Necrotizing Fasciitis

(SBQ18FA.43) A 36-year-old man with HIV, chronic kidney failure, and chronic IV drug use presents with worsening fevers, chills, and purulent drainage from his leg. His infection progresses rapidly and he becomes acutely septic. He is therefore taken urgently to the OR for radical debridement of the fascia and surrounding tissues, with a plan for delayed closure. His CRP is 90 mg/dL and he is hyponatremic. Intraoperative cultures are obtained. To cover the most common organism(s) associated with this condition, what antibiotic would you initially recommend?

(SBQ18FA.41) Figures 1 and 2 are the radiographs of a 41-year-old diabetic male presenting with right lower extremity pain after cutting his leg it on a piece of rusty metal yesterday. Serial physical exam demonstrates rapid progression of the overlying erythema and worsening pain. In the emergency department, labs are significant for a C-reactive protein (CRP) of 180 mg/L, white blood cell (WBC) count of 19,000/mm3, glucose of 11 mmol/L, creatinine of 150 umol/L, and sodium of 120 mmol/L. He has a temperature of 102°F and a heart rate of 110 bpm. What additional laboratory value is needed to calculate this patient’s LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) score?

(OBQ04.217) A 52-year-old diabetic male sustained minor blunt trauma to his left thigh 10 hours prior to presentation. He initially complained of extreme thigh pain with erythema and swelling but rapidly developed bullae and worsening erythema over the affected area along with fever and tachycardia. A clinical photo is shown in Figure A. What clinical factor has been shown to reduce mortality when treating this pathology?

(OBQ04.264) A 56-year-old diabetic male presents to the emergency department by ambulance after developing high-grade fevers, malaise, and altered mental status. Upon presentation, he is found to be hypotensive and initial labs show an elevated WBC with a profound left shift. Figure A shows skin manifestations confined to the foot at initial presentation. He is started on broad spectrum antibiotics. Upon follow-up exam 3 hours later his clinical condition deteriorates (Figure B) and he is taken to the operating room for surgical debridement. In a bacterial culture, what would be the most common single isolate for this condition?