Chronic blepharitis due to Demodex: A prospective study in Sfax (Tunisia).

INTRODUCTION: Chronic blepharitis is a common cause of eye irritation and dryness. They are often treated without regard to causal factors such as parasites which are rarely mentioned. AIM: To describe the role of Demodex in the pathogenesis of chronic blepharitis, to analyze the epidemiological, clinical, diagnostic and therapeutic particularities. METHODS: This is a prospective, case-control study conducted in the mycology parasitology department at the Habib Bourguiba university hospital in Sfax covering 100 cases with chronic blepharitis and 87 control cases. Clinical examination and eyelash removal were performed with direct examination for qualitative and quantitative analysis, before and after treatment. RESULTS: Demodex was significantly more found in patients than in controls (48% vs 13.8%). The quantitative analysis showed a significant difference between the two groups with 52.1% of Demodex (+++) for patients versus 8.3% for controls. Demodex blepharitis were treated with yellow oxid mercure ophthalmic ointment with a good outcome in 81,3%. CONCLUSION: Although it is admitted to be a saprophyte of the skin, a large number of arguments argues for the incrimination of Demodex in the etiopathogenesis of chronic blepharitis, hence the interest of eyelashes examination and a parasitic research in front of any chronic blepharitis resistant to usual treatments. In case of positive research, a specific treatment should be prescribed. Its effectiveness is another argument for the etiological diagnosis.

Double-Blind Comparison of Eyelash Epilation Techniques for the Purpose of Demodex folliculorum Mite Retrieval.

OBJECTIVE: Demodex folliculorum blepharitis is typically confirmed with lash epilation and microscopic identification of mites. However, mite counts may vary with the epilation technique. As there is no gold standard to epilating lashes for the purposes of mite counts, the aim of this study was to compare three epilation techniques. METHOD: A prospective randomized double-blind study compared three epilation techniques on lashes with cylindrical dandruff. Techniques included (A) direct pulling of the lash; (B) rotating the lash before epilation; and (C) sliding the cylindrical dandruff away, lash rotation, and epilation. Mean mite counts were analyzed using a repeated-measures analysis of variance. RESULTS: Forty (n=40) participants (20 M: 20 F, mean age of 62.3±17.1 years) revealed similar mite counts between right (1.43±1.74) and left (1.35±1.59) eyes ( P =0.63). A significant difference ( P =0.03) in mite count was noted (technique A: 1.05 ± 1.60; technique B 1.76 ± 1.80; and technique C 1.36 ± 1.54) with technique B yielding the highest mite count ( P =0.04). CONCLUSION: Demodex mite count is a key parameter in establishing infestation or to determine treatment efficacy. This study revealed that rotating the lash before epilation yielded the highest mite count. Future studies should report the epilation technique used to allow for study comparisons.

The effect of phototherapy on Demodex density: a case-control study.

BACKGROUND: Human Demodex mites, Demodex folliculorum and Demodex brevis, are microorganisms that reside in the pilosebaceous units, usually without causing symptoms. Phototherapy has been linked to demodicosis in previous studies. We aimed to determine whether there was an increase in the frequency of demodicosis and Demodex density after 20 phototherapy sessions. METHODS: A case-control study was conducted with 32 participants who received narrowband ultraviolet B or ultraviolet A-1 therapy for various dermatological indications. Standardized skin surface biopsies were performed before and after phototherapy to assess Demodex density. The presence of Demodex-related skin conditions was assessed before phototherapy. A statistical analysis was performed to compare the Demodex densities and prevalence of demodicosis between the baseline and 20th session of phototherapy. RESULTS: No significant change was observed in Demodex density after 20 sessions of phototherapy. The average Demodex density before treatment was 2.75 ± 4.48 (/cm2 ), and after treatment, it was 2.85 ± 4.81 (/cm2 ), indicating no significant difference (P = 0.879). The percentage of patients with demodicosis in at least one region of the face was 28.1% (9/32) before treatment, and after treatment, it was 31.3% (10/32), with no significant difference (P = 1.00). CONCLUSIONS: Our findings contradict previous studies that suggested an increased Demodex density and demodicosis prevalence after phototherapy. The data from previous studies are open to debate due to their selected samples, designs, and interpretations regarding the phototherapy-immunosuppression-Demodex relationship. Larger-scale longitudinal studies conducted on a homogeneous sample are warranted to better understand the relationship between phototherapy and demodicosis.

A Delphi approach to establishing consensus on best practice for the diagnosis and treatment of Demodex blepharitis.

Demodex blepharitis does not have agreed standardized guidelines. The aim of this study was to classify signs and symptoms and to develop appropriate management strategies for Demodex blepharitis from a consensus of expert advice. METHODS: A total of 11 anterior segment experts (ophthalmologists, optometrists and a contact lens optician) working in the United Kingdom participated in a modified 2-round Delphi panel. A mixed-methods approach was adopted and a survey questionnaire for round 1 was formulated, constructed from information in the available literature. Based on panel responses from round 1, feedback was provided and a round 2 questionnaire was formulated. More than two-thirds majority (72%) was used for consensus building. RESULTS: Based on the clinical presentation of signs and symptoms along with associated conditions and risk factors, a diagnostic algorithm was proposed for the clinical investigation of Demodex blepharitis. A treatment algorithm was also proposed with first-line and second-line treatment recommendations for Demodex blepharitis. CONCLUSION: The recommendation from this study provides the first effort in formulating clinical diagnostic algorithm and management guidelines for Demodex blepharitis. The guidelines include appropriate magnification on the slit lamp, associated signs, symptoms, risk factors and suggested management options. These guidelines can be used in a routine eyecare setting to encourage eyecare practitioners in tailoring the investigation and management of Demodex blepharitis.

Improved Watershed Algorithm-Based Microscopic Images Combined with Meibomian Gland Microprobe in the Treatment of Demodectic Blepharitis.

The objective of the study was to explore microscopic images under a watershed segmentation algorithm combined with meibomian gland microprobe in the treatment of demodectic blepharitis. For segmenting the connected target objects in the image, the watershed algorithm was utilized first to obtain the target region in the image, and then, the fuzzy C-means (FCM) clustering algorithm was used to cluster the targets. The different grayscale regions in the microscopic images were segmented. 90 patients with demodectic blepharitis-related dry eyes were selected, and they were divided into experimental group 1 (group E1, n = 30), experimental group 2 (group E2, n = 30), and control group (group CG, n = 30). The breakup time (BUT) of the tear film, the subjective score of clinical symptoms, and the number of mites were compared among the three groups before and after treatment. The results showed that after treatment, the indicators of group E1 and group E2 were significantly lower than those before treatment, and the differences were statistically significant (P < 0.05). The treatment effect of group E1 was significantly better than that of the other two groups (P < 0.05). The subjective clinical symptom scores of groups E1, E2, and CG were 13.43 ± 1.41, 13.51 ± 1.41, and 13.64 ± 0.84, respectively, before treatment, and those after treatment were 3.1 ± 1.841, 5.4 ± 0.661, and 13.4 ± 0.841, respectively. The clinical sign scores of the groups E1 and E2 after treatment were remarkably different from those before treatment (P < 0.05). Compared with the scores of clinical signs and clinical symptoms after treatment, those of group E1 showed the largest differences, indicating the best treatment effect. In conclusion, the treatment effect of blepharitis could be promoted with the improved watershed algorithm, and the microscopic images combined with meibomian gland microprobe gave the better effect in the treatment of demodectic blepharitis than the conventional drug heat compress.

Tratamiento de la escabiosis / Treatment of scabies

La escabiosis afecta a más de 200 millones de personas en el mundo, y ocasiona un importante impacto socioeconómico. El mecanismo de contagio es por contacto directo prolongado. El contagio por fómites es infrecuente, aunque puede ser importante en la sarna noruega. La terapia con permetrina tópica al 5% es recomendada como tratamiento de primera línea. Puede indicarse durante el embarazo y la lactancia, y parece ser segura en niños <2 meses. Sin embargo, últimamente se ha reportado una disminución de la efectividad de este fármaco. Otra alternativa en primera línea terapéutica es la ivermectina oral. Se puede administrar durante la lactancia, y estudios recientes sugieren que es segura en niños y lactantes pequeños. Diversas revisiones sistemáticas y metaanálisis han concluido que la ivermectina oral es tan efectiva y segura como la permetrina tópica. La administración terapéutica «en masa» de ivermectina oral es una excelente opción para el manejo de escabiosis en comunidades con alta prevalencia o de brotes en instituciones.

Scabies affects more than 200 million people around the world, and causes a significant socioeconomic impact. Prolonged skin-to-skin contact is the primary mode of transmission. Fomite-mediated transmission is uncommon, although it can be significant in crusted scabies. Topical therapy with permethrin 5% is recommended as first-line treatment. It can be indicated during pregnancy and lactation, and appears to be safe in children <2 months. However, a decrease in the effectiveness of this drug has recently been reported. Another first-line therapeutic alternative is oral ivermectin. It can be administered during lactation, and new evidence suggests that it is safe in children >15kg. Diverse systematic reviews and meta-analysis have concluded that oral ivermectin is as effective and safe as topical permethrin. Mass drug administration of oral ivermectin is an excellent option for the management of scabies in communities with high prevalence, or for scabies outbreaks in institutions.

Population-level impact of native arthropod predators on the poultry red mite Dermanyssus gallinae.

Stimulating the regulation of pests by their natural enemies is a way to improve the sustainability of agriculture and respect for the environment. However, the presence of natural enemies does not guarantee the existence of a pest control service. To what extent are predatory mites commonly found in henhouses actually able to regulate a major egg industry pest mite, Dermanyssus gallinae? To answer this question, we have experimentally recreated portions of a poultry house ecosystem allowing the development of the pest over several generations in the presence of a chick and detritivorous mites (Astigmata) that are ubiquitous and abundant in layer farms. In these conditions, we compared the growth of D. gallinae populations in the presence and absence of native predatory arthropods. No effect of native predators on the growth of the D. gallinae population could be detected despite high initial predator-to-prey ratios and satisfactory growth of predator populations. Prey switching to the alternative prey Astigmata likely dilutes the effect of predation on the target prey. Further exploration is needed to see whether action could be taken to enhance the effect of top-down regulation.

Demodex and eye disease: a review.

Demodex is the most common parasite living on humans and yet little is understood about its pathogenicity with respect to the ocular surface. An increasing interest in Demodex over the past 20-years has increased our understanding of this mite and its pathogenetic role. This article begins with a review of the anatomy, life cycle, mode of transmission and advances in genetics that can distinguish between Demodex folliculorum and Demodex brevis, the only two Demodex species in humans. Additionally, a review of diagnostic procedures and existing and emerging ocular and systemic management options are presented. Despite the increasing interest in Demodex in the literature, there remains numerous obstacles for future studies, hence a section of this review is dedicated to the identification and proposal for future considerations. The lack of uniformity with respect to terminology, diagnostic technique and management approach for Demodex remain as obstacles for future study comparisons. This review summarised the current knowledge on Demodex and hopes to offer some recommendations for future directions in the study of Demodex in humans.

Lactobacillus salivarius A3iob Reduces the Incidence of Varroa destructor and Nosema Spp. in Commercial Apiaries Located in the Northwest of Argentina.

Lactobacillus salivarius A3iob was administered to productive colonies belonging to commercial apiaries of small beekeepers (around 30-50 hives each one), from four departments of the province of Jujuy (Argentina): Yala, Tilquiza, El Carmen, and Los Alisos. The incidence of Varroa destructor and Nosema spp., before and after winter, was monitored during 2 years of study (2014-2015). Depending on the geographical location of each apiary and the application time, a monthly dose of the bacteria (105 CFU/mL) reduced the levels of varroasis between 50 and 80%. Interestingly, L. salivarius A3iob cells remitted the percentage of the mites to undetectable values in an apiary treated with flumethrin (at Yala, Yungas region).On the other hand, the spore levels of Nosema spp. in the lactobacilli-treated colonies also depended on the apiary and the year of application, but a significant decrease was mainly observed in the post-winter period. However, at Rivera (El Carmen's department), no significant changes were detected in both parameters.These results obtained after 2 years of work suggest that delivering L. salivarius A3iob cells to the bee colonies can become a new eco-friendly tool to cooperate with the control of these bees' pests.

The Efficacy of Warm Compresses in the Treatment of Meibomian Gland Dysfunction and Demodex Folliculorum Blepharitis.

Purpose: To investigate and compare the effect of warm compresses on meibomian gland dysfunction and Demodex folliculorum blepharitis.Methods: Forty-two subjects (13 males, 29 females; mean age of 56.45 years) enrolled and completed the two-month warm compress treatment study. Three warm compress therapies were compared: Warm face cloth, MGDRx EyeBag® and OPTASETM Moist Heat Mask. Subjects attended for four visits: baseline, two weeks, four weeks, and eight weeks. Subjective symptoms, osmolarity, non-invasive tear break-up time, ocular surface staining, Schirmer I test, meibum expressibility and clarity, and eyelash manipulation and epilation to assess for the presence of Demodex folliculorum, were measured at each visit.Results: Meibomian gland dysfunction, based on a composite score of meibum quality and expressibility, reduced significantly with the MGDRx EyeBag® and the OPTASETM Moist Heat Mask (p < .05). There was no significant difference in efficacy for treating meibomian gland dysfunction between the two devices (p = .29). No improvement in meibomian gland dysfunction was detected with the warm face cloth. Only the OPTASETM Moist Heat Mask significantly reduced the quantity of Demodex folliculorum over eight-weeks of treatment (p = .036, only baseline to week eight significant p = .008). Symptoms and ocular surface staining improved significantly in all three groups (p < .05). There was no significant change observed in osmolarity, non-invasive tear break-up time or Schirmer I test within each group (p > .05, respectively).Conclusion: The MGDRx EyeBag® and the OPTASETM Moist Heat Mask exhibited superior efficacy in treating signs and symptoms of meibomian gland dysfunction, compared to the use of a warm face cloth, over the eight-week period. The OPTASETM Moist Heat Mask demonstrated dual therapeutic abilities, treating both meibomian gland dysfunction and Demodex folliculorum blepharitis. Repeated application of heat for the treatment of meibomian gland dysfunction may continue to present a good home-remedy option for patients.

The Clinical Use of Eyelash Manipulation in the Diagnosis of Demodex folliculorum Blepharitis.

OBJECTIVES: To compare the efficacy of using an eyelash manipulation technique to the traditional eyelash epilation and subsequent microscopic examination technique, when investigating for the presence of Demodex folliculorum in a clinical setting. METHODS: Four hundred twenty-eight eyelashes of 107 subjects were chosen to compare the quantity of D. folliculorum visible on eyelash manipulation with the slitlamp biomicroscope to that counted on microscopic examination of the same epilated eyelash. One eyelash from each eyelid was rotated with sterile forceps in situ, and the number of D. folliculorum seen emerging from the follicle was counted. The same eyelash was then epilated, and the number of D. folliculorum on the epilated eyelash was counted. Data were analyzed to check for agreement between the two techniques. RESULTS: Intraclass correlation coefficient showed moderately good agreement for assessing the quantity of D. folliculorum (0.78) between the techniques. However, the Bland-Altman plot suggested that consistently higher quantities were found on eyelash manipulation. The overall mean quantity of D. folliculorum was also greater on eyelash manipulation (1.45 mites; range, 0-13 mites) than on microscopic examination of the epilated eyelash (0.81 mites; range, 0-16; P= <0.001). Weighted kappa (κw=0.56) indicated weak levels of agreement between the two methods for addressing severity of infestation. CONCLUSION: Eyelash manipulation exhibited larger quantities of D. folliculorum than complete epilation of the eyelash. In a clinical setting, complete eyelash epilation is not necessary to accurately detect Demodex blepharitis requiring treatment.

Intense Pulsed Light Therapy for Patients with Meibomian Gland Dysfunction and Ocular Demodex Infestation.

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.

A case series of demodicosis in children.

Demodex mites are commensal inhabitants of the pilosebaceous unit that are typically absent or at low numbers in childhood. When they are present, they can cause a primary eruption or exacerbate an underlying facial dermatosis. Here we report five cases of demodicosis occurring in childhood, the clinical presentations, and responses to treatment. Papulopustular lesions predominate, prompting the advice "pustules on noses, think demodicosis!"

Efficacy of treatments for Demodex blepharitis: A systematic review and meta-analysis.

PURPOSE: We conducted a systematic review and meta-analysis to evaluate the efficacy of different treatment for Demodex blepharitis. Parameters studied were mites count, improvement of symptoms and mites' eradication, stratified on type of treatments and mode of delivery of treatments (local or systemic). METHOD: The PubMed, Cochrane Library, Embase, ClinicalTrials.gov, Google scholar and Science Direct databases were searched for studies reporting an efficacy of treatments for Demodex blepharitis. RESULTS: We included 19 studies (14 observational and 5 randomized clinical trials), for a total of 934 patients, 1741 eyes, and 13 different treatments. For mites count, eradication rate, and symptoms improvement, meta-analysis included fifteen, fourteen and thirteen studies, respectively. The overall effect sizes for efficiency of all treatments, globally, were 1.68 (95CI 1.25 to 2.12), 0.45 (0.26-0.64), and 0.76 (0.59-0.90), respectively. Except usual lid hygiene for mites count, Children's Hospital of Eastern Ontario ointment (CHEO) for both eradication rate and symptoms, and CHEO, 2% metronidazole ointment, and systemic metronidazole for eradication rate, all treatments were efficient. Stratified meta-analysis did not show significant differences between local and systemic treatments (1.22, 0.83 to 1.60 vs 2.24, 1.30 to 3.18 for mites count; 0.37, 0.21 to 0.54 vs 0.56, 0.06 to 0.99 for eradication rate; and 0.77, 0.58 to 0.92 vs 0.67, 0.25 to 0.98 for symptoms improvement). CONCLUSION: We reported the efficiency of the different treatments of Demodex blepharitis. Because of less systemic side effects, local treatments seem promising molecules in the treatment of Demodex blepharitis.

A model for the treatment of environmentally transmitted sarcoptic mange in bare-nosed wombats (Vombatus ursinus).

Some of the most important wildlife diseases involve environmental transmission, with disease control attempted via treatments that induce temporary pathogen resistance among hosts. However, theoretical explanations of such circumstances remain few. A mathematical model is proposed and investigated to analyse the dynamics and treatment of environmentally transmitted sarcoptic mange in a population of bare-nosed wombats. The wombat population is structured into four classes representing stages of infection, in a model that consists of five non-linear differential equations including the unattached mite population. It is shown that four different epidemiological outcomes are possible. These are: (1) extinction of wombats (and mites); (2) mite-free wombat populations; (3) endemic wombats and mites coexisting, with the wombats' population reduced below the environmental carrying capacity; and (4) a stable limit cycle (sustained oscillating populations) with wombat population far below carrying capacity. Empirical evidence exists for the first two of these outcomes, with the third highly likely to occur in nature, and the fourth plausible at least until wombat populations succumb to Allee effects. These potential outcomes are examined to inform treatment programs for wombat populations. Through this theoretical exploration of a relatively well understood empirical system, this study supports general learning across environmentally transmitted wildlife pathogens, increasing understanding of how pathogen dynamics may cause crashes in some populations and not others.

Therapeutic Effect of Intense Pulsed Light on Ocular Demodicosis.

PURPOSE: To evaluate the clinical efficacy of Lumenis® M22TM intense pulsed light (IPL) in reduction of ocular Demodex infestation in eyelashes in a prospective study. METHODS: Forty patients with ocular demodicosis were recruited. Then half were randomly picked to receive the IPL treatment, while the other half got 5% tea tree oil (as the control group). Demodex counts, the ocular surface disease index (OSDI) score, lid margin abnormalities, conjunctival congestion, tear break-up time (TBUT), corneal staining with fluorescein, meibomian gland (MG) expressibility, meibum quality, modified Schirmer I test with anaesthetic (SIT), were assessed on the day before treatment and after treatment of 30 and 90 days, respectively. Changes in the parameters were compared between the IPL group and the control group on the days after treatment of 30 and 90 days. RESULTS: No differences were observed in Demodex counts, lid margin abnormalities, conjunctival congestion, corneal staining with fluorescein, MG expressibility, SIT in the two groups on the days after treatment of 30 and 90 days (p > 0.05), whereas there was a statistically significant difference in the OSDI score, TBUT, meibum quality (p < 0.05). The Demodex eradication rate was more thorough in the IPL group (100%) than in the control group (75%). CONCLUSIONS: IPL shows the preferably therapeutic potential for ocular Demodicosis.

Mite and Bed Bug Infections.

Patients with suspected bites or skin rashes regularly present to their primary care physician. Common mite infections encountered in the primary care office include scabies, chiggers, grain itch, and allergic responses from dust mites. In fact, scabies is one of the 50 most prevalent diseases worldwide. Bed bugs are also becoming increasingly common, living in dark crevices, such as mattresses, feeding at night, and causing a maculopapular immune mediated allergic skin response in humans. Proper identification of the mite or bed bug is essential to guide treatment and eradication.

Ocular Demodicosis as a Potential Cause of Ocular Surface Inflammation.

Among different species of mites, Demodex folliculorum and Demodex brevis are the only 2 that affect the human eye. Because demodicosis is highly age-dependent and can be found in asymptomatic adults, the pathogenicity of these mites has long been debated. In this study, we summarize our research experience including our most recent study regarding Demodex infestation as a potential cause of ocular inflammatory diseases. Specifically, we describe the pathogenesis of demodicosis and then discuss the results of work investigating the associations and relationships between ocular demodicosis and blepharitis, meibomian gland diseases, and keratitis, in turn. This is followed by some discussion of the diagnosis of demodicosis and concludes with a brief discussion of evidence for different treatments for ocular demodicosis. Collectively, our studies suggest a strong correlation between ocular demodicosis and ocular surface inflammatory conditions, such as blepharitis, chalazia, meibomian gland dysfunction, and keratitis. Further investigation of the underlying pathogenic mechanism is warranted.