A 22-year-old male presents to an outpatient clinic complaining of increasing pain and redness around a new tattoo on his left forearm, which he received three days ago. He reports the area feels warm to the touch and has become swollen. He denies fever, chills, or any other systemic symptoms. On physical examination, vital signs are stable. The tattoo site exhibits diffuse erythema, significant induration, and marked tenderness to palpation. No purulent discharge or palpable fluctuance is noted. Regional lymph nodes are not enlarged. Considering his clinical presentation, what is the most likely diagnosis and the appropriate initial outpatient management?

A 22-year-old non-verbal male patient with a history of intellectual disability and cerebral palsy, residing in a specialized care facility, is admitted to the general medical ward with acute onset of worsening left lower extremity pain and swelling over the past 12 hours. His care attendants report a recent increase in self-injurious behaviors, leading to recurrent skin integrity issues and a history of multiple prior courses of broad-spectrum antibiotics for various infections. On admission, his temperature is 39.2 °C, pulse 110 beats/min, respiratory rate 22 breaths/min, and blood pressure 105/60 mmHg. Physical examination reveals a non-ambulatory patient in a bed. The left calf and ankle are markedly erythematous, edematous, warm to touch, and exquisitely tender to palpation, with a large area of induration and several small, crusted pustular lesions visible around an excoriation site. There are also palpable inguinal lymph nodes on the left. Given these findings and the patient's background, what is the most likely diagnosis and the critical initial management strategy to prevent severe complications?

A 62-year-old man, two months post-coronary artery bypass graft (CABG) surgery, presents to the rehabilitation facility with persistent low-grade fever and localized sternal pain. He has a history of type 2 diabetes mellitus and his CABG was complicated by a sternal wound dehiscence that required surgical debridement. On examination, his temperature is 37.8°C, and there is localized erythema and tenderness over the lower sternum with a subtle underlying fluctuance; the superficial surgical wound appears well-healed. Laboratory findings include a white blood cell count of 14.5 x 10^9/L, an erythrocyte sedimentation rate (ESR) of 98 mm/hr, and a C-reactive protein (CRP) level of 125 mg/L. Two sets of blood cultures are negative. A prior sternal X-ray was inconclusive, but a subsequent nuclear bone scan strongly suggested osteomyelitis. Following this, a sternal bone biopsy was performed. While awaiting culture results, empirical vancomycin and ceftazidime were initiated. The bone biopsy culture subsequently grew Staphylococcus aureus, which was reported as sensitive to oxacillin (methicillin). Given these findings, what is the most likely confirmed diagnosis and the definitive antimicrobial management strategy?

A 7-day-old female infant is brought to a community clinic by her parents due to concerns about irritability and a spreading rash. Over the past 24 hours, the rash, which initially appeared as red patches around her neck and groin, has now progressed to involve the trunk and extremities, with some areas appearing blistered and peeling. Her parents note she has been increasingly fussy, less active, and taking fewer feeds. On examination, her temperature is 39.1°C, heart rate is 165 beats/min, respiratory rate is 28 breaths/min, and blood pressure is 85/45 mmHg. Oxygen saturation is 98% on room air. The skin shows widespread erythema with areas of superficial flaccid bullae and denudation, particularly prominent in the diaper area and flexural creases. A gentle lateral pressure on seemingly unaffected skin causes the epidermis to separate from the dermis. Her oral mucosa and conjunctiva appear normal. Given these findings, what is the most probable diagnosis and the immediate definitive therapeutic intervention required?

A 35-year-old woman presents to the emergency department complaining of acute onset nausea, persistent vomiting, and severe cramping abdominal pain. She reports these symptoms, along with two episodes of watery diarrhea, began approximately 4 hours after consuming various items from a local buffet restaurant. Her partner, who shared some of the same food, developed similar symptoms shortly thereafter. Her past medical history includes well-controlled type 2 diabetes mellitus. On physical examination, her vital signs are: temperature 37.2°C, heart rate 98 beats/min, blood pressure 118/72 mmHg, respiratory rate 16 breaths/min. There are no orthostatic changes. Abdominal palpation reveals mild, diffuse tenderness without guarding, rebound tenderness, or organomegaly. Bowel sounds are hyperactive. Capillary refill is brisk, and mucous membranes are slightly dry. Laboratory results are as follows: Considering the clinical presentation and laboratory findings, what is the most likely diagnosis and the most appropriate immediate management strategy?