Recurrent necrotizing fasciitis caused by methicillin-resistant Staphylococcus aureus

Early surgery for limb preservation in Group A Streptococcus-induced necrotizing soft tissue infection and subsequent soft tissue infection: A case report

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This is a case of necrotizing soft tissue infection (NSTI) due to S. pyogenes.

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Exploration and subsequent debridement led to the limb preservation.

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Early surgery is crucial for effective treatment of NSTI.

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Non-necrotizing STI due to S. pyogenes could be possible to reccure at the same limb 2 months later.

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The patient received antimicrobial treatment without surgery and recovered.

Background

Group A Streptococcus pyogenes (GAS) causes necrotizing soft tissue infections (NSTIs) necessitating exploration, surgical debridement, and possibly limb amputation.

Case presentation

A 45-year-old man presented with traumatic injury of the left carpal region, vomiting, and diarrhea. The swelling and pain in the left forearm worsened with sensorimotor deficits, and his skin color deteriorated. Emergent exploration was performed for limb preservation; GAS was detected in an exudate, and debridement was performed on postoperative day 2 for streptococcal toxic shock syndrome. He recovered uneventfully and was discharged; however, he returned after 2 months with GAS-induced STI at the same site and received antimicrobial treatment.

Conclusion

Exploration and subsequent debridement are crucial for effective treatment of NSTI.

Macrophage-derived LTB4 promotes abscess formation and clearance of Staphylococcus aureus skin infection in mice

The early events that shape the innate immune response to restrain pathogens during skin infections remain elusive. Methicillin-resistant Staphylococcus aureus (MRSA) infection engages phagocyte chemotaxis, abscess formation, and microbial clearance. Upon infection, neutrophils and monocytes find a gradient of chemoattractants that influence both phagocyte direction and microbial clearance. The bioactive lipid leukotriene B4 (LTB4) is quickly (seconds to minutes) produced by 5-lipoxygenase (5-LO) and signals through the G protein-coupled receptors LTB4R1 (BLT1) or BLT2 in phagocytes and structural cells. Although it is known that LTB4 enhances antimicrobial effector functions in vitro, whether prompt LTB4 production is required for bacterial clearance and development of an inflammatory milieu necessary for abscess formation to restrain pathogen dissemination is unknown. We found that LTB4 is produced in areas near the abscess and BLT1 deficient mice are unable to form an abscess, elicit neutrophil chemotaxis, generation of neutrophil and monocyte chemokines, as well as reactive oxygen species-dependent bacterial clearance. We also found that an ointment containing LTB4 synergizes with antibiotics to eliminate MRSA potently. Here, we uncovered a heretofore unknown role of macrophage-derived LTB4 in orchestrating the chemoattractant gradient required for abscess formation, while amplifying antimicrobial effector functions.

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.

Severe necrotizing fasciitis in a human immunodeficiency virus-positive patient caused by methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a rarely reported cause of necrotizing fasciitis. We report an unusually severe case of MRSA necrotizing fasciitis in a previously undiagnosed AIDS patient. Molecular analysis revealed that the strain had the USA300/spa1 genotype, now an abundant cause of community-acquired MRSA infection.

Necrotizing fasciitis due to a methicillin-sensitive Staphylococcus aureus isolate harboring an enterotoxin gene cluster

Benign papular eruption on the left leg of a 72-year-old diabetic man developed into rapidly spreading necrotizing fasciitis despite antimicrobial therapy and surgical debridements. This led to eventual amputation to control the infection. The etiological agent was a Staphylococcus aureus isolate harboring the enterotoxin gene cluster seg, sei, sem, sen, and seo but lacked all common toxin genes, including Panton-Valentine leukocidin.