Coagulase negative staphylococci are skin commensals and are generally disregarded as contaminants in clinical specimens. Repeated isolation of coagulase negative staphylococci in blood cultures should warrant a species identification to recognize unusually virulent organisms that demand aggressive treatment, such as Staphylococcus lugdunensis. Staphylococcus lugdunensis is known to cause a wide variety of infections, including a predominant left-sided endocarditis. We report a rare case of native tricuspid valve Staphylococcus lugdunensis endocarditis in a non-intravenous drug user and include a brief literature review.KEY WORDS: Staphylococcus lugdunensis; coagulase negative staphylococci; skin commensals; left-sided endocarditis.

Vaping or E-cigarettes were created to deliver nicotine-containing aerosol to users with a flavoring agent without agents such as tars, oxidant gases, and carbon monoxide smoke found in traditional tobacco cigarettes. The use of E-cigarettes is steadily increasing in the United States, especially among the young population. Electronic cigarettes seem capable of causing various injury patterns in the lungs, collectively called E-cigarettes or vaping-associated lung injury (EVALI). Spontaneous pneumomediastinum (SPM) is a rare finding in EVALI. Here, we report a case of spontaneous pneumomediastinum secondary to vaping in a young man with no past medical history except for daily vaping and a recent untreated influenza infection.

A 56-year-old male was admitted to the hospital with severe sepsis secondary to pneumonia. His presentation was challenging and confusing due to the accompanying coronavirus disease 2019 (COVID-19) infection attributed to his travel history and diagnosed via radiological findings. He received dexamethasone with ceftriaxone and azithromycin. Despite the fact he was on appropriate antibiotics, his condition worsened, and he was eventually diagnosed with Legionella pneumonia, which was thought to be resistant to macrolides. His condition improved significantly when antibiotics were switched to levofloxacin. It is important to keep in mind other causes of community-acquired pneumonia (CAP) during the ongoing COVID-19 era. What makes this case unique is that it presented a confusing scenario due to the patient's concurrent COVID-19 infection and his failure to improve with the administration of azithromycin.

Multidrug-resistant enterococcal nosocomial invasive infections are a rising concern faced by the medical community. Not many options are available to treat these highly virulent organisms. Risk factors for developing these highly resistant organisms include prolonged hospital stay, previous antibiotic use, and immunosuppression. In this article, we report a case of daptomycin-resistant enterococcal native infective endocarditis treated with off-label use of quinupristin-dalfopristin.