| Age | Pathogens | |
| Neonate (118) |
Proteus Citrobacter Enterobacter |
|
| Child (55, 132) |
Streptococcus (aerobic and anaerobic) 60-70% Gram negative anaerobic 20-40% Enterobacter Staphylococcus 10-15% |
|
| Route of Infection | Condition | Pathogens |
| Hematogenous | ||
| Congenital heart disease |
Streptococcus viridans Staphylococcus aureus Streptococcus (aerobic and microaerophillic) Haemophilus sp. |
|
| Endocarditis |
Staphylococcus aureus Streptococcus (aerobic and microaerophillic) |
|
| Bacteremia |
Staphylococcus aureus Streptococcus (aerobic and microaerophillic) Gram negative anaerobic bacilli |
|
| Pulmonary infection |
Streptococcus (aerobic and anaerobic) Nocardia Gram negative anaerobic bacilli Fusobacterium Actinomyces |
|
| Skin folliculitis |
Staphylococcus aureus Streptococcus |
|
| Osteomyelitis |
Staphylococcus aureus Enterobacter Streptococcus Haemophilus sp. |
|
| Pulmonary foreign body (aspiration) |
Streptococcus (aerobic and anaerobic) Gram negative anaerobic bacilli Nocardia Fusobacterium Actinomyces |
|
| Contiguous | ||
| Otitis media |
Streptococcus (aerobic and anaerobic) Enterobacter Pseudomonas Provetella Bacteroides |
|
| Sinus infection |
Streptococcus (aerobic and anaerobic) Enterobacter Pseudomonas Fusobacterium Bacteroides Haemophilus sp. |
|
| Meningitis |
Staphylococcus Gram negative bacilli Streptococcus Listeria Haemophilus sp. |
|
| Dental infection |
Mixed anaerobes Streptococcus (aerobic and anaerobic) Staphylococcus aureus Enterococcus |
|
| Trauma | ||
| Penetrating cranial injury |
Streptococcus Staphylococcus Enterococcus Mycobacterium Bacteroides Clostridium |
|
| Neurosurgical procedure |
Staphylococcus Pseudomonas Enterococcus |
|
| Immunological Status | Pathogens | |
| Immunocompromised |
Nocardia Mycobacteria (TB) Gram negative anaerobic bacilli Asperillus Candida Enterobacter Cryptococcus Toxoplasma gondii Mucorales Listeria |
(Adapted from 31, 51)