Yoichiro Toi

Changes in Staphylococcus aureus density and lesion severity after topical application of povidone-iodine in cases of atopic dermatitis

A case-control study was performed to examine the efficacy of 10% povidone-iodine solution applied to atopic dermatitis patients. The density of Staphylococcus aureus on the eczematous lesions and the lesion severity before and after the topical application of povidone-iodine were compared. We found a 10-100-fold decrease in the density of S. aureus after povidone-iodine treatment in patients colonizing S. aureus at an initial density of > 1000 CFU/10 cm2. Erythema and exudation also decreased after povidone-iodine treatment in patients colonizing S. aureus at an initial density of > 1000 CFU/10 cm2. The 10% povidone-iodine solution disinfected S. aureus cells when added immediately after the cells were mixed in human plasma; however, 10% povidone-iodine solution only reduced the density of S. aureus cells by 10-100-fold when S. aureus cells were harvested after a 24 h incubation in human plasma. Staphylococcus aureus cells harvested after 24 h incubation in human plasma were often surrounded by fibrin bundles and cells circumscribed by fibrin bundles could not be disinfected with 10% povidone-iodine solution. We suggest that S. aureus cells may produce biofilm-like structures in atopic dermatitis patients and that these structures may help S. aureus cells resist the 10% povidone-iodine treatment.

Antinuclear Antibodies in Patients with Atopic Dermatitis and Severe Facial Lesions

BACKGROUND In adult patients with atopic dermatitis (AD), the presence of autoantibodies such as anti-IgE and antinuclear antibodies (ANA) has been demonstrated. The patients may have altered immune regulation. OBJECTIVE The purpose of this study is to examine the prevalence of ANA in AD patients with severe facial eruptions and to evaluate the differences between ANA-positive and ANA-negative AD patients. METHODS ANA, blood eosinophil count, total serum IgE levels, specific IgE antibody to Dermatophagoides pteronyssinus, disease duration, photosensitivity and association with respiratory allergic diseases were checked in 89 AD patients. RESULTS Twenty-three (25.8%) AD patients showed positive ANA at titers ranging from 1:40 to 1:640, and the incidence of positive ANA was 12.1% in controls. Twenty-five (71.4%) of 35 AD patients with positive ANA at titers ranging from 1:20 to 1:640 were females. CONCLUSION Adult AD patients with severe facial lesions should be examined for serum ANA. Particularly in female and photosensitive AD patients with severe facial lesions, serum autoantibodies have to be carefully investigated to differentiate from autoimmune diseases.

Comparison of the severity of atopic dermatitis lesions and the density of Staphylococcus aureus on the lesions after antistaphylococcal treatment

We examined the relationship between atopic dermatitis (AD) andStaphylococcus aureus by comparing changes in AD lesions and the bacterial density on the lesions after antimicrobial treatment with cefdinir. We found that there was a greater density ofS. aureus on red erythemas and exudative lesions than in light/dark red erythemas and non-exudative lesions of AD. Forty-one of 59 cases (69%) showed a decrease in colony count following antimicrobial treatment. In 28 of 39 cases (72%) there was a decrease of erythema, and in 18 of 22 cases (82%) there was a decrease in the amount of exudate both associated with a decrease in colony density following antimicrobial treatment. Because acute phases of atopic dermatitis, such as red erythemas and exudative lesions, were closely related to the colonization ofS. aureus, dense colonization withS. aureus may be an important factor in the exacerbation of AD. We believe that staphylococcal products such as α-toxin, various enzymes, coagulase, and superantigenic exotoxins affect some aspect of the inflammatory process, resulting in exacerbation of AD.

Linear IgA disease with IgA antibodies directed against 200‐ and 280‐kDa epidermal antigens

We report an 80‐year‐old man with the lamina lucida type of linear IgA disease, with IgA autoantibodies reactive with 200‐kDa and 280‐kDa epidermal proteins. The patient presented with widespread bullous lesions on his trunk and extremities without mucosal involvement. Histopathology of lesional skin showed a subepidermal blister with papillary microabscesses of neutrophils and a few eosinophils. Direct immunofluorescence microscopy of perilesional skin showed linear deposits of IgA and C3 at the basement membrane zone. The patient’s serum contained IgA autoantibodies that bound exclusively to the epidermal side of 1 mol L−1 NaCl split skin as determined by indirect immunofluorescence microscopy. Circulating IgA autoantibodies to 200‐ and 280‐kDa antigens were detected in the patient’s serum by immunoblot analysis using extracts from normal human epidermis and human epidermal keratinocytes. These two antibodies, eluted from individual nitrocellulose membranes, reacted with the epidermal side of 1 mol L−1 NaCl split skin on indirect immunofluorescence microscopy, and bound to hemidesmosomes as determined by immunoperoxidase electron microscopy. This observation suggests the presence of hitherto uncharacterized 200‐ and 280‐kDa hemidesmosomal proteins distinct from BPAG1, BPAG2 and β4 integrin as target antigens in linear IgA disease.

Thyroid gland tumour, pemphigus foliaceus and myasthenia gravis in the daughter of a woman with myasthenia gravis

We describe a rare case of pemphigus foliaceus associated with familial myasthenia gravis (MG). A 35‐year‐old woman developed MG during oral corticosteroid treatment for pemphigus foliaceus. She had been operated on for a thyroid gland tumour that was confirmed histopathologically to be papillary carcinoma without metastasis. At the time of treatment, her mother had had MG for 30 years and undergone thymectomy 22 years ago. A specific ELISA technique showed that antidesmoglein 1 antibody was present in the daughter. There are many reports of multiple diseases such as pemphigus, thymoma, malignancy, and other autoimmune diseases associated with MG. However, familial MG following pemphigus foliaceus has not been reported previously.

Is the face and neck pattern of atopic dermatitis in Japan a special variant

BACKGROUND Adult atopic dermatitis (AD) with severe and refractory eruptions on the face, neck, and upper trunk, although quite rare in western countries, has increased in Japan. OBJECTIVE We have tried to clarify the possible causative factors for this particular type of AD, predominantly seen in Japan. METHODS Eighty-seven AD patients (37 men and 50 women) who had severe and refractory facial and neck lesions were patch tested with topical medicaments, cosmetics, and skin-management products. RESULTS Thirty-seven (42. 5%) patients showed positive reactions to more than one of those products: 14 patients to shampoo, rinse, or soap; 11 to topical nonsteroidal anti-inflammatory agents (NSAIDs); 7 to cosmetics; and 6 to corticosteroids. CONCLUSION We believe that topical NSAIDs, (which are often prescribed for the treatment of AD in Japan and rarely used for the treatment of eczamatous skin disorders in western countries), as well as common detergents, play important roles in the increased prevalence of AD patients with severe and refractory lesions on the face, neck, and upper trunk in Japan.

Giant neuroendocrine (Merkel cell) carcinoma of the skin.

An 82-year-old woman had a dark red to purple tumor on the left buttock that had gradually enlarged during the last 5 years. Although routine histologic examination was not sufficient for diagnosis, neuroendocrine carcinoma was diagnosed by immunohistochemical and ultrastructural studies. Immunohistochemical-positive reactions to neurofilament, cytokeratin, neuron-specific enolase, and epithelial membrane antigen were noted. Electron microscopically, membrane-bound, dense core granules that yielded a positive uranaffin reaction and intermediate filaments in the perinuclear area were observed in the cytoplasm of most tumor cells. Desmosome-like structure between them was also found. Approximately 6 months after local excision, metastatic lesions developed in the regional lymph nodes and liver.