P. cuniculi infection in the rabbit farm.

Background: Rosacea is a common facial skin disorder mainly affecting middle-aged adults. Its aetiology is unknown and pathogenesis uncertain. Activation of the host innate immune response has been identified as an important factor. The Demodex mite population in the skin of rosacea patients is significantly higher than in patients with normal skin, suggesting that they may be of aetiological importance in this disorder., Objectives: To determine the potential of Demodex mites to interact with the host immune system., Methods: Live Demodex mites were extracted from normal facial skin of control subjects and used in cell stimulation experiments with the immortalized SZ95 sebocyte line. Time- and mite-dose-dependent experiments were performed. Direct effects of Demodex and effects of the medium in which Demodex had been cultured were evaluated on the Toll-like receptor (TLR) signalling pathway on both a gene and protein expression level., Results: Mites modulated TLR signalling events on both mRNA and protein levels in SZ95 sebocytes. An initial trend towards downmodulation of genes in this pathway was observed. A subsequent switch to positive gene upregulation was recorded after 48 h of coculture. Demodex secreted bioactive molecules that affected TLR2 receptor expression by sebocytes. High numbers of Demodex induced proinflammatory cytokine secretion, whereas lower numbers did not., Conclusions: Demodex mites have the capacity to modulate the TLR signalling pathway of an immortalized human sebocyte line. Mites have the capacity to secrete bioactive molecules that affect the immune reactivity of sebocytes. Increasing mite numbers influenced interleukin-8 secretion by these cells., (© 2018 British Association of Dermatologists.)

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease. This type of dermatosis with underlying chronic inflammation significantly affects the quality of life and may be accompanied by many comorbidities. In this case, Demodex spp. was associated with treatment-resistant and persistent course of skin diseases. A 46-year-old female patient applied to our clinic with complaints of lesions on the body and hip. Her dermatological examination revealed abscess formation and post-inflammatory pigmentation. Millimetric scar formation and improved folliculitis-like lesions were observed on both glutei. These complaints started 7 years ago and become more intense and severe by time. Owing to the diagnoses of diabetes mellitus, hypertension, and hyperlipidemia, the patient was monitored for metabolic syndrome. In the cultures taken from the lesions, no growth was seen. A standardized skin surface biopsy of the patient demonstrated demodicosis. The patient was treated with oral metronidazole and topical permethrin lotion, whereupon a pronounced recovery was observed in her clinical condition. In the light of this case, we recommend that patients with HS should be checked for the presence of Demodex spp., and if it is detected, an appropriate treatment should be applied. To our knowledge, this is the first case report presenting the relationship between HS and Demodex infestation.

Background: Papulopustular rosacea and rosacea-like demodicosis have numerous similarities, but they are generally considered as two distinct entities, mainly because the causal role of the Demodex mite in the development of rosacea is not yet widely accepted. Several clinical characteristics are traditionally considered to differentiate the two conditions; for example, papulopustular rosacea is typically characterized by central facial papulopustules and persistent erythema, whereas small superficial papulopustules and follicular scales rather suggest rosacea-like demodicosis. However, none of these characteristics is exclusive to either entity., Objective: To explore differences in Demodex densities according to clinical characteristics traditionally associated with these two conditions., Methods: Retrospective, observational, case-control study of 242 patients with central face papulopustules. Demodex densities were measured on two consecutive standardized skin surface biopsies., Results: In the whole cohort, Demodex densities were greater in patients with persistent erythema than in those without. In 132 patients without recent treatment or other facial dermatoses, 120 (91%) had persistent erythema, 119 (90%) small superficial papulopustules and 124 (94%) follicular scales; 116 (88%) simultaneously had clinical characteristics traditionally associated with both papulopustular rosacea and rosacea-like demodicosis. Higher Demodex densities were linked to the presence of follicular scales, but not to papulopustules size, nor to the presence/absence of persistent erythema., Conclusion: Our observations highlight the difficulty differentiating between these entities and suggest that rosacea-like demodicosis and papulopustular rosacea should no longer be considered as two separate entities, but rather as two phenotypes of the same disease., (© 2018 The Authors. Journal of the European Academy of Dermatology and Venereology published by John Wiley & Sons Ltd on behalf of European Academy of Dermatology and Venereology.)

Our study reports a case of acarodermatitis caused by Haemolaelaps casalis . By morphological observations, the mites seized were identified as Haemolaelaps casalis (deutonymph) which could attack humans resulting in acarodermatitis characterized with the symptoms of papules and blisters in different degrees. The patient was treated with 15% calamine lotion and anti-inflammatory and antipruritic drugs. Meanwhile, the mites were eliminated in the bedroom. After the treatment for one week, the patient was cured. Haemolaelaps casalis , which had been found in the indoor mattress, could attack humans and cause acarodermatitis. We should strengthen the work of anti-mite in domestic environment.

In infectious pathology, the gold standard consists of the detection of the pathogen within the sample. Identification of the pathogen is often difficult despite the presence of few and inexpensive tools, such, as special stain, immunohistochemistry, or in situ hybridization specific of the pathogen. In infectious pathology, there are morphological signs, which can guide us towards an etiology. We present some clinicopathological examples illustrating rare or unusual situations in cutaneous infectious pathology., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Background: Granulomatous rosacea is a rare chronic inflammatory skin disease with an unknown origin. The role of Demodex follicularum in its pathogenesis is currently proved., Case Presentation: We report a case of a 54-year-old Moroccan man with a 3-month history of erythematous, nonpruritic papules on the lateral side around the eyes. Dermoscopy and histology confirmed the diagnosis of granulomatous rosacea., Conclusions: We describe another clinical presentation of granulomatous rosacea with a clinical-dermoscopic-pathological correlation.

A 68-year-old Caucasian woman presented with a 1-month history of a facial and neck eruption (Figure 1A). Her face was covered with 3-mm monomorphic, pink, shiny, papules and rare pustules on an erythematous background. The eruption extended down the neck, her conjunctivae were injected, and her lid margins were inflamed. She had no history of rosacea.

Demodicosis is a rare condition that most often occurs in immunocompromised patients. We here describe a boy with T-cell non-Hodgkin lymphoma who developed a facial papulopustular eruption just before finalizing T-cell non-Hodgkin lymphoma treatment. He was treated for several infectious diseases without improvement. Demodicosis was considered and complete resolution was finally reached with topical metronidazole. We conducted a systematic search of all previously described cases of this condition in children with cancer, which showed that almost all demodicosis cases occurred in patients with lymphoreticular malignancies during maintenance chemotherapy. Hence, demodicosis may be seriously considered in antibiotic-resistant facial papulopustular eruptions in this group of patients to prevent delay of adequate treatment.

Competing Interests: Competing interests: None declared.

Pulmonary acariasis is a sporadic, incidental finding in colony-raised rhesus macaques (Macaca mulatta). Prophylactic treatment in indoor-raised and indoor-housed macaques is not routine due to low prevalence, lack of clinical significance, and potential risk of toxicosis. This case is an unusually severe infestation of Pneumonyssus simicola in an indoor-housed rhesus macaque, which ultimately resulted in this animal's death., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The honey bee, Apis mellifera, is a globally important species that suffers from a variety of pathogens and parasites. These parasites and pathogens may have sublethal effects on their bee hosts via an array of mechanisms, including through a change in symbiotic bacterial taxa. Our aim was to assess the influence of four globally widespread parasites and pathogens on the honey bee bacteriome. We examined the effects of the ectoparasitic mite Varroa destructor, the fungal pathogens Nosema apis and Nosema ceranae, and the trypanosome Lotmaria passim. Varroa was detected by acaricidal treatment, Nosema and L. passim by PCR, and the bacteriome using MiSeq 16S rRNA gene sequencing. Overall, the 1,858,850 obtained sequences formed 86 operational taxonomic units (OTUs) at 3 % dissimilarity. Location, time of year, and degree of infestation by Varroa had significant effects on the composition of the bacteriome of honey bee workers. Based on statistical correlations, we found varroosis more important factor than N. ceranae, N. apis, and L. passim infestation influencing the honey bee bacteriome and contributing to the changes in the composition of the bacterial community in adult bees. At the population level, Varroa appeared to modify 20 OTUs. In the colonies with high Varroa infestation levels (varroosis), the relative abundance of the bacteria Bartonella apis and Lactobacillus apis decreased. In contrast, an increase in relative abundance was observed for several taxa including Lactobacillus helsingborgensis, Lactobacillus mellis, Commensalibacter intestini, and Snodgrassella alvi. The results showed that the "normal" bacterial community is altered by eukaryotic parasites as well as displaying temporal changes and changes associated with the geographical origin of the beehive.

Diagnosing papulopustular rosacea is not always straightforward; no specific diagnostic test is currently available. A high density of Demodex mites is consistently observed in this condition. This retrospective study assesses an improved method for evaluating Demodex density among 1,044 patients presenting to our dermatology practice. The skin was cleaned with ether and Demodex densities were measured in 2 consecutive standardized skin surface biopsies taken from the same site. Mean densities in patients with rosacea and demodicosis were much higher than those in healthy controls and patients with other facial dermatoses. The optimal cut-off values for the 2 biopsies were combined and the resultant criterion (presence of a first biopsy density < 5 Demodex/cm2 or a second biopsy density < 10 Demodex/cm2) enabled confirmation of a diagnosis of rosacea or demodicosis with a sensitivity of 98.7% and specificity of 95.5%, making this a valuable diagnostic tool for dermatologists in routine clinical practice.

Numerous reports point to Demodex mites as the aetiology of certain eye and skin conditions, hence it is highly probable that infestation with these mites may also play a role in the aetiology and pathogenesis of pterygium. Therefore here we present a hypothesis: whether the presence of Demodex mites in eyelash hair follicles significantly correlates with the presence of pterygia, which could point to a potential role of these mites in the development of such lesions. We present preliminary data for supporting this hypothesis. These results were collected from a group of 69 subjects, including 39 with pterygium. Subjects were studied for the presence of Demodex folliculorum and/or D. brevis within eyelash follicles. The sample was defined as positive if at least one parasite, larva or egg were present. Preliminary statistical analyses were performed, and indicated a significant relationship between Demodex mite infestation and the presence of pterygium (p<0.05). This suggests that demodicosis could be one of the factors causing pterygium and significantly contribute to its development. Subjects who had both pterygium and Demodex infestation formed a dominant group. The proportion of subjects with both pterygia and Demodex presence is high at 93.33%, while the proportion of subjects without pterygia who have mites is low at 20.51%. Aforementioned results support our working hypothesis that infestation with Demodex mites may result in pterygium development and therefore patients diagnosed with pterygium should be assessed for the presence of Demodex to verify our preliminary results. In the present paper, we discuss potential influence of Demodex on conjunctiva and propose a hypothetical pathological mechanism linking the development of pterygia with demodicosis., (Copyright © 2016. Published by Elsevier Ltd.)

The purpose of this study was to determine subjective ocular symptoms occurring in patients infested with Demodex. The number of Demodex mites in the obtained material that correlated with the appearance of ocular symptoms was estimated. The study material were eyelashes collected from 1499 patients. The material were observed under a light microscope. T-test, the logistic regression method, and Pearson correlation coefficient were used for the analysis. Demodex mites were detected in 47% patients. The mean ages of infected women and men were 64 and 59 years, respectively. 64% infected patients complained of one or more ophthalmological symptoms. The most commonly reported symptoms included itching (28%), redness of eyelids (21%), and watery eyes (15%). Positive correlation was found between itching, redness, pain, purulence or eyelash loss and the presence of Demodex. The mentioned symptoms increase the probability of Demodex infestation in a statistically significant manner (p<0.005). A correlation between the age and gender and the number of Demodex was revealed by the study. The threshold average number of seven Demodex mites per eight collected eyelashes with which the risk of the occurrence of an ocular symptom increases significantly was defined. In patients with a low number of Demodex mites, symptoms may be absent. The risk of the occurrence of ocular symptom in patients with demodicosis increases with the increase in the average number of Demodex mites.

Demodicosis is a chronic skin disease caused by Demodex mites such as Demodex folliculorum and Demodex brevis. Demodex mites live in pilosebaceous units and they are regarded as a part of the normal skin flora. Nevertheless, it has been suggested that the presence of five or more mites per cm² by the standardized skin surface biopsy technique could be considered as pathogenic.

This paper reports the occurrence of porcine demodicosis caused by the mite Demodex phylloides in hogs reared in a peri-urban family farm located in Francisco Morato, a municipality of the Metropolitan Region of São Paulo, capital city of the state of São Paulo, Brazil. In a parcel of forty Landrace - Large White cross hogs, approximately four months old, four animals presented severe skin lesions in the form of small nodules over their entire body, especially in the periocular region, snout, lower abdomen and flanks. Two hogs had to be euthanized for animal welfare reasons, which enabled post-mortem examination. Skin scrapings revealed eggs, larvae, nymphs and adults of D. phylloides. Purulent subcutaneous nodules with intense parasitic folliculitis and intense perifollicular inflammatory reaction were present. Enterobacteria and coagulase-positive Staphylococcus spp. were isolated from the skin pustules. Necropsy revealed milk spotted liver, enteritis and enlargement of mesenteric lymph nodes. Protozoa (Eimeria spp. and Balantidium sp.), helminth eggs (Ascaris suum, Trichuris suis and strongyles) and Brachyspira spp. were found in faeces. Staphylococcus spp. and enterobacteria were isolated from internal organs. All remaining hogs were treated with ivermectin at a daily oral dose of 0.45g/kg of feed, during seven days. Fifteen days after treatment, remission of symptoms was observed in the surviving animals with demodicosis; absence of mites was confirmed by skin scraping examinations. The hogs were reared under poor environmental, nutritional and sanitary conditions, resulting in multimorbidity and immunosuppression. Severe clinical porcine demodicosis was triggered when the animals were castrated. Family pig farmers had been suffering economic losses due to the stunted growth of the herd. In addition to that, the lesions found on the skin and in the internal organs would result in condemnation of meat and viscera for human consumption. As part of a Public Policies Project, farm facilities were renovated with governmental aid, while family farmers received training. Good management practices and biosecurity measures were introduced in the herd. Educative policies and financial support were important to guide family pig farmers towards better husbandry practices, allowing them to raise healthy hogs in compliance with market demands., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Lynxacarus radovskyi (fur mites) are ectoparasites found on the hair shafts of cats living in tropical environments. Diagnosis is via microscopic examination of hairs. Various anatomical areas have been reported to harbour these mites., Objectives: To assess adhesive tape impressions and trichograms for detecting L. radovskyi and co-infestations; to determine host body predilection sites and affected gender; to determine prevalence of L. radovskyi in a feral cat population., Animals: 121 feral cats in a trap, neuter and release programme., Methods: After cats were premedicated for surgical sterilization, hairs from seven to nine body sites were removed from each cat using adhesive tape impression and trichogram techniques. Samples were examined at 10-100× magnification using compound or stereo microscopes., Results: The prevalence of L. radovskyi was 71% (86 of 121) within the feral cat population. Tape impressions identified 75 cats; trichograms identified 56 cats. There were fewer false negative results with tape impressions. Caudal body sites were more likely to be positive, with the perianal area being the most commonly affected. Males and females were infested equally. Tape impressions identified more Cheyletiella blakei infestations and both methods identified some Felicola felis infestations., Conclusions and Clinical Importance: Tape impressions were easier to perform and identified more L. radovskyi positive cats and more co-infestations. Hairs from the perianal area and other caudal body sites are most likely to harbour L. radovskyi. Within this feral cat population, L. radovskyi was a common infestation., (© 2016 ESVD and ACVD.)