特应性皮炎皮损金黄色葡萄球菌检出情况的研究

目的 :　探讨特应性皮炎 (AD)皮损微生物定植情况 ,为临床合理选用抗菌药物有效控制该病提供依据。方法 :　无菌生理盐水浸湿的棉拭子于 4 3例AD患者皮损处取标本 ,同时对 39例患者非皮损处及 10例健康人取标本作对照 ,进行细菌培养及菌落计数 ,金葡菌予常规药敏试验。结果 :　AD患者皮损细菌阳性率为 74 .4 2 % ,金葡菌为主要的致病菌 ,占 6 5 .6 3% ;非皮损处也可分离出细菌 ,但金葡菌阳性率及密度均明显低于皮损处 (P <0 .0 0 1)。结论 :　微生物感染因素 ,尤其金葡菌感染或定植 ,在AD的发病中起着重要的作用     

Quantification of anaerobic diphtheroids on the skin.

The widely used technique for sampling skin bacteria employs a detergent (Triton X-100) in buffer solution to remove and suspend the microorganisms. The fraction of the total population of anaerobes on the forehead removed by scrubbing with this solution was estimated. We calculated that approximately 10% of the resident anaerobes were removed by one minute of scrubbing with the detergent solution and two 1-min washes remove approximately 19.5% of the resident anaerobes (8.8 X 10(5)/CM2).     

头面部皮肤鳞状细胞癌组织分离的细菌病原菌构成和耐药性分析

目的 分析头面部皮肤鳞状细胞癌组织分离的细菌病原菌构成及耐药情况。方法 常规方法对246例头面部鳞状细胞癌患者的病变组织或其表面分泌物进行细菌培养,用VITEK TWO全自动微生物分析仪对分离的细菌病原菌进行鉴定,纸片扩散法对分离菌株进行药敏试验。用WHONET 5.3进行统计学分析。结果 共分离菌株294株,革兰阴性菌168株（57.1%）,革兰阳性菌126株（42.9%）。检出率最高的五种病原菌依次为金黄色葡萄球菌（21.4%）、大肠杆菌（20.4%）、表皮葡萄球菌（18.4%）、肺炎克雷伯菌（15.4%）和铜绿假单胞菌（9.5%）。大肠杆菌和肺炎克雷伯菌产超广谱β-内酰胺酶株的检出率分别为40%和26.7%。耐甲氧西林的金黄色葡萄球菌和表皮葡萄球菌的检出率分别为42.9%和55.6%。铜绿假单胞菌、大肠杆菌和肺炎克雷伯菌对亚胺培南和美罗培南高度敏感,对β-内酰胺类和β-内酰胺酶类抑制剂复合物的敏感性较好。未发现耐万古霉素、替考拉宁以及利奈唑胺的葡萄球菌。结论 头面部鳞状细胞癌组织分离的细菌以条件致病菌为主,革兰阴性菌比例略高于革兰阳性菌,对常用的抗生素有较高的耐药性。     

汶川地震致头皮伤口感染细菌谱及耐药性分析

目的探讨地震灾害引起的开放性头皮损伤伤121感染的病原菌分布,耐药性特点及抗生素治疗措施。方法回顾分析5·12汶川地震后,四川大学华西医院神经外科收治的38例开放性颅伤患者头皮伤口感染的病原学资料。结果全组38例开放性头皮伤口感染的病原菌菌株51株,革兰阳性菌35株（68．63％）,分别是金黄色葡萄球菌21株（41．18％）,表皮葡萄球菌14株（27．45％）;革兰阴性菌16株（31．37％）,分别是阴沟肠杆菌8株（15．69％）,肺炎克雷伯杆菌4株（7．84％）,绿脓杆菌2株（3．92％）,深红沙雷氏菌2株（3．92％）。这些菌株对临床常用抗生素都有不同程度的耐药。经彻底清创及应用敏感抗生素,能有效控制感染。结论地震引起的开放性头皮伤口感染的病原菌,多以革兰阳性的金黄色葡萄球菌感染为主。早期彻底清创,营养支持,应用敏感抗生素能提高治疗效果。     

The role of bacteria on facial rosacea-like dermatitis in adult type atopic dermatitis

To investigate the role of bacteria on facial rosacea-like dermatitis lesion in adult type atopic dermatitis, we measured the numbers of bacteria on the skin, nasal and pharyngeal surface of each individual, and then examined its sensitivity to antibiotics. The numbers of bacteria on the surface of skin increased according to the severity of skin eruption. Staphylococcus aureus was detected from the skin and nasal surface more than pharyngeal surface. Bacteria on the pharyngeal surface were both staphylococcus aureus and haemophilus parainfluenzae. Therefore, it is suggested that bacterial flora on the pharynx is different from those of the skin and nose. The treatment with antibiotics was effective for exudative lesions, whereas lichenified lesion did not respond to antibiotic therapy. These results suggest that bacteria on the skin surface are one of precipitating factors of the rosacea-like dermatitis of atopic dermatitis.     

Esterification of (4--14C)cholesterol by cutaneous bacteria (Staphylococcus epidermidis, Propionibacterium acnes, and Propionibacterium granulosum).

Cholesterol and cholesteryl esters constitute 3 to 5% of the lipids derived from human sebaceous glands. The present study demonstrates that cutaneous bacteria, Staphylococcus epidermidis, and to a lesser extent Propionibacterium acnes, and Propionibacterium granulosum, esterify [4--14C]cholesterol to steryl esters in vitro. The degree of esterification is a characteristic of the strain of organism, ranging from 0 to 32.7% in the organisms tested. Cholesterol esterification in these experiments was dependent on the addition of homogenates of isolated, pooled sebaceous glands to the incubation medium. Indirect evidence suggests that the fatty acids from sebaceous triglycerides are utilized for cholesterol esterification by the bacteria. These results indicate that the proportion of steryl esters in skin surface lipids may be influenced by the density of the microbial population in the skin.     

Pleomorphic, variably acid-fast bacteria in an adult patient with disabling pansclerotic morphea

Disabling pansclerotic morphea (DPM) is a rare variant of scleroderma, characterized by immunologic abnormalities and peripheral blood eosinophilia. Sclerodermatous skin specimens from a 24-year-old woman with DPM were studied for the presence of acid-fast bacteria in bacteriologic culture and in microscopic sections. On three of four occasions, a highly pleomorphic organism was cultured from the skin lesions. Detailed bacteriologic investigations indicated that the microbe had unstable and vacillating morphologic characteristics and peculiar acid-fast properties. The organism could be identified as Staphylococcus epidermidis, but it also had stages of growth with morphologic forms more characteristic of a Corynebacterium-like or actinomycetelike microbe. Variably acid-fast coccoid forms, and variably eosinophilic- and basophilic-staining coccoid forms were observed in vivo. The morphologic forms observed in vivo were similar in appearance to some of the growth forms of the microbe observed in vitro, suggesting that such an organism might be implicated to the pathogenesis of DPM.     

In vitro effects of skin lipid extracts on skin bacteria in relation to age and acne changes

Skin lipid extracts of 185 persons of different age were tested in vitro against single representatives of skin bacteria: Staphylococcus aureus, S. epidermidis, Propionibacterium acnes, P. granulosum and Corynebacterium sp. in order to find differences in their inhibitory effects. Percentages of the extracts inhibiting the first 4 bacteria were nearly the same (about 20%) while corynebacteria were inhibited by only 3 extracts. Extracts showing these properties were isolated mainly from adolescents with acne changes, young adults, about 20 yr old, and from children 8--10 yr old, but not from elderly people. The age-related differences in growth inhibition may be related to known differences in relative composition of the sebum constituents according to age. Forty-two extracts of acne patients and healthy adults and adolescents showed an inverse effect in vitro: they enhanced bacterial growth. Growth enhancement was demonstrated only for P. granulosum.     

656例自身免疫性大疱病住院患者皮肤感染的危险因素及病原学分析

目的: 总结自身免疫性大疱病住院患者皮肤感染的相关因素、病原体以及药物敏感特征.方法: 收集2013-2019年自身免疫性大疱病住院患者的临床资料,并对其感染相关因素以及皮肤感染病原体、药物敏感试验进行回顾性分析.结果: 共656例自身免疫性大疱病住院患者纳入分析,皮肤感染率为74.29％,住院时长≥14天与<14天患...     

Hypersensitivity to bacteria in eczema

A study was made of the cytotoxic effect of antibacterial antibody and complement reacting with bacterial antigens firmly adsorbed to epidermal cells. It is believed that this phenomenon enhances the severity of the lesions and their spread in some cases of disseminated eczema. In this first part of the study it is confirmed that Staphylococcus aureus and micrococci are frequently present on lesions and 'unaffected' skin of patients with disseminated eczema. Intradermal skin tests with antigens of staphylococci and micrococci on 122 eczematous patients elicited immediate, or combined immediate and 4 h (Arthus-like) responses, in a large proportion, but few showed uncombined 4 h responses or delayed hypersensitivity, in contrast to findings reported by others. Immunofluorescence tests on skin of thirty patients showed that IgG and IgM diffused into the epidermis, sometimes to the skin surface, of lesional skin, and more immunoglobulin was found in skin of 'unaffected' areas than in skin of normal healthy persons, indicating that clinically unaffected skin in patients with disseminated eczema is abnormal. IgD was present in three of eight samples of unfixed, and six of eight samples of fixed eczematous skin. Staphylococcal and micrococcal antigen was shown on the skin surface and also diffusely in the cytoplasm of cells in the dermis beneath the surface deposits, indicating percutaneous absorption. Further small amounts of antigen were adsorbed to some epidermal cells. These results show that the predisposing conditions for a cytotoxic reaction mediated by hypersensitivity to bacteria do occur. Increased growth of staphylococci and micrococci on eczematous skin would result in increased deposits of antigen. Bacterial antigens are absorbed into the skin and bind with epidermal cells, and immunoglobulins diffuse into the epidermis. Furthermore, skin tests showed that many eczematous patients were hypersensitive to bacteria. Studies on the nature of the antibacterial antibody will be published in the succeeding reports.     

Cutaneous Microflora of Patients with Repeated Skin Infections

The microflora of normal skin in 16 patients with repeated staphylococcal and streptococcal skin infections was examined to determine whether abnormalities existed which would indicate a protective role for the indigenous flora against colonization by pathogens. Five sites-hands, feet, axilla, groin and back-were examined quantitatively and qualitatively and compared with a control group. Total populations of indigenous flora were significantly higher from patients with repeated skin infections of the back, axillae and feet. The frequency of isolation of different species from normal skin was comparable between the control and experimental groups, with the exception of the incidence of Staphylococcus aurcus and Proteus species which were isolated only from patients with repeated skin infections. Gram-negative bacteria were isolated with comparable frequency between the two groups, but patients with repeated skin infections tended to carry gram-negative bacteria on multiple sites. It was concluded from the high population of indigenous flora and the types of microorganisms present that the microflora of normal skin did not appear to protect patients with repeated skin infections against colonization by pathogens. The presence of high populations of Staphylococcus aurcus on the normal skin of patients with repeated skin infections would appear to be the most important contributing factor.     

The combined use of moisturizers and occlusive gloves: an experimental study.

BACKGROUND: Protective gloves are used in the workplace to protect the hands from occupational hazards, but side effects from glove use are frequently reported. Among these side effects, irritant skin reactions are common. OBJECTIVE: The present study was undertaken to investigate whether applying a moisturizer to compromised skin before wearing an occlusive glove could reduce skin irritation. METHODS: Healthy volunteers had both hands immersed in a sodium lauryl sulfate solution twice daily for 2 days. After each immersion, one hand had a moisturizer applied and both hands were put in occlusive gloves for 2 hours. Skin barrier function was evaluated by transepidermal water loss, skin hydration was measured by electrical capacitance and inflammation was evaluated by colorimetry. RESULTS: The moisturizer had a statistically significant positive effect on both the water barrier function and the hydration level of the skin. Although not statistically significant, less inflammation was observed on the moisturizer-treated hand. CONCLUSION: The findings suggest that use of a moisturizer under an occlusive glove may diminish irritation from exposure to a detergent followed by glove wearing.     

Analysis of lipid composition of isolated human sebaceous gland homogenates after incubation with cutaneous bacteria. Thin-layer chromatography.

The effects of specific species of skin bacteria on human sebaceous gland lipids in vitro were analyzed. Isolated dissected sebaceous glands were pooled, homogenized, and sterilized, then incorporated into peptone-yeast extract medium and used as substrate for growth of Propionibacterium acnes, P. granulosum, and Staphylococcus epidermidis subgroup II. The sebaceous lipids were analyzed by thin-layer chromatography before and after bacterial growth. The most striking effect of bacteria on sebaceous gland lipid composition was the hydrolysis of sebaceous triglycerides. The degree of hydrolysis varied with bacterial strain but was most complete with P. acnes and P. granulosum. Staphylococci were not effective in hydrolyzing sebaceous triglycerides at pH 4.5 although, when the pH of the medium was raised to pH 6.4, some strains of staphylococci were as effective as the propionibacteria in hydrolyzing sebaceous triglycerides to free fatty acids. Thus minor changes in acidity may play asignificant role in controlling the lipolytic activity of staphylococci on skin. Another effect of bacterial action on sebaceous gland lipids was the esterification of sebaceous cholesterol to cholesteryl esters. Thus, bacterial action must be taken into account in evaluating studies of alterations in cutaneous cholesterol and cholesteryl esters in skin surface lipids in normal and disease states.     

The in vivo effect of UVB radiation on skin bacteria in patients with atopic dermatitis.

Fourteen patients suffering from atopic dermatitis under treatment with UVB radiation were subjected to aerobic bacterial cultures in order to investigate whether this ultraviolet waveband has any in vivo germicidal effects, and, if so, whether there is a correlation with clinical improvement. Treatments were given 3 times a week for 8 weeks. Bacterial samples were collected before, midway and after the termination of therapy. On the latter two occasions, cultures were performed 30 min and 24 h post-UVB irradiation. The main bacteria found were Staphylococcus epidermidis and S. aureus. S. aureus carriage was found in 12 patients in lesional, dermatitic skin, and in 11 patients in clinically non-lesional skin. UVB radiation was found to have an antimicrobial effect primarily concerning S. aureus. Bacterial counts of this organism in lesional skin were decreased from a mean of 1.3 x 10(3) to 1.2 x 10(1) bacteria per cm2 skin at the 8-week 30-min count (p less than 0.01) and 7.5 x 10(1) at the 8-week 24-h count (p less than 0.05). The treatment yielded a statistically significant clinical improvement.     

Staphylococcal exfoliative toxins: "molecular scissors" of bacteria that attack the cutaneous defense barrier in mammals

Bullous impetigo and its generalized form, staphylococcal scalded-skin syndrome (SSSS), are highly contagious, blistering skin diseases caused by Staphylococcus aureus infection. Virulent strains of the bacteria produce exfoliative toxins (ETs) that cause the loss of keratinocyte cell-cell adhesion in the superficial epidermis. Recent studies have indicated that the three isoforms of ETs, i.e., ETA, ETB, and ETD, are glutamate-specific serine proteases that specifically and efficiently cleave a single peptide bond in the extracellular region of human and mouse desmoglein 1 (Dsg1), a desmosomal intercellular adhesion molecule. In addition, four isoforms of S. hyicus exfoliative toxin, ExhA, ExhB, ExhC, and ExhD, cleave swine Dsg1, resulting in skin exfoliation similar to that observed in pigs with exudative epidermitis. In this review, we describe recent advances in our knowledge of the mechanisms of action of staphylococcal exfoliative toxins, which act as "molecular scissors" to facilitate percutaneous bacterial invasion of mammalian skin by cleavage of keratinocyte cell-cell adhesion molecules. The species-specificity of staphylococcal exfoliative toxins to cleave Dsg1 in certain mammalian species is discussed.     

Semipermeable occlusive dressings. Effects on growth of pathogenic bacteria and reepithelialization of superficial wounds

Six commercially available semiocclusive dressings were tested for their effect on the growth of resident and pathogenic bacteria and the reepithelialization of experimentally induced wounds in human volunteers. Scarification and abrasion-type wounds inoculated with Staphylococcus epidermidis, Staphylococcus aureus, Streptococcus pyogenes, and Pseudomonas aeruginosa were quantitatively cultured at different times after being covered with the dressings. Reepithelialization was assessed by serial stereomicrographs. None of the dressings was able to prevent clinical infection. All dressings provided microenvironments that were conducive to the growth of resident and pathogenic bacteria. There was no difference in the rates of reepithelialization.     

Photodynamic inactivation of multi‐resistant bacteria (PIB) – a new approach to treat superficial infections in the 21st century

The increasing resistance of bacteria against antibiotics is one of the most important clinical challenges of the 21^st century. Within the gram‐positive bacteria the methicillin‐resistant Staphylococcus aureus and Enterococcus faecium represent the major obstacle to successful therapy. Apart from the development of new antibiotics it requires additional differently constituted approaches, like photodynamic inactivation in order to have further effective treatment options against bacteria available. Certain dyes, termed photosensitizers, are able to store the absorbed energy in long‐lived electronic states upon light activation with appropriate wavelengths and thus make these states available for chemical activation of the immediate surroundings. The interaction with molecular oxygen, which leads to different, very reactive and thus cytotoxic oxygen species, is highlighted. In this review the application of the photodynamic inactivation of bacteria will be discussed regarding the possible indications in dermatology, like localized skin and wound infections or the reduction of nosocomial colonization with multi‐resistant bacteria on the skin. The crucial advantage of the local application of photosensitizers followed by irradiation of the area of interest is the fact that independent of the resistance pattern of a bacterium a direct inactivation takes place similarly as with an antiseptic. In this review the physical‐chemical and biological basics of photo‐dynamic inactivation of bacteria (PIB) will be discussed as well as the possible dermatological indications.     

Irritant effects of a detergent in wash and chamber tests

Irritant properties of detergents can be tested by using patch and chamber tests and various kinds of use tests. The aim of the present study was to compare the results of use and 12 mm Finn Chamber® tests. Study subjects (10 atopic and 11 non-atopic medical students) washed the outer aspect of 1 upper arm with liquid detergent for 1 minute 2x daily for 1 week. 48-h chamber test with 5 concentrations of the same detergent in water were concurrently applied to upper back skin. Transepidermal water loss (TEWL), electrical capacitance and skin blood flow were measured to quantify reactions on days 0, 2, 5 and 7. Irritant contact dermatitis developed equally in atopics and non-atopies in the wash test, whereas in the chamber test with a 10% aq. solution of the detergent, increase in TEWL was significantly higher in atopies than in non-atopies. The chamber test results thus predicted poorly the result of the wash test. This might indicate that the wash test and the chamber test measure different aspects of skin barrier function.     

A new in vivo model for the evaluation of topical antiseptics on superficial wounds. The effect of 70% alcohol and povidone-iodine solution

A preliminary evaluation of the antiseptic activity of 70% alcohol and 10% povidone-iodine solution was carried out in an animal model. After the inoculation of partial-thickness wounds with Staphylococcus aureus, 0.1 mL of the antiseptic agent (70% alcohol or povidone-iodine solution) was rubbed into the wound for 30 s. The agent was left on the wound for one minute, three minutes, and 24 hours, and then the wounds were cultured for bacteria. After one minute, the treatments did not reduce the number of pathogens. After three minutes, both 70% alcohol and povidone-iodine solution produced a slight reduction, and after 24 hours, povidone-iodine solution slightly reduced the number of pathogenic bacteria that could be cultured. However, after 24 hours, neither agent reduced the number of pathogens below 10(5) colony-forming units per milliliter. These preliminary data suggest that single applications of 70% alcohol or povidone-iodine may have very limited efficacy as antiseptic agents for the treatment of superficial wounds.     

Quinine sulfate inhibits invasion of some bacterial skin pathogens

BACKGROUND: As some of the many patients who receive antimalarials for the treatment of noninfective inflammatory diseases (lupus erythematosus, collagen vascular diseases, rheumatoid arthritis, and others) are also immunosuppressed because of their disease and/or treatments, and may have concomitant bacterial infections, we investigated the effect of these drugs on the growth and invasion of several bacteria that are commonly associated with skin and soft tissue infections to determine whether they could protect against such conditions and obviate the need for an additional antibiotic drug. METHODS: The effect of quinine sulfate (QS) at concentrations of 50 and 100 microm on the entry process of Enterobacter agglomerans, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae into Caco-2 cells was studied during the infection period. The invasive efficiency was expressed as the number of viable internalized bacteria obtained by counting the colony-forming units (CFUs). RESULTS: The invasive ability of E. agglomerans and S. aureus was significantly inhibited by 50 and 100 microm QS in a dose-dependent manner when the drug was added to Caco-2 cell monolayers during the infection period; however, QS had no significant effect on the internalization of P. aeruginosa or K. pneumoniae. DISCUSSION AND CONCLUSIONS: Antimalarial drugs are currently widely used to treat patients with autoimmune dermatologic and rheumatologic diseases, and have also been recently proposed as additional therapy for patients with human immunodeficiency virus (HIV) infection. These patients, who are often immunocompromised, may receive a secondary advantage from these antimalarials, which may provide some protection against staphylococci (amongst the most important human pathogens causing many superficial and systemic infections) and E. agglomerans.