Host problem | Organism favored | Frequency of defect actually leading to infection |
Absence of opsonizing antibody | Streptococcus pneumoniae | Common in all age groups |
Haemophilus influenzae | Common in very young children |
Asplenia: surgical or functional | S. pneumoniae | Rare |
Neisseria meningitidis | Very rare |
Complement deficiency | N. meningitidis | Very rare |
Glucocorticoid excess | Listeria monocytogenes | Rare |
Cryptococcus neoformans | Rare |
HIV infection | C. neoformans | About 5 percent eventually get cryptococcal meningitis |
S. pneumoniae | Common presenting illness |
L. monocytogenes | Rare |
Bacteremia/endocarditis | Staphylococcus aureus; various gram-negative rods | Rare |
Basilar skull fracture | S. pneumoniae; other upper respiratory tract flora | Very rare |