Infectious Diseases II
considered in the medical treatment of prosthetic valve
endocarditis (Answer B is incorrect). Because the
patient is responding to current vancomycin therapy,
an escalation to daptomycin is inappropriate right now
(Answer C is incorrect).
Answer: B
This patient is admitted to the ICU for an indication that
is unrelated to the patient’s underlying HIV. The assess-
ment of which prophylactics are necessary against OIs
depends on the patient’s underlying disease, history, and
CD4+ count. In this case, the patient has a CD4+ count
less than 100/mm3 and a history of cryptococcal men-
ingitis. Hence, prophylaxis should be administered for
toxoplasmosis, P. jiroveci, and Cryptococcus. The best
regimen for this patient is fluconazole 200 mg daily and
trimethoprim/sulfamethoxazole 1 DS tablet once daily
(Answer B is correct). The prophylaxis for M avium
complex is indicated for patients with a CD4+ count
of less than 50 cells/mm3, which is unnecessary at this
point (Answers A and C are incorrect). Although trim-
ethoprim/sulfamethoxazole 1 DS tablet thrice weekly is
an option for prophylaxis, it is not the best choice against
toxoplasmosis (Answer D is incorrect).
Answer: B
This patient has invasive pulmonary aspergillosis.
Usually, the treatment of choice is voriconazole.
However, in this case, the patient has acute kidney
injury with a CrCl less than 50 mL/minute/1.73 m2.
According to the package insert, voriconazole is
contraindicated in this case because of the possibility
of accumulation of cyclodextrin, the intravenous drug
carrier for voriconazole. Although the clinical relevance
of this accumulation is controversial, continued use
of a contraindicated therapy is inappropriate when
alternatives may be available (Answer D is incorrect).
Isavuconazole is a new triazole that was found to
be noninferior to voriconazole for the treatment of
aspergillosis and has improved water solubility, which
does not require it to be formulated with cyclodextrin
(Answer B is correct). Conventional amphotericin may
be a reasonable choice, but it will likely worsen the
patient’s acute kidney injury (Answer A is incorrect).
Echinocandins are not the ideal therapies for invasive
aspergillosis and should only be considered if there are
no other treatment options. In addition, caspofungin
can decrease the serum concentration of tacrolimus
(Answer C is incorrect).