In which department should a single tube of CSF obtained from a 12-month-old boy be submitted?

The single tube of cerebrospinal fluid (CSF) obtained from the 12-month-old boy should be submitted to the Microbiology department primarily because microbiological analysis is critical in diagnosing potential infections of the central nervous system, such as meningitis.

CSF analysis in microbiology typically involves culturing the fluid to identify any pathogenic organisms such as bacteria, viruses, or fungi. In infants, the risk of severe infections such as bacterial meningitis is significant, and timely microbial evaluation can lead to quicker diagnosis and treatment, which is crucial for patient outcomes.

While other departments may perform important tests on CSF, such as chemical analyses or cytological assessments, these are typically secondary considerations. The immediate need to investigate for infectious agents makes microbiology the correct department to handle CSF samples when signs of infection are suspected, especially in a pediatric patient. Therefore, the focus on identifying pathogens aligns with the typical protocols in clinical microbiology for sample processing in cases of potentially serious infections.