Staphylococcus aureus is an important human pathogen that is responsible for the vast majority of bacterial skin and soft tissue infections in humans. S. aureus can also become more invasive and cause life-threatening infections such as bacteremia, pneumonia, abscesses of various organs, meningitis, osteomyelitis, endocarditis, and sepsis. These infections represent a major public health threat due to the enormous numbers of these infections and the widespread emergence of methicillin-resistant S. aureus (MRSA) strains. MSRA is endemic in hospitals worldwide and is rapidly spreading throughout the normal human population in the community. The increasing frequency of MRSA infections has complicated treatment as these strains are more virulent and are increasingly becoming resistant to multiple different classes of antibiotics. The important role of the immune response against S. aureus infections cannot be overemphasized as humans with certain genetic and acquired immunodeficiency disorders are at an increased risk for infection. Understanding the cutaneous immune responses against S. aureus is essential as most of these infections occur or originate from a site of infection or colonization of the skin and mucosa. This review will summarize the innate immune responses against S. aureus skin infections, including antimicrobial peptides that have direct antimicrobial activity against S. aureus as well as pattern recognition receptors and proinflammatory cytokines that promote neutrophil abscess formation in the skin, which is required for bacterial clearance. Finally, we will discuss the recent discoveries involving IL-17-mediated responses, which provide a key link between cutaneous innate and adaptive immune responses against S. aureus skin infections.

Staphylococcus aureus is responsible for the vast majority of bacterial skin infections in humans. The propensity for S. aureus to infect skin involves a balance between cutaneous immune defense mechanisms and virulence factors of the pathogen. The tissue architecture of the skin is different than other epithelia especially since it possesses a corneal layer, which is an important barrier that protects against the pathogenic microorganisms in the environment. The skin surface, epidermis and dermis each contribute to host defense against S. aureus. Conversely, S. aureus utilizes various mechanisms to evade these host defenses to promote colonization and infection of the skin. This review will focus on host-pathogen interactions at the skin interface during the pathogenesis of S. aureus colonization and infection.

Acute generalized exanthematous pustulosis (AGEP) is an acute drug eruption characterized by erythematous plaques and papules studded with numerous, pinpoint pustules. Several atypical clinical presentations and triggers of AGEP have been described in the literature. These include systemic presentations similar to toxic epidermal necrolysis (TEN) and drug-induced hypersensitivity syndrome (DIHS) and localized presentations mimicking other medication reactions. We herein aim to review atypical presentations and medication triggers of AGEP to assist clinicians in recognizing this condition and making appropriate therapeutic interventions.

Nonperinatal listeriosis-associated deaths in the United States have decreased, paralleling a decreasing trend in incidence. Strict monitoring of food manufacturing processes, as well as improved treatment for HIV infection, may have played influential roles in preventing human infections. Health care providers should be aware of seasonal listeriosis patterns, as well as conditions predisposing individuals to severe infection and death due to L. monocytogenes infection, to guide strategies for disease management and prevention.

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