**Question 128:**
A patient presents with neck stiffness and fever. CSF analysis shows elevated protein levels, decreased glucose levels, and an increased white blood cell count with 70% polymorphs. What is the most likely cause?
A. Cryptococcus neoformans
B. Tuberculosis
C. Viral infection
D. Bacterial infection
E. Fungal infection
**Correct Answer:** D. Bacterial infection
**Explanation:** The CSF analysis results indicate a bacterial infection as the most likely cause. Elevated protein, decreased glucose, and a high percentage of polymorphonuclear leukocytes (PMNs) are typical of bacterial meningitis. Viral infections usually show normal or slightly elevated protein levels, normal glucose, and a lymphocytic predominance in the white blood cell count. Cryptococcus and tuberculosis can also cause meningitis, but the CSF findings here are more suggestive of a bacterial origin.