| Gram-Positive Bacteria |
| COCCI |
| Staphylococcus |
| Bacteria | Disease | Treatment |
| Staphylococcus aureus | Abscesses and mastitisEndocarditisGastroenteritisOsteomyelitisPneumoniaScalded skin syndromeSkin infectionsToxic shock syndrome | Penicillinase-resistant penicillinsVancomycinLinezolid |
| Staphylococcus epidermidis | Normal skin and genital tract floraAssociated with use of catheters and prosthetic devices and biofilm development | Vancomycin |
| Staphylococcus saprophyticus | Normal genital tract floraUrinary tract infection | Trimethoprim-sulfamethoxazole |
| Streptococcus |
| Streptococcus pneumoniae | “MOPS” Meningitis Otitis media Pneumonia Sinusitis | Penicillins3rd generation cephalosporins |
| Streptococcus pyogenes (Group A) | Pyogenic infectionspharyngitiscellulitisimpetigoerysipelasToxigenic infectionsscarlet fevernecrotizing fasciitisImmunologic infectionsglomerulonephritisrheumatic fever | Penicillins |
| Streptococcus agalactiae (Group B) | Normal vaginal floraNeonatal septicemiaNeonatal meningitis | Ampicillin |
| Streptococcus viridans | Normal throat floraDental cariesEndocarditis | Penicillin G |
| Streptococcus bovis (Group D) | Normal gut floraBacteremiaEndocarditis (subacute)Associated with colon cancer | Penicillin or ceftriaxone |
| Enterococci |
| Enterococci faecalis (Group D) | Normal gut floraEndocarditis (subacute)Urinary tract infectionBiliary tract infections | Some strains are vancomycin-resistant (VRE)Linezolid and streptograminsPenicillins, vancomycin, or daptomycinOften resistant to penicillin G |
| BACILLI |
| Spore-Forming |
| Bacillus anthracis | Cutaneous anthraxPulmonary anthrax | CiprofloxacinDoxycycline |
| Bacillus cereus | Food poisoning (rice) | Self-limitingClindamycinAminoglycosides |
| Clostridium tetani | Tetanus | Antitoxin with or without vaccine boosterBenzodiazepines for muscle spasmsSurgical debridement |
| Clostridium botulinum | Botulism | Human botulinum immunoglobulin |
| Clostridium perfringens | Gas gangreneFood poisoning | ClindamycinPenicillin |
| Clostridium difficile | Antibiotic-associated diarrheaColitisPseudomembranous colitis | MetronidazoleVancomycin (oral)FidaxomicinFecal microbiota transplant |
| Non-Spore Forming |
| Corynebacterium diphtheriae | Diphtheria | ErythromycinPenicillin GDiphtheria antitoxin |
| Listeria monocytogenes | MeningitisneonatalimmunocompromisedAmnionitisSpontaneous abortionGranulomatosis infantisepticaGastroenteritis | AmpicillinTrimethoprim-sulfamethoxazole |
| BRANCHING FILAMENTS |
| Nocardia spp. | Pulmonary infection (immunocompromised)Cutaneous nocardiosis (associated with trauma) | Trimethoprim-sulfamethoxazoleCarbapenems |
| Actinomyces spp. | Oral and facial abscessesassociated with poor dental hygiene or maxillofacial traumaYellow “sulfur granules”Pelvic inflammatory diseaseassociated with intrauterine devices | PenicillinTetracycline |
