Skin and Soft Tissue Infections

A 42-year-old male farmer from rural Maharashtra presents with a 3-day history of rapidly spreading erythema, edema, and warmth over his left leg following a minor cut while working in the field. On examination, he has a temperature of 38.5°C, tachycardia (HR 110/min), and poorly demarcated erythema with brawny edema extending from the ankle to mid-thigh. There is no fluctuance or abscess formation. Blood cultures are pending. Which is the most likely causative organism and the immediate management?

A 38-year-old diabetic woman from Delhi presents with a 5-day history of pain, swelling, and foul-smelling discharge from her left foot following a puncture wound from a contaminated needle. On examination, she has a temperature of 39.2°C, tachycardia (HR 115/min), and a necrotic ulcer with surrounding erythema and crepitus on palpation. Blood glucose is 320 mg/dL. Gram stain of the wound discharge shows mixed flora including gram-positive cocci and gram-negative rods. What is the most appropriate initial management?

Which organism is the most common causative agent of necrotizing fasciitis Type I?