Soru

A $32$-year-old female patient is assessed on hospital day $4$. She was initially admitted for high fevers, rigors, and pleuritic chest pain. Her past medical history is significant for major depressive disorder managed with citalopram, and severe opioid use disorder. On the day of admission, physical examination revealed a pan-systolic murmur at the left lower sternal border that augmented during inspiration. Blood cultures from admission grew methicillin-susceptible *Staphylococcus aureus* (MSSA). A transthoracic echocardiogram showed a $1.6$-cm oscillating mass on the tricuspid valve. She was appropriately started on targeted therapy with continuous intravenous nafcillin.

Currently, she reports mild improvement in her chest pain but notes a persistent cough. Her temperature is $37.9^\circ \text{C}$ ($100.2^\circ \text{F}$), blood pressure is $114/70$ mmHg, pulse is $92$/min, and respiratory rate is $18$/min. Pulse oximetry shows $95\%$ on room air. Auscultation of the lungs reveals coarse crackles in the periphery of both lung fields. The cardiac examination is unchanged from admission. There is no jugular venous distention and no peripheral edema.

Laboratory tests reveal:
Leukocyte count: $12,200$/mm $^3$
Thyroid-stimulating hormone (TSH): $1.4\ \mu\text{U/mL}$ (Normal: $0.5 - 5.0\ \mu\text{U/mL}$)
Free thyroxine (T4): $1.1\ \text{ng/dL}$ (Normal: $0.9 - 1.7\ \text{ng/dL}$)
Total triiodothyronine (T3): $62\ \text{ng/dL}$ (Normal: $80 - 200\ \text{ng/dL}$)

A repeat chest radiograph demonstrates several new, small cavitary lesions scattered throughout the peripheral lung fields bilaterally.

Which of the following is the most appropriate next step in the management of this patient?