The Prevalence of Incontinence and Its Association With Urinary Tract Infections, Dermatitis, Slips and Falls, and Behavioral Disturbances Among Older Adults in Medicare Fee-for-Service.

PURPOSE: The purpose of this study was to examine the prevalence of urinary (UI), fecal (FI), and dual incontinence (DI) in older adults and their association with urinary tract infections, dermatitis, slips and falls, and behavioral disturbances based on Medicare fee-for-service (FFS) claims data. DESIGN: Retrospective analysis. SUBJECTS AND SETTINGS: Data from administrative claims from the CMS Medicare Limited Data Set (5% sample) for all months in 2018 were reviewed. The analysis was limited to FFS Medicare beneficiaries, with minimum of 3-month enrollment in Parts A and B who were at least 65 years old. This cohort included 1.2 million beneficiaries in the United States. METHODS: We used diagnosis codes to identify members with incontinence and grouped these members into 3 categories (UI only, FI only, and DI). We also divided claims based on 4 sites of care (nursing home, skilled nursing facility, home health, and self- or family care). We then determined the prevalence of (1) urinary tract infections (UTIs), (2) dermatitis, (3) slips and falls, and (4) behavioral disturbances for each type of incontinence. RESULTS: We found that 11.2% of Medicare members had a claims-based diagnosis of incontinence in 2018. On average, those diagnosed with incontinence experienced 5 times more UTIs, 2 times as many dermatitis events, more than twice as many slips and falls, and 2.8 times more behavior disturbances compared to those without an incontinence diagnosis. For those with DI, the prevalence of the 4 outcomes was significantly higher (between 22% and 185%) compared to those with UI only. CONCLUSIONS: Findings show that Medicare beneficiaries diagnosed as incontinent experience a much higher prevalence of UTIs, dermatitis, slips and falls, and behavioral disturbances compared to those without a diagnosis of incontinence. Our results suggest that incontinence may be an important indicator diagnosis for multiple other conditions and, if not well-managed, may challenge the desire for those who are incontinent to age at home.

Human cercarial dermatitis (HCD) in the UK: an overlooked and under-reported nuisance?

BACKGROUND: Human cercarial dermatitis (HCD) is a clinical disease typically caused by skin-penetrative larvae of avian schistosomes. Its geographical epidemiology is firmly tied with that of infected freshwater intermediate snail hosts. To better understand the current distribution of HCD and its level of nuisance in the UK, we undertook a systematic literature review. METHODS: Following PRIMSA guidelines, PubMed and Scopus databases were searched with keywords "human cercarial dermatitis" OR "swimmer's itch" AND "United Kingdom". Articles about imported cases of HCD, or HCD outside the UK, were not formally included. RESULTS: A total of 30 articles were initially identified. A further two were gained by inspection of all citations. After screening, eight publications were analysed where the location, number of cases and putative avian schistosome species incriminated were tabulated. HCD is mainly found in the south of England, though gaps in evidence and reporting remain across the UK. CONCLUSIONS: Despite its noted recent rise in open water swimmers, published literature on HCD across the UK is sparse; this condition is both overlooked and under-reported. We therefore recommend establishing a national database that raises awareness and encourages self-reporting of this nuisance disease.

Pastern dermatitis outbreak associated with toxigenic and non-toxigenic Corynebacterium diphtheriae and non-toxigenic Corynebacterium ulcerans at a horse stable in Finland, 2021.

AIMS: Corynebacterium diphtheriae and Corynebacterium ulcerans, when producing toxin, are the cause of diphtheria, a potentially life-threatening illness in humans. Horses (Equus ferus caballus) are known to be susceptible to infection that may manifest clinically on rare occasions. In late 2021 and early 2022, specimens from five horses suffering from pastern dermatitis were cultured at the Laboratory of Clinical Microbiology at the Faculty of Veterinary Medicine, University of Helsinki, Finland. C. diphtheriae and/or C. ulcerans were recovered from all of these. This study aimed to (1) analyse the bacterial isolates and (2) describe the outbreak and identify possible sources of the infection and infection routes in the stable. METHODS AND RESULTS: Susceptibility testing, PCR for the tox gene, and Elek test for toxin production in PCR-positive isolates were performed. Whole genome sequencing was also conducted to achieve high-resolution strain typing. An epidemiological survey was done by means of a semi-structured interview of horses' caretaker, and contact tracing was done among people at the stable. Two tox gene-positive, toxin-producing C. diphtheriae belonged to sequence type (ST) 822. Other C. diphtheriae (n = 2, ST828) and C. ulcerans (n = 2, ST325 and ST838) isolates did not carry the tox gene. The epidemiological investigation explored numerous possible routes of transmission, but the definite source of infection was not identified. All established human contacts tested negative for diphtheriae. All horses recovered after antimicrobial treatment. CONCLUSIONS: Our study shows that C. diphtheriae and C. ulcerans may readily spread among horses at the same stable and complicate pastern dermatitis infections. These potentially zoonotic bacteria can cause outbreaks even in a country with a very low prevalence. Caretakers should be encouraged to wear gloves and practice good hand hygiene when treating infected skin lesions in horses.

Coronavirus disease 2019 pandemic related chondrodermatitis nodularis helicis: the role of masks.

BACKGROUND: Chondrodermatitis nodularis helicis is a benign, but painful inflammatory condition of the ear, characterised by a tender nodule located on the helix or antihelix. This study aimed to investigate the occurrence of chondrodermatitis nodularis helicis associated with the use of coronavirus disease 2019 masks during the pandemic. METHOD: A retrospective single-centre study was performed from February 2020 to February 2022 in the Maxillo-Facial Unit at the University Hospital of Siena, Italy. RESULTS: During the indexed period, 11 patients were affected by chondrodermatitis nodularis helicis. All patients wore a mask for more than 8 hours a day, every day for several months. CONCLUSION: Although there is no certain proof of the correlation between masks and chondrodermatitis nodularis helicis, an increase in the incidence of this condition was highlighted in our single-centre experience in the pandemic period. The prolonged use of coronavirus disease 2019 masks may explain this correlation.

Equine dermatitis outbreak associated with parapoxvirus.

Parapoxviruses (PPV) cause skin and mucous membrane lesions in several animal species, and of the five recognized PPVs, at least three are zoonotic. Equine PPV (EqPPV) is the sixth one initially described in humans in the United States and later in a severely sick horse in Finland in 2013-2015. In 2021-2022, a large-scale pustulo-vesicular pastern dermatitis outbreak occurred in horses all over Finland. This study aimed at analysing the outbreak, identifying and describing the causative agent, describing clinical signs, and searching for risk factors. EqPPV was identified as a probable causative agent and co-infections with several potentially pathogenic and zoonotic bacteria were observed. Histopathologically, suppurative and ulcerative dermatitis was diagnosed. Due to the lack of specific tests for this virus, we developed a novel diagnostic EqPPV-PCR with sensitivity of 10 copies/reaction. Based on a large proportion of the genome sequenced directly from clinical samples, very little variation was detected between the sequences of the case from 2013 and the cases from 2021 to 2022. Based on an epidemiological survey, the main risk factor for pastern dermatitis was having racehorses. Approximately one third of the horses at each affected stable got clinical dermatitis, manifesting as severe skin lesions. Skin lesions were also occasionally reported in humans, indicating potential zoonotic transmission. Case stables commonly reported attendance at race events before acquiring the disease. Survey also identified differences in practises between case and control stables. Taken together, these results enable a better preparedness, diagnostics, and guidelines for future outbreaks.

An Outbreak of Paederus Dermatitis in a Suburban Hospital in Southwest China: A Report of 134 Cases and Review of Literature.

Reports of paedoptera dermatitis are commonly found in tropical and subtropical regions, while reports in China are rare. In September 2022, an outbreak of paedoptera dermatitis occurred in a minority autonomous county in southwestern China. Here, we report 134 patients with paedoptera dermatitis who were treated at the People's Hospital of Sandu Shui Autonomous County. The skin lesions of these patients were mostly located on the face, neck, trunk, or multiple sites. The skin lesions were mainly distributed in patches and were characterized by vesicular linear or "kissing" lesions. Most patients felt burning pain, and few patients felt pruritus. The treatments with oral antihistamines, calamine lotion, steroids, and antibiotics were effective. For patients with ocular involvement, treatments with oral prednisone and bufexamac cream were effective. All patients recovered within 2 wk. There is a possibility of another outbreak of paedoptera dermatitis in the region. Awareness of the condition and its clinical features will prevent misdiagnosis. Early diagnosis and timely treatment lead to a better prognosis for paederus dermatitis. Simple preventive measures can be undertaken based on the behavioral pattern of this nocturnal beetle.

Outbreaks of dermatopathy caused by Tephrosia noctiflora intoxication in Brazilian cattle.

This study aims to update the knowledge concerning the intoxication by Tephrosia noctiflora in Brazilian cattle herds by reporting new cases of intoxication in lactating cows, their calves and bulls and highlight the epidemiology, clinical signs, pathogenesis, gross, and microscopic lesions. The morbidity and mortality of this intoxication in the farms studied was low. Gross lesions in all affected cattle consisted of dermatitis with hyperpigmentation, crusts, ulceration, erythema, and lichenification in the skin of limbs, ventral abdomen, perianal and perineal areas of lactating calves and adult cattle. Microscopically, the main lesion observed consisted of severe dermatitis with parakeratotic hyperkeratosis, papillated proliferation, and diffuse, accentuated lymphoplasmacytic inflammatory infiltrate in the epidermis and dermis. The presence of skin lesions mainly in the limbs and ventral abdomen of cattle implies the pathogenesis of intoxication is related to a primary contact dermatitis, and the occurrence of similar lesions on the skin of nursing calves reinforces this hypothesis. The putative toxins of T. noctiflora have been thought to be rotenoids. Additional work is needed to define better if these compounds are the main toxin responsible for the dermatopathy observed in these herds.

Epidemiology and healthcare resource utilization in atopic dermatitis in Colombia: A retrospective analysis of data from the National Health Registry from 2015 to 2020 / Epidemiología y uso de recursos de salud en dermatitis atópica en Colombia: análisis retrospectivo de datos del Registro Nacional de Salud de 2015 a 2020

Introduction: Atopic dermatitis, also known as eczema or atopic eczema, is a chronic inflammatory skin disorder characterized by the presence of pruritus accompanied by itching. In Colombia, epidemiological and healthcare resource utilization information regarding this pathology is limited. Objective: To describe atopic dermatitis epidemiological characteristics and healthcare resource utilization patterns in Colombia. Material and methods: A retrospective database study using real-world data obtained from the national claims database SISPRO (Sistema de Información para la Protección Social) for the 2015-2020 period was carried out. Sociodemographic (age, and health services delivery), epidemiological (incidence, prevalence, and comorbidities), and healthcare resource utilization data were extracted from the SISPRO database. Results: The epidemiological results showed increased incidence and prevalence of atopic dermatitis in Colombia in the 2018-2019 period compared to 2015-2017. Accordingly, the number of medical consultations (particularly with specialists), the number of procedures, and the number of hospitalizations of patients with atopic dermatitis increased. Topic and systemic corticoids were the most frequently prescribed drugs. Conclusions: Diagnoses of atopic dermatitis in Colombia increased with a concomitant increase in healthcare resource utilization during 2015-2020, which was possibly slowed down by the arrival of the Covid-19. This study may help physicians gaining a better understanding of the disease, improving atopic dermatitis patient management.

Introducción. La dermatitis atópica, también conocida como eczema o eczema atópico, es un trastorno inflamatorio crónico de la piel caracterizado por la presencia de prurito acompañado de picor. En Colombia, la información epidemiológica y de utilización de recursos sanitarios sobre esta enfermedad es limitada. Objetivo. Describir las características epidemiológicas y los patrones de utilización de recursos sanitarios para la dermatitis atópica en Colombia. Material y métodos. Se trata de un estudio retrospectivo en el cual se utilizan datos de la práctica clínica real obtenidos del registro nacional SISPRO (Sistema de Información para la Protección Social) en el período 2015-2020. Se extrajeron datos sociodemográficos (incluida la edad y la prestación de servicios de salud), epidemiológicos (incluidos la incidencia, la prevalencia y las comorbilidades) y los correspondientes a la utilización de los recursos sanitarios. Resultados. Los resultados epidemiológicos han demostrado un aumento de la incidencia y prevalencia de la dermatitis atópica en Colombia en el periodo 2018-2019, en comparación con el periodo 2015-2017. Aumentó el número de consultas médicas (particularmente, con especialistas) de pacientes con dermatitis atópica, el de procedimientos y el de hospitalizaciones. Los corticoides tópicos y sistémicos fueron los medicamentos más prescritos. Conclusiones. Los diagnósticos de dermatitis atópica en Colombia aumentaron con un incremento concomitante en la utilización de recursos sanitarios durante 2015-2020, que posiblemente se vio atenuado por la llegada del Covid-19. Este estudio puede ayudar a los médicos a tener un mejor conocimiento de la enfermedad y, por lo tanto, mejorar el tratamiento de los pacientes con dermatitis atópica.

An unusual outbreak of dermatitis due to rodent mite infestation in an acute-care hospital.

We report an outbreak of dermatitis associated with Ornithonysus bacoti and Liponyssoides sanguineus infestation in an acute ambulatory care setting. Healthcare workers developed dermatitis prior to the identification of the outbreak. A collaborative team effort resulted in complete eradication.

Incontinence-Associated Dermatitis: Prevalence in Intensive Care Units and Knowledge, Attitudes, and Practices of Nurses.

BACKGROUND: Incontinence-associated dermatitis (IAD) is a major concern among hospitals, especially in intensive care units (ICUs). PURPOSE: To describe ICU nurses' knowledge, attitudes, and practices of IAD and to examine the relationships with IAD prevalence in the ICU setting. METHODS: A descriptive correlational design was used including the Knowledge, Attitudes and Practices of Incontinence-Associated Dermatitis Questionnaire and 1-month IAD prevalence data. RESULTS: The prevalence of IAD in ICUs was 6.89%. A positive correlation was found between IAD prevalence and nurses' IAD knowledge and attitudes. Nurses working in the ICU for more than 7 years, caring for patients at high risk for or having IAD, and thinking IAD-related nursing practices were sufficient had significantly higher IAD knowledge, attitudes, and practices. CONCLUSIONS: Findings indicate that ICU nurses learned about IAD through clinical experience and have inadequate training on IAD. A standardized evidence-based care protocol for IAD should be developed.

Factitious dermatitis in children and adolescents is highly comorbid with psychiatric disorders.

OBJECTIVE: Factitious dermatitis (FD) is a psychocutaneous disorder characterized by self-induced skin lesions. FD is related to mental illness, but the correlation is poorly defined in the pediatric population. Our study aims to investigate the risk of psychiatric disorders diagnosed after the FD diagnosis in children and adolescents. METHODS: We conducted a retrospective cohort study over a seven-year period (2016-2022) to measure the incidence and risk ratio of psychiatric disorders in patients under age 19 years. The FD cohort was defined as patients with FD (International Classification of Diseases, ICD-10-CM: L98.1); the control cohort was defined as patients who attended a regular dermatology visit by applying a diagnostic code of disease of the skin and subcutaneous tissue (ICD-10-CM: L00-99). RESULTS: A total of 453 patients were identified for analysis. We found that FD patients were more likely to be diagnosed with anxiety disorder (Relative risk [RR] 7.63; P < 0.001), obsessive-compulsive disorder (RR 6.20; P < 0.001), attention-deficit hyperactivity disorder (RR 4.90, P < 0.001), depression (RR 2.27; p = 0.02), sleep disorder (RR 2.23; P = 0.01), impulse disorder (RR 2.20; P = 0.04), and conduct disorder (RR 2.14; P = 0.04) within 1 year following the diagnosis of FD. CONCLUSION: FD is highly comorbid with psychiatric disorders. Though some practitioners believe FD could result from experimental or recreational behavior in children and adolescents, possible underlying psychiatric disorders should never be overlooked.

A report of Bilharziella polonica cercariae in Knowsley Safari, Prescot, United Kingdom, with notes on other trematodes implicated in human cercarial dermatitis.

As part of surveillance of snail-borne trematodiasis in Knowsley Safari (KS), Prescot, United Kingdom, a collection was made in July 2021 of various planorbid (n = 173) and lymnaeid (n = 218) snails. These were taken from 15 purposely selected freshwater habitats. In the laboratory emergent trematode cercariae, often from single snails, were identified by morphology with a sub-set, of those most accessible, later characterized by cytochrome oxidase subunit 1 (cox1) DNA barcoding. Two schistosomatid cercariae were of special note in the context of human cercarial dermatitis (HCD), Bilharziella polonica emergent from Planorbarius corneus and Trichobilharzia spp. emergent from Ampullacaena balthica. The former schistosomatid was last reported in the United Kingdom over 50 years ago. From cox1 analyses, the latter likely consisted of two taxa, Trichobilharzia anseri, a first report in the United Kingdom, and a hitherto unnamed genetic lineage having some affiliation with Trichobilharzia longicauda. The chronobiology of emergent cercariae from P. corneus was assessed, with the vertical swimming rate of B. polonica measured. We provide a brief risk appraisal of HCD for public activities typically undertaken within KS educational and recreational programmes.

Spectrum of comorbid autoimmune diseases in patients with chondrodermatitis nodularis helicis: a 17-year retrospective study of 215 patients in Asturias, northern Spain

Background: The cause of chondrodermatitis nodularis helicis (CN) (Winkler's disease) is unknown, but potential associations with autoimmune diseases have been suggested in case reports, however, studies with large case series are lacking. Objectives: To clarify the frequency of chronic inflammatory and autoimmune diseases (CADs), and associated gender and age distribution, in a large cohort of patients with CN. Materials & Methods: The frequency of CADs (systemic and cutaneous) was assessed in 215 patients (65.1% males and 34.9% females; median age: 69.6 years) with a histopathological diagnosis of CN (2000-2017). Endocrine diseases were not included. Statistical analysis included Fisher's exact test and multivariate logistic regression analysis. Results: Twenty different CADs were diagnosed in 15.34% patients with CN. The most frequent were polymyalgia rheumatica (six patients), psoriasis (four patients, one with psoriatic arthritis), rheumatoid arthritis (three patients), CREST syndrome (two patients), vitiligo (two patients), and chronic dermatitis (two patients). Several CADs were strongly associated with tobacco smoking. Systemic CADs were more frequent in females (OR: 3.814; CI 1.513-9.613; p = 0.005; multivariate logistic regression analysis). Differences according to age at onset were not significant. Conclusion: We characterize, for the first time, the spectrum of CADs as well as age and gender distribution in patients with CN based on the largest cohort of patients to date. The possible accumulation of different disorders that are strongly associated with tobacco smoking (Buerger's disease, pulmonary Langerhans cell histiocytosis, rheumatoid arthritis, Lupus erythematosus, and others) merits further investigation, but the rarity of some of them makes this challenging.

Prevalence and clinical relevance of udder thigh dermatitis in dairy cows.

OBJECTIVE: Udder thigh dermatitis (UTD) is especially common in heifers. Skin alterations and necrosis of muscle tissue characterise this condition and, although the disease is well understood, systematic analysis concerning prevalence, risk factors and consequences of UTD is lacking. The aim of this study, therefore were such systematic clinical examinations. MATERIAL AND METHODS: Statistical analyses of data were performed to objectively evaluate the supposed higher risk of heifers developing UTD. The study included a total of 317 animals that were examined and classified as UTD positive or negative on the day of calving. The size of skin alterations and the severity of tissue damage were assessed on days 7, 14 and 21 p. p. RESULTS: The overall prevalence resulted in 18 % UTD with a higher risk in heifers (36.8 %) than in cows (4.3 %; P < 0.0001). A significant link was found between the size of tissue lesions and severity of UTD (day 7: P = 0.007; day 14: P = 0.002; day 21: P = 0.011). Peripartal udder oedemas were strongly associated with UTD (P < 0.05). The milk yield and the concentration of milk protein was found to have decreased. CONCLUSION: UTD appears to be a multi-factorial disease that is supposed to be painful due to the obvious avoidant behaviour in affected animals. In respect to the reduction in daily milk yield and an enhancement of pain related stress, neither the economic impact of UTD, nor the adverse effects on animal welfare should be underestimated. CLINICAL RELEVANCE: Heifers with udder oedema are advised to be examined for the presence of UTD in order to start an early treatment and diminish disease related negative impacts.

Ironing out the wrinkles and folds in the epidemiology of skin fold dermatitis in dog breeds in the UK.

Skin fold dermatitis (intertrigo) is an inflammatory process of closely apposing skin surfaces. Extreme conformations towards folded skin in many dog breeds are linked with higher risk. Using anonymised primary-care veterinary data from the VetCompass Programme, this study aimed to report the frequency, demographic risk factors and clinical management for skin fold dermatitis in the UK. Risk factor analysis used random effects multivariable logistic regression modelling. From a study population of 905,553 dogs, the one-year period prevalence in dogs overall was 0.37% (95% CI 0.35-0.39). Diagnosis was supported by laboratory testing in 4.21% cases. Systemic antibiosis was used in 42.30% cases. Compared with crossbreed dogs, the most highly predisposed breeds were English Bulldog (odds ratio [OR] 49.07, 95% CI 37.79-63.70), French Bulldog (OR 25.92, 95% CI 19.62-34.26,) and Pug (OR 16.27, 95% CI 12.20-21.69). The most protected breeds were Yorkshire Terrier (OR 0.14, 95% CI 0.03-0.56), Border Collie (OR 0.31, 95% CI 0.11-0.84), Jack Russell Terrier (OR 0.53, 95% CI 0.30-0.92) and Labrador Retriever (OR 0.57, 95% CI 0.35-0.93). This study adds further evidence to the welfare concerns around high popularity of dog breeds with extreme conformations. The three breeds with by far the highest odds of skin fold dermatitis represent an extreme brachycephalic conformation.

Dermatitis linearis outbreak associated with Paederus balcanicus in Austria.

BACKGROUND: Dermatitis linearis is a toxic skin lesion caused by contact with certain beetles of the genus Paederus (Coleoptera: Staphylinidae). Dermatitis linearis outbreaks have been described mainly in tropical and subtropical regions, but so far not in Central Europe, and are considered an emerging public health concern potentially associated with climate change. MATERIAL AND METHODS: Following diagnosis of dermatitis linearis in a cluster of six adults and one child with reported exposure to beetles with morphological characteristics of Paederus species at a recreational public open-air bath at Lake Neusiedl (Illmitz, Burgenland, Austria), we performed on-site inspection and installed light and pitfall traps. Collected beetle specimens of the genus Paederus were classified using morphological characteristics and DNA barcoding. RESULTS: A total of 32 Paederus beetles were collected using an aspirator (n = 2) and light traps (n = 30). No individuals of the genus Paederus were captured with the pitfall traps. Morphological analyses identified them as members of the Paederus balcanicus species, which was confirmed by genetic specification of four arbitrarily chosen individuals. Dermatitis linearis lesions were treated with topical steroids and healed but partly leaving scars and hyperpigmentation, over the course of a few weeks in all affected persons. CONCLUSION: We report for the first time (a) an outbreak of dermatitis linearis associated with exposure to autochthonous Paederus species in Austria, and (b) that contact to the species Paederus balcanicus may cause dermatitis linearis in humans. Adequate measures should be taken to prevent dermatitis linearis outbreaks in areas with resident Paederus occurrence.

Shiitake dermatitis: experience of the Poison Control Centre Network in France from 2014 to 2019.

OBJECTIVE: Shiitake mushrooms (Lentinus edodes) are an edible fungus, initially grown in Japan and China that are increasingly marketed in Europe. We previously presented 15 shiitake dermatitis cases reported to Poison Control Centres (PCCs) in France from January 2000 to December 2013. The aim of this study was to describe changes in the number of shiitake dermatitis cases since 2014, and to better describe the clinical characteristics and risk factors of this reaction. CASE SERIES: This observational study is a retrospective review of cases in the French PCCs database between 1 January 2014 and 31 December 2019. Out of 125 shiitake exposures, we identified 59 cases of dermatitis: sex ratio of 1.80 M/F; ages ranging from 19 to 69 years (median: 39 years). Dermatitis occurred after raw or undercooked shiitake consumption (e.g., from the wok, in soup, or on pizza). The rash appeared 1-168 h (median: 48 h) after shiitake ingestion. Linear, erythematous, urticarial papules and plaques developed across the trunk, arms, and legs within a few hours and persisted for 1-40 d (median 10 d). The amount of shiitake eaten (low vs. medium vs. high) significantly increased the duration of dermatitis (median days 4 vs. 7 vs. 15, respectively; p = .007). In all, 38 patients received corticosteroids, antihistamine drugs, or both without demonstrated benefit. All patients made a complete recovery. CONCLUSIONS: The mechanism of shiitake dermatitis is thought to involve lentinan, a heat-labile polysaccharide component. Inadequate cooking clearly seems to be a driver of the occurrence of shiitake dermatitis. This study highlighted a dose-dependent response, suggesting a partial toxic mechanism or a th1-type hypersensitivity mechanism. Treatment is focused on symptom management. Health professionals and the general population should be aware of both the risk associated with inadequately cooked shiitake consumption and the favourable prognosis of this still poorly known toxic dermatitis.