Which staining method is usually used for cerebrospinal fluid smears?

When analyzing cerebrospinal fluid (CSF) smears, both Gram stain and India ink stain are employed for different purposes. The Gram stain is crucial for identifying bacterial pathogens in the CSF. By differentiating bacteria into two groups (Gram-positive and Gram-negative), the Gram stain helps in the initial diagnosis of bacterial meningitis and other infections.

The India ink stain is specifically used to visualize encapsulated organisms, most notably Cryptococcus neoformans. This fungus is a common cause of meningitis in immunocompromised patients, and its large, mucopolysaccharide capsule can be seen clearly against the black background provided by the India ink preparation.

Given the importance of both methods in diagnosing infections that can be detected through CSF analysis, it is accurate to state that both the Gram stain and the India ink stain are routinely used in this context.