American Board of Internal Medicine (ABIM) Certification Practice Exam

In cases of blastomycosis with CNS involvement, what treatment regimen is recommended?

1. Lipid formulation of amphotericin B followed by fluconazole

2. Oral fluconazole alone

3. Itraconazole for 8 weeks

4. Conventional amphotericin B

The correct answer is: Lipid formulation of amphotericin B followed by fluconazole

In cases of blastomycosis with central nervous system (CNS) involvement, the recommended treatment regimen is the lipid formulation of amphotericin B followed by fluconazole. This approach is based on the severity of the infection and the need for effective penetration into the CNS. Blastomycosis, caused by the fungus Blastomyces dermatitidis, can lead to serious complications when it involves the CNS. The lipid formulations of amphotericin B have been shown to have a better safety profile and improved distribution in body tissues, including the CNS, compared to the conventional formulation. Therefore, the use of lipid amphotericin B is important for achieving adequate therapeutic levels and minimizing toxicity. After the initial treatment with lipid amphotericin B, transitioning to fluconazole is appropriate for maintenance therapy. Fluconazole provides good CNS penetration and is effective in preventing relapse, making it the optimal choice for long-term management following an intensive initial therapy. Other options, such as oral fluconazole alone or itraconazole, may not provide sufficient initial treatment for CNS involvement in blastomycosis and do not address the need for aggressive upfront therapy in severe cases. Conventional amphotericin B, while also effective, can lead to more significant side effects and