<prompt> The most common organism amongst the following that causes acute meningitis in an AIDS patients is a-Streptococcus pneumoniaeStreptococcus agalactiaeCryptococcus neoformansListeria monocytogenes  <response>: C. neoformans infection - most common in patients with advanced HIV infection with CD4 T-cell counts 200ml Meningitis in Neonates or infants of 0-2 months: Escherichia coli Group B streptococcus S. agalactiae Listeria monocytogenes Overall Aseptic meningitis: Cryptococcus neoformans.. Capsular antigen detection from CSF or serum by latex agglutination test is a rapid and sensitive 95. 