Effectiveness of gentian violet and similar products commonly used to treat pyodermas.

The term pyoderma encompasses a variety of distinct entities including impetigo (bullous and nonbullous), erysipelas, cellulitis, folliculitis, and staphylococcal scalded skin syndrome. Treatment of pyodermas centers around wound care and appropriate antibiotic selection. Triphenylmethane dyes, such as gentian violet, represent a unique group of compounds that act as antiseptics and have shown clinical efficacy as antibiotics in a variety of pyodermas, including those secondary to methicillin-resistant Staphylococcus aureus. Given their low cost, ease of application, and favorable side effect profile, triphenylmethanes must be considered legitimate treatment options for pyodermas, particularly in the face of continued and emerging bacterial resistance.

Group A streptococcal infections in children.

The group A streptococcus causes the widest range of disease in humans of all bacterial pathogens. Group A streptococcal diseases are more common in children than adults with diseases ranging from pharyngitis and impetigo to invasive infections and the post-streptococcal sequelae--acute rheumatic fever and acute post-streptococcal glomerulonephritis. The global burden of severe group A streptococcal disease is concentrated largely in developing countries and Indigenous populations such as Aboriginal Australians. Control of group A streptococcal disease is poor in these settings and the need for a vaccine has been argued. With an ever-increasing understanding of the group A streptococcus at a molecular level, new and sophisticated vaccines are currently in human trials and the next decade holds exciting prospects for curbing group A streptococcal diseases.

Acute rheumatic fever: a chink in the chain that links the heart to the throat?

Acute rheumatic fever (ARF) remains a major problem in tropical regions, resource-poor countries, and minority indigenous communities. It has long been thought that group A streptococcal (GAS) pharyngitis alone was responsible for acute rheumatic fever; this belief has been supported by laboratory and epidemiological evidence gathered over more than 60 years, mainly in temperate climates where GAS skin infection is uncommon. GAS strains have been characterised as either rheumatogenic or nephritogenic based on phenotypic and genotypic properties. Primary prevention strategies and vaccine development have long been based on these concepts. The epidemiology of ARF in Aboriginal communities of central and northern Australia challenges this view with reported rates of ARF and rheumatic heart disease (RHD) that are among the highest in the world. GAS throat colonisation is uncommon, however, and symptomatic GAS pharyngitis is rare; pyoderma is the major manifestation of GAS infection. Typical rheumatogenic strains do not occur. Moreover, group C and G streptococci have been shown to exchange key virulence determinants with GAS and are more commonly isolated from the throats of Aboriginal children. We suggest that GAS pyoderma and/or non-GAS infections are driving forces behind ARF in these communities and other high-incidence settings. The question needs to be resolved as a matter of urgency because current approaches to controlling ARF/RHD in Aboriginal communities have clearly been ineffective. New understanding of the pathogenesis of ARF would have an immediate effect on primary prevention strategies and vaccine development.

Macroscopic, cytological and bacteriological evaluation of anal sac content in normal dogs and in dogs with selected dermatological diseases.

Macroscopic and cytological aspects of anal sac content were evaluated in 40 normal dogs and 10 dogs each with pyoderma, Malassezia dermatitis associated with atopic dermatitis and uncomplicated atopic dermatitis. Bacteria isolated from anal sacs were compared with those from abdominal skin and hair in 20 normal dogs and 10 dogs with pyoderma. There was no difference between the groups in anal sac dimension, or in the colour, consistency or presence of granules in their content. Extracellular bacteria were found in higher numbers in diseased animals, whereas intracellular bacteria were observed in 40% of dogs with pyoderma and in only 2.5% of normal dogs. Malassezia spp. were present in 15.7% of dogs, with no difference between groups. Neutrophils were observed in 12.5% of normal dogs, 30% of dogs with Malassezia dermatitis with underlying atopic dermatitis and in 70 and 80% of dogs with pyoderma and uncomplicated atopic dermatitis, respectively. Seven bacterial species were isolated from anal sacs, with no difference between normal dogs and dogs with pyoderma. In five normal animals and in four dogs with pyoderma the same bacterial strains were isolated from anal sacs and from abdominal skin and hair.

Piodermites / Pyoderma

Os autores fazem uma revisão bibliográfica da etiopatogenia, imunidade, diagnóstico e tratamento das principais manifestações dermatológicas causadas por Streptococcus pyogenes e Staphylococcus aureus

[Pyoderma gangrenosum]. / Le pyoderma gangrenosum.

Pyoderma gangrenosum is a very strange disease usually diagnosed on clinical grounds only and without any characteristic biological disturbance. It must be neither missed nor diagnosed too easily at the expense of vascular or infective ulcerations which are much more frequent. Its physiopathology remains shrouded in mystery since the abnormalities that have been found were extremely varied and sometimes conflicting, and were observed in short series. Thus, pyoderma gangrenosum appears as a syndrome which if often causeless or due to multiple diseases and might well be split into different entities in the forthcoming years. Despite its obscure pathogenesis, most patients can be cured by systemic corticosteroid therapy, sulfones or clofazimine. The main point of interest of that disease is that in almost 50 percent of the cases it is associated with a severe underlying pathology.

Selected rheumatologic and dermatologic manifestations of inflammatory bowel disease.

This review focuses on the behavior and pathogenesis of selected dermatologic and rheumatologic manifestations of inflammatory bowel disease. Erythema nodosum, the most common skin lesion, correlates with activity of the bowel disease but not with its duration or extent. Resolution occurs with therapy of inflammatory bowel disease. Pyoderma gangrenosum, the most severe skin lesion, bears little relationship to the activity or extent of the colitis. Therapy is usually supportive, but dapsone and steroids appear promising. Immune and vasculitic mechanisms have been postulated for both skin lesions. Peripheral arthritis usually has its onset with or after the development of colitic symptoms. It worsens with exacerbation of bowel inflammation and responds to treatment of the bowel disease. Immune mechanisms are likely. Spondyloarthropathy usually occurs before the onset of overt intestinal disease. Its course is unrelated to the bowel inflammation, it does not respond to treatment of bowel disease, and it is associated with HLA B27.

Pyoderma gangrenosum.

Since its description 50 years ago, pyoderma gangrenosum has continued to capture the attention and imagination of all those who see its dramatic presentation. Clinical observation still provides the only reliable diagnosis. As investigative techniques increase, more and more intriguing immunologic abnormalities associated with this disorder are discovered, but understanding of the pathogenesis remains elusive. It is now recognized as an independent condition as well as a co-condition with many systemic disorders. Many new treatment options are available, allowing much individualization of treatment. For now, pyoderma gangrenosum remains an impressive, relatively easily recognized, but poorly understood disease.

Neutrophil movement in selected canine skin diseases.

Neutrophilic movement was studied in dogs with atopy, 3 bacterial pyoderma syndromes, flea allergy dermatitis, and generalized demodicosis. Random neutrophil movement was decreased in generalized demodicosis, and this deficit correlated with the extent of body surface skin lesions. Neutrophilic chemotactic movement was decreased in 2 bacterial pyoderma syndromes: bacterial pyoderma, and staphyloccocal pyoderma. Although serum samples from diseased dogs showed no significant differences in chemoattractive qualities from normal pooled canine serum, control canine neutrophils incubated in demodectic dog serum showed decreased chemotactic responsiveness. It was postulated that demodectic dog serum had an inhibitor or deactivator of neutrophil chemotaxis.

A transient deficit in neutrophilic chemotaxis in a dog with recurrent staphylococcal pyoderma.

A transient neutrophilic chemotactic deficit was confirmed in a 3 1/2-year-old castrated male dog with recurrent staphylococcal pyoderma accompanied by a persistent eosinophilia and intermittent basophilia. Neutrophilic chemotaxis was quantitatively assessed over the next seven months, and the disappearance of the chemotactic deficit correlated with complete clinical remission of the skin lesions. Aberrations of the complement system were not discovered, and the dog's serum showed increased chemoattractiveness for control neutrophil preparations.

[The function of microphages in chronic recurrent pyodermias]. / Mikrophagenfunktion bei chronisch-rezidivierenden Pyodermien.

Polymorphonuclear leukocyte (PMNL) function tests were performed in 20 patients suffering from chronic recurrent pyogenic skin infections and, in addition, in 20 healthy individuals. As for in vitro tests, investigations of chemotaxis, intracellular killing and NADH dependent oxidase activity were included. Compared to the control group, a marked impairment of chemotaxis but totally normal microphage motility, a significantly decreased intracellular killing of ingested microorganisms by these phagocytes and an almost phagocytosis of viable and heat-inactivated Candida albicans cells could be detected in the examined patients. These results once again demonstrate the extraordinary importance of PMNL in the body's primary defense mechanisms.