[Expert Solution]: A 30-year-old male is admitted to the…

A 30-year-old male is admitted to the intensive care unit after his wife found him unconscious at home Laboratory studies show a serum pH of 7.10 and positive serum ketones His mucus membranes are extremely dry. The wife notes that he has lost a significant amount of weight recently despite eating and drinking the normal amounts. Treatment is initiated, and the patient’s pH improves. However, he now complains of fever, headache, and eye pain Examination of the nasal cavity reveals black necrotic eschar adherent to the inferior turbinate. Which of the following procedures would likely confirm the diagnosis? Lumbar puncture Blood cultures Mucosal biopsy Serologic testing Ophthalmoscopy