<prompt> In the neutropenic patient, which of the following wound be most commonly encountered as a cause of bacterial meningitis and brain abscess?Pseudomonas aeruginosaStaphylococcus aureusHaemophilus influenzaeBacteroides fragilis  <response>: The pneumococcus is the most common cause of adult meningitis. In the immunocompromised patient, however, gram-negative meningitis with Pseudomonas is seen. Haemophilus influenzae is the most common cause in children over a month old. Staphylococcal meningitis is seen with penetrating head wounds. Ref: Brooks G.F. 2013. Chapter 16. Pseudomonads, Acinetobacters, and Uncommon Gram-Negative Bacteria. In G.F. Brooks Ed, Jawetz, Melnick, Adelbergs Medical Microbiology, 26e. 