Scabies

Cutaneous Manifestations of Selected Parasitic Infections in Western Pacific and Southeast Asian Regions

Cutaneous manifestations of parasitic infections often result in discomfort, debilitation, and even stigmatization. Data on cutaneous manifestations of parasitic infections, however, are limited. This article provides updates on the cutaneous manifestations of parasitic infections which are known to occur in Western Pacific and Southeast Asian regions, such as scabies, pediculosis, cutaneous larva migrans, larva currens, cutaneous schistosomiasis, cutaneous enterobiasis, cutaneous cysticercosis, acute dermatolymphangioadenitis (lymphatic filariasis), and cutaneous amoebiasis. The lack of epidemiological data on these conditions suggests the need for improvements in recording and reporting of cases. Utilization of advance diagnostic modalities and capacity building of health workers are important for proper case management. Cutaneous manifestations of parasitic infections are a topic rarely studied and thus represent an opportunity for further research.

Working in a danger zone: A qualitative study of Taiwanese nurses' work experiences in a negative pressure isolation ward

BACKGROUND

Hospital nurses are frontline health care workers in controlling the spread of infectious diseases. It is not known if nurses working in negative pressure isolation wards (NPIWs) are better prepared than before to safely care for patients with common infectious diseases.

METHODS

For this qualitative descriptive study, 10 nurses were interviewed in depth about their experiences caring for patients in an NPIW. Tape recordings were transcribed verbatim and analyzed by qualitative content analysis.

RESULTS

The following 5 themes were identified: (1) complexity of patient care, (2) dissatisfaction with the quantity and quality of protective equipment, (3) shortage of nursing staff, (4) continued worries about being infected, and (5) sensitivity to self-protection. Our participants' anxiety and uncertainty about being infected in the NPIW were increased by the complexity of patients' health problems and organizational factors. To protect themselves against infection before and during patient care, participants also developed sensitivity to, concepts about, and strategies to improve self-protection.

CONCLUSIONS

NPIW administrators should pay more attention to nurses' concerns about improving the NPIW working environment, supply good quality protective equipment, and provide appropriate psychologic support and ongoing education to ensure that nurses feel safe while working. This ongoing education should refresh and update nurses' knowledge about disease transmission, therefore decreasing unnecessary anxiety based on misunderstandings about becoming infected.

Chronic pruritus in the elderly: pathophysiology, diagnosis and management

Chronic itch in the elderly is a common problem, with a significant impact on quality of life and sleep in elderly patients. Chronic itch may be attributable to several causes, including dry skin, immunosenescence and neural degeneration. Itch may also be caused by skin diseases, such as seborrhoeic dermatitis and stasis dermatitis; systemic conditions, such as end-stage renal disease and diabetes; and psychogenic conditions, such as depression and anxiety. The use of polypharmacy may also cause itch, with or without a rash. Specifically, thiazides and calcium channel blockers have been known to cause itch in elderly patients. Management should be tailored according to the underlying dermatological or systemic aetiology of itch. Topical treatment is the mainstay of therapy, providing special emphasis on skin hydration and barrier repair. In addition, topical and oral medications that target the nervous system and reduce neuronal hypersensitization, such as gabapentin and selective antidepressants, have a role in treating patients with severe chronic itch. Furthermore, management must account for changes in metabolism and pharmacokinetics of drugs in the aging population in order to prevent the occurrence of adverse effects.

Therapeutic Potential of Tea Tree Oil for Scabies

Globally, scabies affects more than 130 million people at any time. In the developed world, outbreaks in health institutions and vulnerable communities result in a significant economic burden. A review of the literature demonstrates the emergence of resistance toward classical scabicidal treatments and the lack of effectiveness of currently available scabicides in reducing the inflammatory skin reactions and pyodermal progression that occurs in predisposed patient cohorts. Tea tree oil (TTO) has demonstrated promising acaricidal effects against scabies mites in vitro and has also been successfully used as an adjuvant topical medication for the treatment of crusted scabies, including cases that did not respond to standard treatments. Emerging acaricide resistance threatens the future usefulness of currently used gold standard treatments (oral ivermectin and topical permethrin) for scabies. The imminent development of new chemical entities is doubtful. The cumulative acaricidal, antibacterial, antipruritic, anti-inflammatory, and wound healing effects of TTO may have the potential to successfully reduce the burden of scabies infection and the associated bacterial complications. This review summarizes current knowledge on the use of TTO for the treatment of scabies. On the strength of existing data for TTO, larger scale, randomized controlled clinical trials are warranted.

A case of crusted scabies combined with bullous scabies

Scabies is a contagious skin disease that causes extremely itching. It is a parasitic disease caused by the mite Sarcoptes scabiei and characterized by polymorphous lesions. Vesicular and bullous lesions in cases of scabies are rather rare. Bullous scabies has a pemphigoid presentation. Crusted scabies, also known as Norwegian scabies, is a rare and severe form of the disease. The large number of mites present in and on the skin cause scabies to be highly contagious. The present study reports a case of crusted scabies combined with bullous scabies, the clinical and histopathological manifestations of which mimicked those of bullous pemphigoid. Direct and indirect immunofluorescence test results were negative. Bullae recurred and persisted despite systemic corticosteroids and antihistamine medication. The patient was successfully treated with 10% sulfur cream and remained free of recurrence during the 12 months of follow-up. Differential diagnosis with bullous pemphigoid and the mechanism of formation of bullae are also discussed.

Features of human scabies in resource-limited settings: the Cameroon case

Background

The persistent high prevalence of human scabies, especially in low- and middle-income countries prompted us to research the sociodemographic profile of patients suffering from it, and its spreading factors in Cameroon, a resource-poor setting.

Methods

We conducted a cross-sectional survey from October 2011 to September 2012 in three hospitals located in Yaoundé, Cameroon, and enrolled patients diagnosed with human scabies during dermatologists’ consultations who volunteered to take part in the study.

Results

We included 255 patients of whom 158 (62 %) were male. Age ranged from 0 to 80 years old with a median of 18 (Inter quartile range: 3–29) years. One to eight persons of our patients’ entourage exhibited pruritus (mean = 2.1 ± 1.8). The number of persons per bed/room varied from 1 to 5 (mean = 2.1 ± 0.8). The first dermatologist’s consultation occurred 4 to 720 days after the onset of symptoms (mean = 77.1 ± 63.7). The post-scabies pruritus (10.2 % of cases) was unrelated to the complications observed before correct treatment (all p values > 0.05), mainly impetiginization (7.1 %) and eczematization (5.9 %).

Conclusion

Human scabies remains preponderant in our milieu. Populations should be educated on preventive measures in order to avoid this disease, and clinicians’ knowledges must be strengthened for its proper diagnosis and management.

Scabies: an ancient global disease with a need for new therapies

BACKGROUND

Scabies is an ancient disease (documented as far back as 2500 years ago). It affects about 300 million people annually worldwide, and the prevalence is as high as about 60% in Indigenous and Torres Strait Islander children in Australia. This is more than six times the rate seen in the rest of the developed world. Scabies is frequently complicated by bacterial infection leading to the development of skin sores and other more serious consequences such as septicaemia and chronic heart and kidney diseases. This causes a substantial social and economic burden especially in resource poor communities around the world.

DISCUSSION

Very few treatment options are currently available for the management of scabies infection. In this manuscript we briefly discuss the clinical consequences of scabies and the problems found (studies conducted in Australia) with the currently used topical and oral treatments. Current scabies treatment options are fairly ineffective in preventing treatment relapse, inflammatory skin reactions and associated bacterial skin infections. None have ovicidal, antibacterial, anti-inflammatory and/or anti-pruritic properties. Treatments which are currently available for scabies can be problematic with adverse effects and perhaps of greater concern the risk of treatment failure. The development of new chemical entities is doubtful in the near future. Though there may be potential for immunological control, the development of a vaccine or other immunotherapy modalities may be decades away. The emergence of resistance among scabies mites to classical scabicides and ineffectiveness of current treatments (in reducing inflammatory skin reactions and secondary bacterial infections associated with scabies), raise serious concerns regarding current therapy. Treatment adherence difficulties, and safety and efficacy uncertainties in the young and elderly, all signal the need to identify new treatments for scabies.

Interactions among urogenital, intestinal, skin, and oral infections in pregnant and lactating Panamanian Ngäbe women: a neglected public health challenge

Interrelationships among bacteria, protozoa, helminths, and ectoparasites were explored in a cross-sectional survey of 213 pregnant and 99 lactating indigenous women. Prevalences in pregnancy and lactation, respectively, were: vaginitis (89.2%; 46.8%), vaginal trichomoniasis (75.3%; 91.1%), bacterial vaginosis (BV; 60.6%; 63.3%), hookworm (56.6%; 47.8%), asymptomatic bacteriuria/urinary tract infection (AB/UTI; 56.2%; 36.2%), cervicitis (33.3%; 6.3%), vaginal yeast (24.9%; 11.4%), Ascaris (32.5%; 17.4%), vaginal diplococci (20.4%; 31.6%), caries (19.7%; 18.2%), scabies (17.4%; 8.1%), and Trichuris (12.5%; 8.7%). Multiple regressions revealed positive associations during pregnancy (trichomoniasis and AB/UTI; diplococci and Ascaris) and lactation (yeast and scabies). Negative associations were detected in pregnancy (BV and trichomoniasis; hookworm and diplococci) and lactation (BV and yeast). Vaginal Lactobacillus reduced odds of diplococci in pregnancy and lactation, but increased Ascaris eggs per gram (epg) and odds of trichomoniasis in pregnancy and yeast in lactation. These associations raised a concern that treatment of one condition may increase the risk of another.

Enigmatic pruritus in a kidney transplant patient

Pruritus is a common problem following a kidney transplant and is usually attributable to new medications related to transplantation. We present an unusual case of pruritus that began several months after kidney transplantation. After changing several immunosuppressive medications, numerous clinical visits and consideration by the patient of stopping immunosuppression, scabies was diagnosed as the cause. Treatment with oral ivermectin and topical permethrin resulted in complete resolution of symptoms within 1 week. Transplant physicians should consider common causes of pruritus unrelated to transplantation; diagnostic skin lesions of scabies may be absent.

Scabies mites alter the skin microbiome and promote growth of opportunistic pathogens in a porcine model

Background

The resident skin microbiota plays an important role in restricting pathogenic bacteria, thereby protecting the host. Scabies mites (Sarcoptes scabiei) are thought to promote bacterial infections by breaching the skin barrier and excreting molecules that inhibit host innate immune responses. Epidemiological studies in humans confirm increased incidence of impetigo, generally caused by Staphylococcus aureus and Streptococcus pyogenes, secondary to the epidermal infestation with the parasitic mite. It is therefore possible that mite infestation could alter the healthy skin microbiota making way for the opportunistic pathogens. A longitudinal study to test this hypothesis in humans is near impossible due to ethical reasons. In a porcine model we generated scabies infestations closely resembling the disease manifestation in humans and investigated the scabies associated changes in the skin microbiota over the course of a mite infestation.

Methodology/Principal Findings

In a 21 week trial, skin scrapings were collected from pigs infected with S. scabies var. suis and scabies-free control animals. A total of 96 skin scrapings were collected before, during infection and after acaricide treatment, and analyzed by bacterial 16S rDNA tag-encoded FLX-titanium amplicon pyrosequencing. We found significant changes in the epidermal microbiota, in particular a dramatic increase in Staphylococcus correlating with the onset of mite infestation in animals challenged with scabies mites. This increase persisted beyond treatment from mite infection and healing of skin. Furthermore, the staphylococci population shifted from the commensal S. hominis on the healthy skin prior to scabies mite challenge to S. chromogenes, which is increasingly recognized as being pathogenic, coinciding with scabies infection in pigs. In contrast, all animals in the scabies-free cohort remained relatively free of Staphylococcus throughout the trial.

Conclusions/Significance

This is the first experimental in vivo evidence supporting previous assumptions that establishment of pathogens follow scabies infection. Our findings provide an explanation for a biologically important aspect of the disease pathogenesis. The methods developed from this pig trial will serve as a guide to analyze human clinical samples. Studies building on this will offer implications for development of novel intervention strategies against the mites and the secondary infections.

Scabies is a neglected, contagious skin disease caused by a parasitic mite Sarcoptes scabiei. It is highly prevalent world-wide, and now recognized as a possible underlying factor for secondary bacterial infections with potential serious downstream complications. There is currently few experimental data demonstrating directly that mite infestation promotes bacterial infections. Due to remarkable similarities in terms of immunology, physiology and skin anatomy between pigs and humans, we developed a sustainable porcine model enabling in vivo studies of scabies mite infestations. Here, we investigated the impact of the scabies mite infection on the normal pig skin microbiota in the inner ear pinnae in young piglets. Samples obtained prior to, during infection and after acaricide treatment were analyzed by sequencing of bacterial 16S rDNA. We report that scabies infestation has an impact on the host's skin microbiota. Staphylococcus abundance increased with the onset of infection and remained beyond treatment and healing. A shift from commensal to pathogenic Staphylococci was observed. This study supports the link between scabies and Staphylococcus infections, as seen in humans. It is the first in vivo demonstration of a mite induced shift in the skin microbiota, providing a basis for a similar study in humans.

Evaluation of trace elements, oxidant/antioxidant status, vitamin C and β-carotene in dogs with dermatophytosis

The aim of the study was to determine zinc, copper and iron levels, erythrocyte oxidant/antioxidant status, vitamin C and β-carotene in dogs with dermatophytosis. A total of 23 dogs with clinically established diagnosis of dermatophytosis by trichogram and positive fungal culture and six dogs as control were included in this study. On cultural examination 52.17% fungal isolates were found to be Microsporum canis, 30.43% were Trichophyton mentagrophytes and 17.39% were M. gypseum. In comparison to healthy control, the dogs with dermatophytosis had significantly lower levels of zinc (P < 0.01), copper (P < 0.05), β-carotene and vitamin C levels (P < 0.05) and activities of superoxide dismutase (SOD) (P < 0.05) and catalase (P < 0.01), whereas the iron (P < 0.05) and malondialdehyde (MDA) (P < 0.01) levels were significantly increased. On correlation analysis, SOD activity was observed to be positively correlated (P < 0.05) with zinc and copper in both healthy and dermatophytosis affected dogs. In dermatophytosis affected dogs the MDA levels were negatively correlated (P < 0.05) with iron, β-carotene levels and the activities of antioxidant enzymes; SOD and catalase. Our results demonstrated that dermatophytosis in dogs is associated with significant alteration in oxidant/antioxidant balance and trace elements. It might be secondary consequence of dermatophytosis infection or contributing factor in its pathogenesis.

A papulopustular, vesicular, crusted rash in a 4-week-old neonate

Scabies is commonly seen worldwide, in its usual classic form when afflicting older children and adults. However, neonatal scabies is described as its own entity in the literature. We present a case of a 4-week-old infant with a generalized papulopustular, vesicular, and crusted rash who was diagnosed with scabies. We contrast the differing clinical features of neonatal and classic scabies, describe possible mimickers of this diagnostic dilemma, and review current treatment options available for scabies in this very young age group.

Impact of scabies in resource-poor communities

PURPOSE OF REVIEW

Features of endemic scabies are specific in resource-poor and underprivileged communities, with implications for control measures on the community level. In this review, these special aspects are addressed.

RECENT FINDINGS

Scabies is endemic in many resource-poor communities, with a prevalence of 20% and higher. Transmission is influenced by social attitudes, migration, access to healthcare services, housing conditions, hygiene conditions, and crowding. Endemic scabies occurs with severe infestations, complications, and sequels, mainly in children. Sleep loss as a result of scabies-related itching is common. Complications include secondary infections by group A streptococci and acute poststreptococcal glomerulonephritis. Shame, restriction of leisure activities, and stigmatization are common. Treatment of scabies includes a variety of topical compounds, but control on the community level is not an easy task. As ivermectin kills a variety of other parasites, this oral drug is increasingly used for mass treatment. Intervention should address socioemotional aspects using an integrated approach with professionals from different areas, and the community.

SUMMARY

Scabies is a neglected disease and needs to be perceived as an important public health problem causing morbidity in many resource-poor communities. Future work on epidemiology, clinical aspects, transmission dynamics, socioeconomic aspects, and sustainable control in resource-poor communities is needed.

Increased risk of pemphigoid following scabies: a population-based matched-cohort study

BACKGROUND

No prior study has investigated the possibility that scabies patients may be at an increased risk for developing pemphigoid.

OBJECTIVE

To evaluate the risk of pemphigoid following scabies during a 3-year follow-up period using a Taiwanese population-based claims database and taking clinical and demographic characteristics into consideration.

METHODS

This investigation consisted of a study group of 6793 subjects with a diagnosis of scabies and 33 965 randomly selected subjects used as a comparison group. Each patient was tracked for 3 years following their index dates to identify those who received a subsequent diagnosis of pemphigoid. Stratified Cox proportional hazards regressions were used to compute the hazard ratio (HR) of pemphigoid during the 3-year follow-up period.

RESULTS

Of the 40 758 subjects, 52 (0.13%) had received a diagnosis of pemphigoid during the 3-year follow-up period; 33 (0.49% of the study group) were from the study group and 19 (0.06% of the comparison group) were from the comparison group. Compared to subjects without scabies, the HR for pemphigoid for subjects with scabies was 5.93 within the 3-year follow-up period following the index date after adjusting for monthly income, hypertension, diabetes, obesity, psoriasis, stroke, dementia, Parkinson's disease, coronary heart disease, schizophrenia or bipolar disorder, and after censoring those that died during the follow-up period.

CONCLUSIONS

This study detected an increased risk for pemphigoid among patients suffering from scabies. Physicians treating elderly patients with a history of scabies should be alert to the development of pemphigoid.

Scabies increased the risk of chronic kidney disease: a 5-year follow-up study

BACKGROUND

The most documented complication of scabies has been reported to be infection by group A streptococci, which has in turn been suggested to contribute to the development of glomerulonephritis.

OBJECTIVE

This study aimed to investigate the risk of chronic kidney disease (CKD) subsequent to scabies utilizing a population-based dataset in Taiwan.

METHODS

This retrospective matched-cohort study included 5071 subjects with scabies and 25 355 randomly selected comparison subjects. We individually tracked each subject for a 5-year period to identify those who subsequently received a diagnosis of CKD during the follow-up period. Stratified Cox proportional hazards regressions were performed to compute the hazard ratio (HR) of CKD during the 5-year follow-up period.

RESULTS

The incidence rate of CKD during the 5-year follow-up period was 9.66 (8.51-10.93) per 1,000 person-years and 6.24 (5.82-6.69) per 1000 person-years for subjects with and without scabies respectively. The HR for CKD during the 5-year follow-up period for subjects with scabies was 1.34 (95% CI = 1.15-1.56) that of comparison subjects after adjusting for monthly income, hypertension, diabetes, obesity, stroke, coronary heart disease, chronic obstructive pulmonary disease, tobacco use disorder, hyperlipidemia and alcohol abuse during the 5-year follow-up period. Male subjects with scabies were 1.40 (95% CI = 1.14-1.71) times more likely than comparison subjects to suffer from subsequent CKD, and female study subjects were 1.27 (95% CI = 1.05-1.61) times more likely.

CONCLUSIONS

We concluded that there was an increased risk for CKD among patients suffering from scabies.

Comparative trial of permethrin 5% versus lindane 1% for the treatment of scabies

Objective: Treatment of scabies is an important issue in infectious dermatology. The aim of this study was to specify whether permethrin is effective for the treatment of human scabies and to compare its effectiveness with that of 1% lindane by topical application. Methods: 220 patients with scabies with the mean age of 44 ± 12/24 attended the study. Patients were divided into two groups randomly. The first group and their family contacts received 5% permethrin cream and the other received 1% lindane lotion. Treatment was evaluated at intervals of 2 and 4 weeks. Results: Of 254 patients, 220 completed the study. 110 in the group treated with lindane and 110 in the group treated with permethrin. Permethrin provided an improvement rate of 92 (83.6%) after 2 weeks, whereas lindane was effective only in 54 (49%) of patients. After 4 weeks improvement rate was 96.3% (106 of 110) in permethrin group since it was only 69.1% (76 of 110) in lindane group. Conclusion: Permethrin (5%) cream was found to be significantly more effective in the treatment of scabies in comparison with lindane in this study. There were no adverse effects with either permethrin or lindane.

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.

The diagnostic accuracy of dermoscopy for scabies

Background

Scabies is a contagious skin infestation characterized clinically by nocturnal pruritus, visible burrows and contagiousness. Dermoscopy has been suggested as an alternative for diagnosing scabies. But, there have been few well-designed studies evaluating the diagnostic accuracy of dermoscopy.

Objective

We tried to confirm the diagnostic accuracy of dermoscopy for diagnosing scabies. We also tried to demonstrate specific circumstances in which dermoscopic identification of mites ("with dermoscopy") is more useful in diagnosing scabies, and to identify the specific clinical findings that could be used as a possible marker in diagnosing scabies.

Methods

We compared the scraping procedure "with dermoscopy" and "without it" in 49 patients, measuring the duration and outcome of each procedure. Also, we tried to find the specific clinical factors associated with our objects.

Results

The skin scraping "with dermoscopy" was superior to "without it" with respect to the duration and accuracy of the procedure. A history of previous steroid treatment was associated with the superiority of dermoscopy. The correlation between the presence of visible burrows and the positive outcomes of "with dermoscopy" was statistically significant.

Conclusion

Skin scraping with dermoscopy is implicated as the diagnostic method of choice for scabies at the present time. Dermoscopy is especially useful in diagnosis of incognito scabies. In addition, the presence of visible burrows could be a reliable positive marker of scabies in the absence of dermoscopy or microscopy data.

Bullous scabies simulating pemphigoid

BACKGROUND

Scabies is a contagious infestation affecting subjects of all ages, races, and social conditions.

OBJECTIVE

We report a case of a 79-year-old man who developed a bullous pemphigoid-like eruption. He presented to our unit 4 months after the onset of symptoms. An autoimmune bullous disease was suspected. Direct immunofluorescence on a skin specimen and anti-desmoglein 1, anti-desmoglein 3, and anti-bullous pemphigoid antigen 180 were negative. Surprisingly, the histology of a skin lesion demonstrated the presence of scabies, which was successfully treated with benzyl benzoate 20%.

CONCLUSION

The diagnosis of bullous scabies should be considered for any bullous eruptions accompanied by papules and itching resistant to steroid treatment and with negative immunopathologic findings.

An Adolescent Patient with Scabies Mimicking Gottron Papules

Atypical features of scabies occur in infants and children and patients with prolonged use of corticosteroids or immunosuppression. We report a non-immunosuppressed 15-year-old female case of scabies showing scaly reddish papules over the proximal interphalangeal joints mimicking Gottron papules in classic dermatomyositis. Periungal erythema was also seen. Four months' topical corticosteroids from previous clinics had been used. Dermoscopic findings were consistent with typical pictures of scabies. Scraping of hand crusts demonstrated scabies mites and ova. Skin lesions of the patient were cured with oral ivermectin and topical 10% crotamiton. This case suggests that a lesion resembling Gottron papules may be added to the panel of unusual presentations of scabies.