Investigation of the in-vitro lethal effect of spilanthol on demodex and finding the most effective dose.

Demodex species are associated with many dermatological diseases, so an acaricidal agent that is effective against them and safe for skin applications may benefit many diseases. This study aims to investigate the anti-demodex potential of spilanthol, a product obtained from the Spilanthes Acmella plant, by determining the minimal effective dose for the first time in the literature. Demodex mites were obtained from 70 patients with standard superficial skin biopsy. Spilanthol extract was used at 1%, 2%, 3%, 4%, and 5%. Standard immersion oil was used for the negative control, and permethrin 5% was used for the positive control group. The dependent variable is the survival time of the mite. Comparisons with the negative control group, the anti-demodex effect demonstrated itself in all groups, creating a statistically significant difference (p < 0.001). The positive control group, had 3%, 4%, and 5% spilanthol rates which were very similar to the results with 5% permethrin (p > 0.05). Higher concentrations than 3% did not make any additional contribution to survival times. This is the first attempt to show the dose-dependent acaricidal effect of spilanthol on demodex mites. Even the 3% dose shows similar results to 5% permethrin, and no additional effect increase was observed at higher doses. Therefore, in vivo, studies may be planned with a 3% spilanthol dose for further studies.

The efficacy and safety of permethrin 2.5% with tea tree oil gel on rosacea treatment: A double-blind, controlled clinical trial.

BACKGROUND: Rosacea is a chronic skin condition that typically affects the face and it results in redness and inflammation. The main risk factors of this disease are Demodex folliculorum, living in the pilosebaceous units. AIMS: To evaluate the efficacy and safty of permethrin 2.5% in combination with tea tree oil (TTO) topical gel versus placebo on Demodex density (Dd) and clinical manifestation using standard skin surface biopsy (SSSB) in rosacea patients. PATIENT/METHODS: In this double-blind, randomized clinical trial, 47 papulopustular rosacea patients were enrolled, with 35 patients finishing the 12 weeks of treatment. Each patient used permethrin 2.5% with TTO on one side of the face and a placebo on the other, twice daily for 12 weeks. SSSB, photography and clinical rosacea scores according to National Rosacea Society, as well as adverse drug reaction (ADRs) were reported at the baseline, 2nd, 5th, 8th, and 12th weeks. RESULTS: A total of 47 patients were enrolled with papulopustular rosacea, and 35 patients finished the study. The effects of permethrin 2.5% with TTO gel on mite density were significant at week 5, 8, 12 (P value = .001). Clinical features and global assessments showed papules, pustules and nontransient erythema had improvement in drug group after 12 weeks (P values <.05). The improvement of burning and stinging and dry appearance was greater than the placebo gel (P value <.05). Itching in placebo group was significantly more than other group (P value = .002). CONCLUSION: Administration of permethrin 2.5% with TTO gel demonstrated good efficacy and safety in rosacea. This topical gel inhibited the inflammatory effects of rosacea and reduced Demodex mite.

Severe pediculosis capitis in a nursery school girl / Pediculosis capitis grave en una niña inscrita en una guardería

Pediculosis capitis is the most frequent ectoparasitosis around the world. The infestation is caused by Pediculus humanus capitis (head louse), which affects hair, scalp, and skin. It rarely presents with more symptoms and in the majority of the cases, it shows a benign course if treated properly. We present the case of a nursery school girl with head lice infestation for 18 months. She did not improve after the shampoo treatment. This case was associated with furunculosis, skin lesions, multiple adenopathies, and anemia. Initially, the presence of boils, alopecia, and lymphadenopathy was evident. The persistence of pediculosis capitis and intense scratching induced changes on skin integrity, facilitating opportunistic bacterial superinfection that led to impetiginization, furunculosis, excoriations, hematic scabs, anemia, alopecia, and lymphadenopathies. Pediculosis capitis affected the patient triggering psychological, economic, social, and other health problems. The patient presented uncommon symptoms (furunculosis, anemia, fever, alopecia, and adenopathies) resulting from the persistence of risk factors and the absence of head inspection and mechanical removal of insects. The education about the risk factors, as well as sanitary controls, are essential to contain the infestation.

La pediculosis capitis es la ectoparasitosis más frecuente a nivel mundial. La infestación es causada por Pediculus humanus capitis (piojo de la cabeza) y afecta el cabello, el cuero cabelludo y la piel. Rara vez se manifiesta con otro tipo de sintomatología y, por lo general, su curso es benigno si se trata adecuadamente. Se presenta el caso de una menor con pediculosis capitis de 18 meses de evolución, asociada con forúnculos, lesiones cutáneas, múltiples adenopatías y anemia, que no mejoró tras la aplicación del champú. Inicialmente, llamó la atención la presencia de forúnculos, alopecia y adenopatías. La persistencia de la pediculosis capitis y el rascado intenso alteraron la integridad de la epidermis y facilitaron las infecciones secundarias por bacterias patógenas y oportunistas que produjeron impétigo, forunculosis, excoriaciones, costras hemáticas, anemia, alopecia y linfadenopatías. La pediculosis capitis afectó notoriamente a la paciente al causarle problemas psicológicos y de salud, agudizados por su condición económica y social. La paciente presentó manifestaciones clínicas poco frecuentes (forunculosis, anemia, fiebre, alopecia y adenopatías), lo cual se vio facilitado por la persistencia de los factores de riesgo y el hecho de que no se le inspeccionaba la cabeza ni se removían los insectos. La educación sobre los factores de riesgo y el control sanitario es indispensable para controlar la infestación.

Treatment of Demodex-associated inflammatory skin conditions: A systematic review.

Bacterial folliculitis, rosacea, and other common skin conditions have been linked to infestation by Demodex mites (human demodicosis). Currently, there is little guidance for treatment of inflammatory conditions associated with demodicosis. Thus, the objective of this review is to evaluate the efficacy and safety of treatments utilized for Demodex infestation. PubMed (1946 to January 2019) and Embase (1947 to January 2019) were searched with the following term combinations: Demodex mites, Demodex folliculitis, demodicosis, Demodex folliculorum, or Demodex brevis and articles evaluating treatment of body surface colonization with Demodex mites were included. Common interventions used for Demodex infestation include metronidazole-based therapies, permethrin, benzoyl benzoate, crotamiton, lindane, and sulfur. Short courses of metronidazole taken orally have shown efficacy in reducing Demodex density. Additionally, topical administration of permethrin daily or twice daily was shown to be efficacious across multiple studies. Crotamiton and benzyl benzoate were also efficacious treatments. Several therapies were associated with mild-to-moderate skin irritation. Due to limited data, no standard of care can be identified at this time. Efficacious treatment options may include permethrin, crotamiton, benzyl benzoate, and oral metronidazole; however, long-term efficacy has not been established.

A comparison of the efficacy and tolerability of topical agents used in facial Demodex treatment.

BACKGROUND: Demodex spp. is the most common ectoparasite in humans. This parasite is believed to play a role in the etiology of many dermatological and ocular disorders. AIM: The aim of this study was to compare the efficacy and tolerability of the sulfur-sodium sulfacetamide combination, crotamiton, and permethrin, which are three topical agents commonly used in Demodex treatment. METHODS: A total of 28 patients with primary demodicosis and 44 patients with Rosacea + Demodex were included in the study. The pretreatment and post-treatment Demodex spp. counts, patient satisfaction, and erythema decrease rates were compared. RESULTS: Analysis of the efficacy of these topical agents on Demodex revealed that all three significantly decreased the number of parasites. The patient satisfaction was higher in the sodium acetamide group than the 10% crotamiton and 5% permethrin groups, and clinical evaluation (erythema/ papulopustules and white plugs) was better in the sodium acetamide group than the other groups but no statistically significant difference was found in terms of patient satisfaction and clinical evaluation. CONCLUSION: The sulfur-sodium combination, crotamiton, and permethrin are the three agents commonly used in the treatment of Demodex spp. and all significantly decreased the Demodex count. The three agents were similar in terms of tolerability. Our study needs to be supported with others on larger patient series.

Permethrin enhances the agonist activity of dinotefuran on insect cholinergic synaptic transmission and isolated neurons.

Insect resistance mechanisms against pesticides lead to the development and the search of new pesticide combinations in order to delay the resistance. The combination of neonicotinoids with pyrethroids was currently proposed but the mode of action of these compounds at synaptic and extrasynaptic levels needs to be further explored. In the present study, we evaluated the effect of the combination of two insecticides, permethrin and dinotefuran, on cockroach cholinergic synaptic transmission and on isolated cell bodies. We first found that combination of 5 µM permethrin and dinotefuran enhances depolarization of the sixth abdominal ganglion compared to dinotefuran alone, without an inhibition of the spontaneous activity. However, a pretreatment with 1 µM dinotefuran or permethrin before bath application of the mixture inhibits the ganglionic depolarization. Compared to permethrin, 1 µM dinotefuran induces a persistent enhancement of spontaneous activity. Interestingly, at extrasynaptic level, using dorsal unpaired median neurons and Kenyon cells, we found that combination of both 1 µM dinotefuran and permethrin resulted in an increase of the mixture-induced current amplitudes. Pretreatment with 1 µM dinotefuran strongly decreases the currents whereas permethrin induces a time-dependent inhibition. These data demonstrate that the combination of dinotefuran and permethrin enhances the effect of dinotefuran.

Hidradenitis Suppurativa, Metabolic Syndrome, and Demodex spp. Infestation.

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.

Efficacy of fluralaner (Bravecto™ chewable tablets) for the treatment of naturally acquired Linognathus setosus infestations on dogs.

BACKGROUND: The clinical efficacy of fluralaner chewable tablets (Bravecto™, MSD Animal Health) against naturally acquired Linognathus setosus infestations on dogs was evaluated compared with permethrin (Exspot®, MSD Animal Health) treatment. METHODS: Privately-owned dogs naturally infested with L. setosus from 21 different households were randomly allocated to two treatment groups. Fourteen dogs were treated once orally with fluralaner and ten dogs were treated once topically with permethrin, at the recommended label dose. Live L. setosus on all dogs were counted before treatment and 1, 7, 28 (both groups) and 84 (fluralaner group) days post-treatment according to a coat parting technique at pre-specified locations and lice species were confirmed microscopically. At the same time points, a veterinary dermatology severity score and an owner's perceived pruritus score were recorded. RESULTS: Percentage reduction in geometric mean L. setosus counts, comparing post- with pre-treatment counts within each group, were 85.7% (day 1), 96.8% (day 7) and 100% (days 28 and 84) for the fluralaner (two-sided two-sample t-test, P ≤ 0.0088 for days 1-84) and 67.5% (day 1), 90.3% (day 7) 99.1% (day 28) for the permethrin group (two-sided two-sample t-test, P ≤ 0.0014 for days 7-28). No lice were seen on fluralaner-treated dogs 28 and 84 days post-treatment. In contrast, two permethrin-treated dogs were re-treated at 7 and 28 days after initial treatment because of observed lice. Owner's perceived pruritus scores were reduced compared to pre-treatment levels by 23.8% (day 1), 31.1% (day 7), 70.4% (day 28) and 99.5% (day 84) after fluralaner treatment and 21.3% (day 1), 45.8% (day 7), and 78.1% (day 28) after permethrin treatment. Dermatological signs were improved compared to pre-treatment levels in both treatment groups. CONCLUSIONS: Single oral fluralaner treatment eliminated natural L. setosus infestation on dogs within 28 days and led to complete dermatological recovery that was maintained until the study end on day 84. Single topical permethrin treatment reduced the number of L. setosus by 99.1% at day 28 although two animals required unscheduled re-treatment.

Efficacy and safety of permethrin 5% topical gel vs. placebo for rosacea: a double-blind randomized controlled clinical trial.

BACKGROUND: Rosacea is a chronic, multifactorial, dermatological condition. Increased density of Demodex folliculorum mites in the skin of rosacea patients suggests a possible role for these mites in the pathophysiology of rosacea. OBJECTIVE: To evaluate the effects of permethrin 5% topical gel vs. placebo on Demodex density (Dd) and clinical presentations of rosacea patients, and also to further refine the quantitative assessment of Dd in the non-invasive standard skin surface biopsy (SSSB). METHODS: Twenty patients with bilateral papulopustular rosacea and ≥5 mites/cm2 were enrolled in the study. Participants and physicians were blinded to the group assignments. Each patient applied permethrin on one side and placebo on the other side of the face twice daily for 12 weeks. SSSB and photography and Rosacea Clinical Scorecard of the National Rosacea Society were used to assess the patients at the baseline, 2nd, 5th, 8th, and 12th weeks for both sides of the face. Causality and severity of adverse drug reactions (ADRs) were assessed by WHO Scale and Hartwig Scale, respectively. RESULTS: Dd was not significantly different between the two groups at the baseline. In both groups, Dd significantly decreased after 12 weeks compared to the baseline. At the end of the 12th week, the Dd in the permethrin group was significantly lower than the placebo group. Severity of the clinical presentations decreased in both groups at the end of week 12 in comparison to the baseline, particularly in the permethrin group. ADRs were all mild and in most cases unlikely related to permethrin. CONCLUSION: Permethrin 5% gel can significantly reduce the Dd and severity of presentations in rosacea patients and can be a safe and effective option in the management of this chronic disorder. This new SSSB technique offers an easy, quick, inexpensive, and non-invasive sampling method proper for quantitative assessment of Dd.

Knock-down and speed of kill of a combination of fipronil and permethrin for the prevention of Ctenocephalides felis flea infestation in dogs.

BACKGROUND: A topical combination of fipronil + permethrin (Frontline Tri-Act/Frontect, Merial) has recently been developed to control fleas, ticks, mosquitoes, sandflies and stable flies on dogs. Two studies were conducted to assess its speed of kill and knock-down effect on Ctenocephalides felis fleas. The combination was compared to either fipronil alone or to a combination of permethrin, dinotefuran, and pyriproxyfen, METHODS: In each study, 18 dogs were randomly allocated to one of three groups: (Group 1: untreated dog; Group 2: treated once on D0 with the combination of fipronil and permethrin; Group 3: treated once on D0 either with fipronil alone (study 1) or with a combination of permethrin, dinetofuran and pyriproxyfen (study 2)). Each dog was infested with 100 unfed adult C. felis fleas on Days 2 (study 2), 7, 14, 21 and 28. Fleas were collected from dogs at 1 h and 12 h post- infestations (PI) (study 1) or at 2 h and 6 h PI (study 2) to assess efficacy and from collection pans underneath cages 1 h (study 1) or 5 min (study 2) PI to assess knock-down effect. RESULTS: All treated dogs had significantly (p ≤ 0.01) lower flea counts than untreated dogs at every time point in both studies. For a whole month, a significant knock-down effect against infesting fleas is obtained in five minutes PI with the combination of permethrin and fipronil. Complete efficacy (>95%) was achieved in 1 h (study 1) or 2 h (study 2) PI for 14 days and by 6 h PI for all challenges conducted throughout the month. Efficacy remains >85% at 2 h PI for the whole month. A significantly higher efficacy of the fipronil + permethrin combination compared to other treatments was demonstrated at the earliest time points for the month (1 h knock-down effect and insecticidal efficacy compared to fipronil alone; 5 min knock-down effect compared to the combination of permethrin + dinetofuran + pyriproxyfen). CONCLUSIONS: The rapid flea knock-down effect and speed of kill demonstrated by the spot on combination of fipronil + permethrin provide a reliable strategy against flea infestations in dogs.

Serie parasitosis en dermatología: pediculosis / Parasitosis in dermatology: pediculosis

La enfermedad producida por Pediculus humanus capitis, conocida como pediculosis, es una parasitosis específica del ser humano de distribución mundial. El contagio puede ser directo por contacto con el cuero cabelludo de una persona afectada, o por fómites contaminados con parásitos, por lo que no distingue raza, sexo, edad ni nivel socioeconómico. Presentamos el caso de una paciente de 80 años con una forma típica de pediculosis. (AU)

The disease caused by Pediculus humanus capitis, known as pediculosis, is a human specific parasitosis. It has a worldwide distribution. Transmission can be by direct contact with the scalp of an affected person or by contaminated fomites with parasites. This infestation makes no distinction of race, sex, age, or socioeconomic status. We present a case of an 80 years old patient with a typical case of pediculosis. (AU)

Scabies.

Scabies infestation in humans is a complex interplay between mite, host, and host environment. New techniques for diagnosis, treatment, and eradication are constantly in flux due to varying presentations of scabetic eruptions, a dearth of especially sensitive and specific measures for diagnosis, resistances to pharmacologic therapy, and disparate regional resources. This review will provide an update on the clinical variations, detection methods, and management options.

The efficacy of a combined larvicide-adulticide in ultralow volume and fumigant canister formulations in controlling the dengue vector Aedes aegypti (Diptera: Culicidae) in Northwest of Argentina.

The efficacy of an ultralow volume formulation (ULV) and fumigant canister, containing both permethrin and pyriproxyfen, was compared with that of standard permethrin applications in a field assay conducted in Banda del Río Salí, Tucumán (north-western Argentina). Five treatment areas were established: first area was sprayed with a ULV formulation of 10 % permethrin, a second area was treated using a fumigant canister containing 10 % permethrin and 3 % pyriproxyfen, the third area was sprayed with a ULV formulation of 10 % permethrin and 3 % pyriproxyfen, the fourth area with ULV formulation of 10 % permethrin using a portable aerosol generator and the fifth area was a left untreated area. Immature and adult Aedes aegypti individuals placed in containers and sentinel cages were positioned within the treated and control areas. The effects of treatment and time on larval, pupal and adult survival were tested. We also investigated the effects of treatment and time on the numbers of larval and pupal deaths, on the proportion of larvae that metamorphosed into pupae and adults, and on the proportion of dead adults. Larval A. aegypti survivorship in 250 mL containers revealed a significant treatment effect and significant treatment × time interaction 2 and 24 h after the application of the ULV treatment with 10 % permethrin using the portable aerosol generator. The number of dead larvae in 20 L containers differed significantly by treatment and by time. ULV treatment with 10 % permethrin and 10 % permethrin plus 3 % pyriproxyfen using the cold fogger truck mount ULV resulted in the greatest numbers of dead larvae; most larvae died 2 weeks after application. Adult A. aegypti mortality in all treatments did not differ significantly 2 and 24 h after application. In addition, we found no significant differences in adult mortality between cages exposed at 3 m and those at 6 m from the ULV application line. However, there was a significant difference in adult mortality between the 10 % permethrin treatment applied with cold fogger truck mount ULV and that applied using the portable aerosol generator (P < 0.001). The larval index known as Breteau index (BI) was higher before treatment than after treatment in different areas. After the treatments, the lowest value of BI was observed in the area treated with the fumigant canister formulation, and a long-lasting effect was observed with the formulation of 10 % permethrin and 3 % pyriproxyfen.

Pesticide and insect repellent mixture (permethrin and DEET) induces epigenetic transgenerational inheritance of disease and sperm epimutations.

Environmental compounds are known to promote epigenetic transgenerational inheritance of disease. The current study was designed to determine if a "pesticide mixture" (pesticide permethrin and insect repellent N,N-diethyl-meta-toluamide, DEET) promotes epigenetic transgenerational inheritance of disease and associated DNA methylation epimutations in sperm. Gestating F0 generation female rats were exposed during fetal gonadal sex determination and the incidence of disease evaluated in F1 and F3 generations. There were significant increases in the incidence of total diseases in animals from pesticide lineage F1 and F3 generation animals. Pubertal abnormalities, testis disease, and ovarian disease (primordial follicle loss and polycystic ovarian disease) were increased in F3 generation animals. Analysis of the pesticide lineage F3 generation sperm epigenome identified 363 differential DNA methylation regions (DMR) termed epimutations. Observations demonstrate that a pesticide mixture (permethrin and DEET) can promote epigenetic transgenerational inheritance of adult onset disease and potential sperm epigenetic biomarkers for ancestral environmental exposures.

Rapid control of a scabies outbreak at a tertiary care hospital without ward closure.

BACKGROUND: Although scabies outbreaks in hospitals are frequent, the optimal approach to management of these outbreaks has not yet been defined. We describe a hospital scabies outbreak that was successfully controlled without ward closure. METHODS: An outbreak of scabies at a teaching hospital and subsequent control measures were investigated. Outcomes included the number of cases affecting patients and staff, number of patients and staff requiring prophylaxis, duration of the outbreak, and cost of the outbreak. Outcomes were compared with those in a similar outbreak occurring at the same hospital 20 years earlier and with other published descriptions of hospital scabies outbreaks. RESULTS: In January 2010, a patient who had undergone renal transplantation was admitted 3 times to St. Michael's Hospital, but a diagnosis of scabies was not considered until the final admission. Widespread exposure of patients and staff on 2 wards prompted the establishment of an outbreak management team. Initial interventions focused on isolation and treatment of the index case and on contact tracing to identify and treat secondary cases and to offer prophylaxis to direct contacts. Five symptomatic staff members and 2 patient cases were quickly identified, an outbreak was declared, and mass simultaneous prophylaxis was initiated on the 2 involved wards. A single case occurred 2 weeks after the mass prophylaxis program in a staff member who had not received the prophylaxis. Six weeks after the onset of symptoms, the end of the outbreak was declared. No additional cases have been reported up to the time of publication. The total cost of the outbreak was $20,000. CONCLUSIONS: Early recognition of crusted scabies is essential to prevent outbreaks. Once an outbreak occurs, prompt control of the index patient and rapid tracing of contacts to identify secondary cases are necessary. When prolonged exposure to a case of crusted scabies results in multiple secondary cases, institution of simultaneous mass prophylaxis is the most efficient strategy for terminating the outbreak and can be implemented without ward closure.

[Hyperkeratotic plaques and generalized pruritus in a 47 year-old man]. / Borkenkrusten und generalisierter Juckreiz bei einem 47-jährigen Mann.

A 47-year-old man presented with generalized pruritic lesions that had persisted for 2 years and shown no response to therapy with topical corticosteroids. The identification of numerous mites in the patient's scales led to the diagnosis of crusted scabies. The lesions responded to systemic therapy with Ivermectin (Stromectol) and topical application of Permethrin (InfectoScab). As underlying factors we suspect the immunosuppressive therapy attempts with topical corticosteroids as well as alcohol abuse.

Scabies presenting as solitary mastocytoma-like eruption in an infant.

We report a case in which the initial clinical finding was a solitary cutaneous nodule on the wrist of a young infant which urticated when rubbed, and was diagnosed as a solitary mastocytoma. Two months later, she had the onset of a new vesiculo-pustular eruption on the palms and soles, consistent with scabies infestation and treatment with topical permethrin 5% cream resulted in resolution of the entire eruption, including the primary nodule. While scabies has been reported to mimick a variety of conditions including urticaria pigmentosa, to our knowledge no previous cases masquerading as solitary mastocytoma have been reported.