Necrotizing fasciitis caused by Staphylococcus aureus

Treatment Strategies for Infected Wounds

The treatment of skin wounds is a key research domain owing to the important functional and aesthetic role of this tissue. When the skin is impaired, bacteria can soon infiltrate into underlying tissues which can lead to life-threatening infections. Consequently, effective treatments are necessary to deal with such pathological conditions. Recently, wound dressings loaded with antimicrobial agents have emerged as viable options to reduce wound bacterial colonization and infection, in order to improve the healing process. In this paper, we present an overview of the most prominent antibiotic-embedded wound dressings, as well as the limitations of their use. A promising, but still an underrated group of potential antibacterial agents that can be integrated into wound dressings are natural products, especially essential oils. Some of the most commonly used essential oils against multidrug-resistant microorganisms, such as tea tree, St. John's Wort, lavender and oregano, together with their incorporation into wound dressings are presented. In addition, another natural product that exhibits encouraging antibacterial activity is honey. We highlight recent results of several studies carried out by researchers from different regions of the world on wound dressings impregnated with honey, with a special emphasis on Manuka honey. Finally, we highlight recent advances in using nanoparticles as platforms to increase the effect of pharmaceutical formulations aimed at wound healing. Silver, gold, and zinc nanoparticles alone or functionalized with diverse antimicrobial compounds have been integrated into wound dressings and demonstrated therapeutic effects on wounds.

Staphylococcal and streptococcal superantigen exotoxins

SUMMARY This review begins with a discussion of the large family of Staphylococcus aureus and beta-hemolytic streptococcal pyrogenic toxin T lymphocyte superantigens from structural and immunobiological perspectives. With this as background, the review then discusses the major known and possible human disease associations with superantigens, including associations with toxic shock syndromes, atopic dermatitis, pneumonia, infective endocarditis, and autoimmune sequelae to streptococcal illnesses. Finally, the review addresses current and possible novel strategies to prevent superantigen production and passive and active immunization strategies.

Recent advances in the treatment of necrotizing fasciitis

With four types of necrotizing fasciitis (NF) now recognized, the diagnosis and management of NF becomes more challenging as physicians face more unusual pathogenic and atypical presentations. With few published guidelines and little evidence base to justify therapies, much of the literature is pragmatic or provides limited evidence with small underpowered studies and disparate case reports.

Necrotizing fasciitis: manifestations, microbiology and connection with black tar heroin

A 10-year review of records of the King County Medical Examiner's Office found 87 deaths due to necrotizing fasciitis and related necrotizing soft tissue infections. In 64 of these cases there were sufficient details to provide an analysis of the manifestations, microbiology, and source of infection. One half (32) of the cases were due to injection of black tar heroin, the nearly exclusive form of heroin in the Northwest United States. Of those due to black tar injection, 24 were clostridial infections with various species represented, eight of which were Clostridium sordellii. Of the 32 cases not associated with drug injection, streptococcal species predominated, with Streptococcus pyogenes isolated in 14 cases. Only three of 32 cases not associated with injection drug use were clostridial infections. These differences were statistically significant. Staphylococcus aureus was isolated from 14 cases; two were methicillin-resistant strains. Overall, 28 of the 64 cases were polymicrobial infections, 15 due to black tar injection and 13 not associated with drug injection. This study supports the conclusion that necrotizing fasciitis due to black tar heroin injection is predominantly a clostridial disease, and in this way differs significantly from necrotizing fasciitis due to other causes.

Recurrent necrotizing fasciitis caused by methicillin-resistant Staphylococcus aureus

Reported here is a rare case of recurrent necrotizing fasciitis due to methicillin-resistant Staphylococcus aureus (MRSA). A 46-year-old female with poorly controlled diabetes and chronic ingestion of steroid-containing medications was admitted for treatment of necrotizing fasciitis of the right thigh. Three months following hospital discharge she was readmitted with necrotizing fasciitis of the left hand. On both occasions, MRSA was isolated from tissue cultures obtained during surgical debridement. Patients who develop necrotizing fasciitis are predisposed to severe soft tissue infections due to associated comorbid conditions such as diabetes mellitus. Recurrent soft tissue infection in a patient with previous MRSA-related necrotizing fasciitis should therefore be treated with a high index of suspicion.

Wound microbiology and associated approaches to wound management

The majority of dermal wounds are colonized with aerobic and anaerobic microorganisms that originate predominantly from mucosal surfaces such as those of the oral cavity and gut. The role and significance of microorganisms in wound healing has been debated for many years. While some experts consider the microbial density to be critical in predicting wound healing and infection, others consider the types of microorganisms to be of greater importance. However, these and other factors such as microbial synergy, the host immune response, and the quality of tissue must be considered collectively in assessing the probability of infection. Debate also exists regarding the value of wound sampling, the types of wounds that should be sampled, and the sampling technique required to generate the most meaningful data. In the laboratory, consideration must be given to the relevance of culturing polymicrobial specimens, the value in identifying one or more microorganisms, and the microorganisms that should be assayed for antibiotic susceptibility. Although appropriate systemic antibiotics are essential for the treatment of deteriorating, clinically infected wounds, debate exists regarding the relevance and use of antibiotics (systemic or topical) and antiseptics (topical) in the treatment of nonhealing wounds that have no clinical signs of infection. In providing a detailed analysis of wound microbiology, together with current opinion and controversies regarding wound assessment and treatment, this review has attempted to capture and address microbiological aspects that are critical to the successful management of microorganisms in wounds.