MICROBIOLOGY OF SECONDARILY INFECTED DIAPER DERMATITIS

Specimens obtained from 67 infants with secondarily infected diaper dermatitis were cultured for aerobic and anaerobic bacteria. Bacteria growth was obtained in 58. Aerobic facultative bacteria or Candida sp. only were present in 28 patients (48%), anaerobic bacteria only in 11 (19%), and mixed anaerobic with aerobic, facultative, or yeast flora was present in 19 (33%). Ninety-one bacterial or fungal isolates were recovered (1.6 per specimen), 54 (0.9 per specimen) aerobic or facultative bacteria, 8 (0.1 per specimen) Candida sp., and 31 (0.6 per specimen) strict anaerobes. The predominant aerobic and facultative bacteria were Staphylococcus aureus (23 isolates), Streptococcus sp. (16), and Escherichia coli (6). The predominant anaerobes included Bacteroides sp. (12, including 9 Bacteroides fragilis group) and Peptostreptococcus sp. (11). Single bacterial isolates were recovered in 32 (55%) patients, 18 of which were S. aureus. Twenty-five beta-lactamase-producing bacteria were detected in 22 (51%) of the 43 tested patients. These included 16 S. aureus and 6 B. fragilis group. These data highlight the importance of anaerobic bacteria in the polymicrobial nature of secondarily infected diaper dermatitis.     

Microbiology of infected epidermal cysts

Specimens from 231 epidermal cyst abscesses were inoculated on media supportive for growth of aerobic and anaerobic bacteria. Of these, 192 yielded bacterial growth. Aerobic or facultative bacteria only were recovered in 84 specimens (44%), anaerobic bacteria only in 57 specimens (30%), and mixed aerobic and anaerobic bacteria in 51 specimens (26%). A total of 315 isolates (162 anaerobes and 153 aerobes) were recovered. An average of 0.8 aerobic or facultative isolates per infected cyst were recovered, and this number was unrelated to the cysts' anatomic sites. However, the number of anaerobic bacteria varied; they were isolated more frequently in perirectal (1.5 isolates per specimen), vulvovaginal (1.4), and head (1.1) infections, and less frequently in trunk (0.7) and extremities (0.4) infections. The predominant aerobic or facultative bacteria were Staphylococcus aureus (81 isolates), group A streptococcus (9 isolates), and Escherichia coli (7 isolates). The predominant anaerobic organisms were Peptostreptococcus species (85 isolates) and Bacteroides species (55 isolates, including 12 Bacteroides melaninogenicus and 9 Bacteroides fragilis groups). The study highlights the polymicrobial nature and predominance of anaerobes in cyst abscesses in the perirectal, vulvovaginal, and head areas.     

Microbiology of infected hemangiomas in children

Bacterial infections are a common complication of hemangiomas in children. The objective of this study was to establish the aerobic and anaerobic microbiology of infected hemangiomas. A retrospective 8-year review of clinical and microbiology laboratory records from patients with secondarily infected hemangiomas was carried out. Specimens from infected sites were processed for the presence of aerobic and anaerobic bacteria. Bacterial growth was present in 32 of 38 specimens. Aerobic bacteria alone were recovered in 12 infected hemangiomas (37.5%), anaerobic bacteria alone in 8 (33%), and mixed aerobic and anaerobic flora in 12 (37.5%). A total of 80 isolates (47 aerobes and 33 anaerobes) were recovered, giving an average of 2.5 isolates per specimen (1.5 aerobes and 1.0 anaerobes). The highest number of isolates were recovered in infections of the perineum (3.7 per site) and the legs (2.8 per site). The predominant aerobic isolates were Staphylococcus aureus, group A beta-hemolytic streptococci, and Enterobacteriaceae. The predominant anaerobes were Peptostreptococcus sp., gram-negative bacilli, and Fusobacterium sp. Organisms that belong to the mucous membranes close to the lesions predominated in infections next to those membranes. The polymicrobial etiology of secondarily infected hemangiomas and the association of bacterial flora with the anatomic site of the lesions is thereby demonstrated.     

Aerobic and anaerobic microbiology of chronic venous ulcers

Abstract
Background The role of bacteria in the pathogenesis of chronic venous leg ulcers (CVLU) is unclear. The objective of the study was to establish the aerobic and anaerobic bacteriology of CVLU.
Methods A retrospective review was carried out of the clinical and microbiological laboratory records obtained from patients with CVLU. Microorganisms were grown from 43 specimens obtained from 41 patients.
Results Aerobic or facultative bacteria alone were present in 18 (42%) specimens, anaerobic bacteria only in three (7%), and mixed aerobic–anaerobic flora in 22 (51%).
In total, there were 97 isolates, 64 aerobic or facultative and 33 anaerobic, an average of 2.3 isolates per specimen (1.5 aerobes and 0.8 anaerobes). The predominant aerobic organisms were Staphylococcus aureus (26 isolates), group D streptococci (5), and Escherichia coli (5). The predominant anaerobes were Peptostreptococcus spp. (15), Bacteroides fragilis group (6), Propionibacterium acnes (4), and Prevotella spp. (3).
Conclusions CVLU have a polymicrobial aerobic–anaerobic flora.     

2007年和2008年北京天坛医院痰细菌培养及其药敏结果比较

目的了解北京天坛医院患者痰病原菌分布及其常见病原菌耐药情况。方法2007年和2008年对北京天坛医院急诊及住院患者4225例留取清晨痰标本共3960株进行细菌培养。对病原菌进行细菌学鉴定、药敏试验。对耐甲氧苯青霉素葡萄球菌进行超广谱β内酰胺酶确证试验。结果2007年送检标本中分离到病原菌1706株,其中革兰氏阳性菌687株,占总数的40％,革兰氏阴性菌1019株,占60％。2008年送检标本中分离到病原菌2254株,其中革兰氏阳性菌767株,占总数34％,革兰氏阴性菌1487株,占66％。2007年占前4位的菌株依次为金黄色葡萄球菌、铜绿假单胞菌、鲍曼不动杆菌、大肠埃希氏菌。2008年占前4位的菌株依次为金黄色葡萄球菌、鲍曼不动杆菌、铜绿假单胞菌、大肠埃希氏菌。耐药明显。主要的革兰氏阳性菌（排名前4位）均对万古霉素敏感,对青霉素类均不敏感。结论患者体内分离到的病原菌显著增加,且革兰氏阴性菌所占比例也明显增加。鲍曼不动杆菌由第3位升至第2位,成为占革兰氏阴性菌比例最多的细菌。这些病原菌对青霉素耐药,对万古霉素多敏感。     

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。     

Bacteriological examination of inflamed epidermal cysts: a survey between 2008 and 2009 at a hospital in southern Taiwan

BackgroundInflamed epidermal cysts are common clinical conditions, and they frequently form abscesses. We designed a study to delineate the bacteriology of inflamed epidermal cysts.MethodsWe enrolled 61 adult patients with inflamed epidermal cysts characterized by surface erythema, with or without tenderness, or localized abscess formation within the cyst cavity. Incision and drainage of the cysts were performed, and the contents were sent for aerobic and anaerobic bacterial culture. The locations of the cyst and culture results were recorded for statistical analysis.ResultsA total of 61 cysts and 122 cultures were obtained. The most common locations of the inflamed cysts were the face, neck, and scalp (34.4%), followed by the trunk (32.8%), then the buttocks, inguinal areas, perineum, and axillae (16.4%), and the extremities (16.4%). The culture results were positive in 88.5% of patients, and anaerobes were more frequently isolated than were aerobes. Pure aerobes represented 31.1% of the cultures; pure anaerobes, 36.1%, and combined aerobes and anaerobes, 21.3% (n = 13). The most common anaerobic organisms found were Propionibacterium spp (40.8%), followed by Peptostreptococcus spp (36.7%), Staphylococcus saccharolyticus (14.4%), Prevotella (4.1%), Bacteroides fragilis (2.0%), and Fusobacterium spp (2.0%). The most commonly isolated aerobes were Staphylococcus spp (40%), followed by Enterobacter spp (11.3%), Proteus mirabilis (8.5%), Citrobacter diversus (8.5%), Klebsiella pneumoniae (5.7%), Corynebacterium (5.7%), Morganella morganii (2.9%), Enterococcus faecalis (2.9%), group A β-hemolytic streptococcus (2.9%), Pseudomonas aeruginosa (2.9%), and Providencia rettgeri (2.9%).ConclusionsBoth aerobic and anaerobic microorganisms were present in the inflamed epidermal cysts, although the anaerobic bacteria, specifically, Propionibacterium spp and Peptostreptococcus spp, were isolated slightly more frequently. Antibiotics directed against anaerobes may be considered in the treatment regimen for inflamed epidermal cysts.     

The infectious aetiology of tropical ulcer—a study of the role of anaerobic bacteria

We have cultured anaerobic bacteria from patients with tropical ulcers. Fusobacteria were isolated most frequently. Anaerobes were always present, together with aerobes or facultative anaerobes, particularly in early phase ulcers, suggesting that the combination of organisms is important in the pathogenesis of the disease. Spirochaetes were identified in material examined by light and electron microscopy, but were not cultured.     

Microbiology of infected pustular psoriasis lesions

BACKGROUND: Bacterial infections can occur in lesions of pustular psoriasis (PP). The objective of this study was to establish the aerobic and anaerobic microbiology of secondarily infected PP. METHODS: A retrospective 10-year review was carried out of clinical and microbiology laboratory records from patients with secondarily infected PP lesions, whose specimens of infected sites were processed for the presence of aerobic and anaerobic bacteria. RESULTS: Bacterial growth was noted in 23 specimens. Aerobic or facultative anaerobic bacteria only were present in 12 patients (52%), anaerobic bacteria only in four (17%), and mixed anaerobic-aerobic flora was present in seven (30%). Thirty-six isolates were recovered (1.6 per specimen), 23 aerobic or facultative bacteria and 13 strict anaerobes. The predominant aerobic and facultative bacteria were Staphylococcus aureus (15 isolates), Group D Enterococcus (two isolates), and Escherichia coli (two isolates). The predominant anaerobes were Peptostreptococcus spp. (six isolates) and Bacteroides fragilis group, Propionibacterium acnes, and pigmented Prevotella spp. in two each. Single bacterial isolates were recovered in 14 patients (61%), 11 of which were S. aureus. Nineteen of the organisms isolated from 18 patients (78%) produced the enzyme beta-lactamase. S. aureus was isolated from all body sites. Organisms that resided in the mucous membranes close to the lesions predominated in these infections. Enteric Gram-negative rods and Bacteroides fragilis group predominated in lesions on the legs and buttocks. Group A beta-hemolytic streptococci, pigmented Prevotella, and Fusobacterium spp. were most frequently recovered in lesions of the hand. CONCLUSIONS: The polymicrobial etiology of secondarily infected PP lesions and the association of bacterial flora with the anatomic site of the lesions were demonstrated.     

Anaerobic flora in trophic ulcers in leprosy patients

Material from 108 trophic ulcers from leprosy cases were studied bacteriologically. 4 cases showed growth of pure anaerobes and 69 showed mixed growth of aerobic and anaerobic bacteria. The predominant anaerobes were Fusobacteria (41), anaerobic cocci (30) and Bacteroides (25). Clostridia were isolated only in 10 cases. Metronidazole, chloramphenicol, penicillin and ampicillin were found effective against anaerobes in in-vitro studies.     

重症监护病房革兰氏阴性菌院内感染：217例分析

目的探讨重症监护病房（ICU）革兰氏阴性菌院内感染的临床特点：方法收集温州医学院附属第一医院ICU2005年1月～2007年12月ICU院内感染病例217的痰、尿、血、大便、创口分泌物及腹水标本719份进行细菌培养,并分析革兰氏阴性致病菌的种类和耐药性：结果719份送检标本共分离出各种致病菌658株：革兰氏阴性菌372株,占56．53％。其中占前5位的是鲍曼不动杆菌62株（16．67％）、洋葱假单胞菌61株（16．40％）、铜绿假单胞菌58株（15．59％）、嗜麦芽窄食单胞菌41株（11．02％）、肺炎克莱布斯氏杆菌34株（9．14％）．革兰氏阴性菌院内感染部位主要为下呼吸道（79．84％）、血液（6．99％）和泌尿道（4．84％）：结论ICU院内感染的病原菌多为革兰氏阴性菌,且对绝大多数抗菌药物都耐药。感染部位以下呼吸道占绝大多数。     

Correlation of ultrasonography and bacteriology of the endocervix and posterior cul-de-sac of patients with severe pelvic inflammatory disease

We evaluated 30 patients admitted with a diagnosis of pelvic inflammatory disease (PID) by culdocentesis and ultrasonography to determine the severity of disease in relation to endocervical and culdocentesis bacteriology. Specimens from the endocervix were cultured for Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma hominis, and Ureaplasma urealyticum. In addition, culdocentesis fluid was cultured for aerobes and anaerobes. Patients with N. gonorrhoeae or C. trachomatis had significantly milder disease (P less than 0.05) compared with patients whose specimens were negative for those organisms. Furthermore, those patients with ultrasound confirmation of a tubo-ovarian complex had significantly (P less than 0.0001) greater recovery of aerobes and anaerobes from culdocentesis fluid than did patients with milder disease.     

Microbiology of infected poison ivy dermatitis

We report the aerobic and anaerobic microbiology of secondarily infected poison ivy dermatitis. The study involved retrospective review of clinical and microbiology laboratory records of patients with secondarily infected poison ivy lesions. Bacterial growth was noted in 33 specimens. Aerobic or facultative anaerobic bacteria only were present in 18 (55%) patients, anaerobic bacteria only in seven (21%), and mixed anaerobic-aerobic bacteria in eight (24%). Forty-five isolates were recovered (1.4 per specimen): 27 aerobic or facultative anaerobic bacteria, and 18 strict anaerobes. The predominant aerobic and facultative anaerobic bacteria were Staphylococcus aureus (13 isolates) and group A beta-haemolytic streptococci (six). The predominant anaerobes were Peptostreptococcus spp. (seven isolates), pigmented Prevotella and Porphyromonas spp. (four) and Fusobacterium spp. (two). Single bacterial isolates were recovered in 18 (55%) patients, eight of which were S. aureus. Nineteen of the organisms isolated from 16 (48%) patients produced the enzyme beta-lactamase. Organisms that resided in the mucous membranes close to the lesions predominated in those infections. Enteric gram-negative rods and Bacteroides fragilis group predominated in leg and buttock lesions. Group A beta-haemolytic streptococci, pigmented Prevotella and Porphyromonas and Fusobacterium spp. were most frequently recovered from lesions of the finger, face and neck. The polymicrobial aetiology of secondarily infected poison ivy lesions, and the association of bacterial flora with the anatomical site of the lesions, are demonstrated.     

The anti-microbial activity of maggot secretions: results of a preliminary study

The ability of larval secretions to kill or prevent the growth of a range of potentially pathogenic bacteria was investigated in a preliminary laboratory study. Marked anti-microbial activity was detected against Streptococcus A and B and Staphylococcus aureus. Some activity was also detected against Pseudomonas sp. and a clinical isolate of a resistant strain of S. aureus (MRSA). No evidence of inhibition was recorded against Enterococcus or the Gram-negative bacteria Escherichia coli and Proteus. These findings are consistent with clinical observations made by us and others that larvae of the common greenbottle are able to combat clinical infections in a variety of wound types including those caused by antibiotic-resistant strains of bacteria.     

Anaerobes in genitourinary infections in men.

Urethral and sub-preputial swabs from 150 men were examined. There was a strong association between the isolation of anaerobic bacteria, particularly Bacteroides spp, and a clinical diagnosis of balanoposthitis, non-specific urethritis (NSU), or both. Aerobic bacteria formed the predominant flora in 28 healthy controls whereas anaerobes were predominant in specimens from 79 patients with balanoposthitis, from 24 with NSU, and from 19 with both. Bacteroides spp were the commonest isolates in all patient groups; B asaccharolyticus, B melaninogenicus ss intermedius, B ureolyticus, and B bivius were the most common species. The results obtained with the two swabs were identical except that Gardnerella vaginalis was isolated from the urethral swab only in five patients.     

Anaerobic bacteria and herpes simplex virus in genital ulceration.

Of 91 patients with genital ulceration, herpes simplex virus was isolated from 52 (57%) and Haemophilus ducreyi from 12 (13%); none had syphilis. The difference in incidence of other aerobes in patients and controls was not significant. Anaerobes, predominantly Bacteroides spp, were isolated from a large proportion (77%) of men and women patients with ulcers but from few control men. The most common anaerobic species were B asaccharolyticus and B ureolyticus, with fewer isolates of the melaninogenicus/oralis group. The bacterial flora of herpetic and non-herpetic ulcers were similar, but Candida albicans was isolated significantly more often from non-herpetic ulcers. Anaerobic bacteria may contribute to the pathogenesis of genital ulcers.     

571例皮肤软组织感染住院患者病原菌分布和耐药性分析

目的:研究我院住院患者中皮肤软组织感染者(SSTI)病原菌分布及耐药性。方法:收集571例我院2018年1月1日至2020年12月31日SSTI病原培养结果阳性的住院患者,分析病原菌分布特点以及主要革兰氏阳性优势菌的耐药情况。结果:患者按病种分类,主要有天疱疮、大疱性类天疱疮、湿疹、银屑病等。571例SSTI患者共培养菌株624株,革兰氏阳性菌529株(占84.8%),革兰氏阴性菌76株(占12.1%),真菌19株(占3.0%);主要优势菌为金黄色葡萄球菌、溶血葡萄球菌、中间葡萄球菌,均对青霉素、红霉素、阿奇霉素明显耐药,对米诺环素和替考拉宁敏感性均为100%。结论:金黄色葡萄球菌、溶血葡萄球菌、中间葡萄球菌为我院SSTI最主要致病菌。革兰氏阳性优势菌对青霉素、红霉素、阿奇霉素等耐药率高,对米诺环素、多西环素、替考拉宁、利奈唑胺等耐药率较低,可以指导临床用药。     

Microbiologic evaluation of skin wounds: alarming trend toward antibiotic resistance in an inpatient dermatology service during a 10-year period

BACKGROUND: Increasing resistance to commonly used antibiotics has been seen for patients with superficial skin wounds and leg ulcers. OBJECTIVES: We sought to evaluate bacterial isolates from leg ulcers and superficial wounds for resistance to commonly used antibiotics and to compare current data with previous data. METHODS: We performed a chart review for patients admitted to a tertiary care dermatology inpatient unit from January to December 2001. Comparison was made with 2 previous surveys of the same inpatient service from 1992 and 1996. RESULTS: Bacterial isolates were cultured from 148 patients, 84% (72 of 86) with leg ulcers and 38% (76 of 202) with superficial wounds. Staphylococcus aureus and Pseudomonas aeruginosa were the most common bacterial isolates in both groups. For patients with leg ulcers, S aureus grew in 67% of isolates (48/72) of which 75% (36/48) were methicillin-resistant (MRSA). Of leg ulcers, 35% (25/72) grew P aeruginosa, which was resistant to quinolones in 56% of cultures (14/25). For patients with superficial wounds, S aureus was isolated in 75% (57/76) and 44% were MRSA (25/57). P aeruginosa grew in 17% of isolates (13/76) and was resistant to quinolones in 18%. We found a marked increase in antibiotic resistance for both leg ulcers and superficial wounds. Over time, MRSA increased in leg ulcers from 26% in 1992 to 75% in 2001. For superficial wounds, MRSA increased from 7% in 1992 to 44% in 2001. P aeruginosa resistance to quinolones in leg ulcers increased from 19% in 1992 to 56% in 2001, whereas for superficial wounds there was no resistance in 1992 and 18% resistance in 2001. CONCLUSION: Rapid emergence of antibiotic-resistant bacteria continues and is a problem of increasing significance in dermatology. Common pathogenic bacteria, S aureus and P aeruginosa, showed increased resistance to commonly used antibiotics. Selection of antibiotics should be on the basis of local surveillance programs.     

Skin microflora and bacterial infections of the skin

The skin is a milieu for controlled bacterial growth. Skin supports the growth of commensal bacteria, which protect the host from pathogenic bacteria. Environmental and local factors, host immunity, and organism adherence and virulence are intricately related to cutaneous infection. Resident gram-positive bacteria include Staphylococcus, Micrococcus, and Corynebacterium sp. Staphylococcus aureus and Streptococcus pyogenes are notoriously pathogenic in the skin. In order for bacteria to be pathogenic, they must be able to adhere to, grow on, and invade the host. Bacteria possess numerous virulence genes that allow for growth in these privileged niches. Epidermal infections caused by S. aureus and S. pyogenes include impetigo and ecthyma. Dermal infections consist of erysipelas, cellulitis, and necrotizing fasciitis. The pilosebaceous unit is involved in folliculitis, furunculosis, and carbunculosis. Moreover, S. aureus and S. pyogenes produce toxins that may elicit a superantigen response, causing massive release of cytokines. Staphylococcal scalded skin syndrome, toxic shock syndrome, and scarlet fever are all superantigen-mediated. Gram-negative organisms such as Pseudomonas aeruginosa, Pasteurella multocida, Capnocytophaga canimorsus, Bartonella sp., Klebsiella rhinoscleromatis, and Vibrio vulnificus are not typical resident skin microflora but may cause cutaneous infection.     

Correlations between epithelial cells and bacterial populations in bacteriological skin samples

The purposes of this study were to determine whether the variability in populations of skin bacteria observed between individuals is related to the number of epithelial cells removed during the skin scrubbing procedure and also whether any particular group of microorganisms can be directly associated with epithelial cells. Foreheads of 31 subjects were sampled using the cup scrubbing method, and bacterial populations were quantified as: total anaerobes, aerobes, Propionibacterium spp., aerobic coryneforms, and Micrococcaceae. Epithelial cells were counted in a haemocytometer. Correlation coefficients were positive between total bacterial populations and epithelial cell counts, with the largest values of 0.64 for Propionibacterium spp., 0.58 for Micrococcaceae, and 0.15 for aerobic coryneforms. High epithelial cell counts were always associated with high bacterial populations, but high bacterial counts occurred, in some instances, with low epithehal cell counts; epithelial cells are not, therefore, responsible for variations in bacterial populations in all cases. Stained smears of epithelial cells from subjects from whom aerobic coryneforms were not cultured showed microcolonies of presumptive anaerobic diphtheroids, closely associated with epithelial cells. These findings and the high correlation between Propionibacterium spp. and epithelial cells suggests a re-examination of the location of anaerobes in the stratum corneum.