American Board of Internal Medicine (ABIM) Certification Practice Exam

In patients with pulmonary cryptococcosis, what is the next step even without CNS symptoms?

1. Start antifungal treatment

2. Perform a lung biopsy

3. Perform a lumbar puncture

4. Initiate broad-spectrum antibiotics

The correct answer is: Perform a lumbar puncture

In patients with pulmonary cryptococcosis, the presence or absence of CNS symptoms does not negate the importance of assessing for potential central nervous system involvement. Cryptococcus neoformans is known for disseminating to the CNS, and even in the absence of symptoms such as headaches, altered mental status, or other neurological signs, the risk of meningitis or cryptococcal infection of the CNS remains high. Therefore, performing a lumbar puncture is a critical next step, as it allows for the direct assessment of the cerebrospinal fluid (CSF) to detect cryptococcal infection, which can include examining for cryptococcal antigen and performing a culture. By conducting the lumbar puncture, clinicians can confirm or rule out CNS involvement, which is essential for determining the appropriate treatment plan and managing the patient's risk of complications associated with cryptococcal disease. Initiating antifungal treatment, while important, should ideally follow confirmation of the diagnosis through lumbar puncture results.