Book contents
- Frontmatter
- Dedication
- Contents
- List of Contributors
- Preface
- Part I Clinical syndromes: general
- Part II Clinical syndromes: head and neck
- Part III Clinical syndromes: eye
- Part IV Clinical syndromes: skin and lymph nodes
- Part V Clinical syndromes: respiratory tract
- Part VI Clinical syndromes: heart and blood vessels
- Part VII Clinical syndromes: gastrointestinal tract, liver, and abdomen
- Part VIII Clinical syndromes: genitourinary tract
- Part IX Clinical syndromes: musculoskeletal system
- Part X Clinical syndromes: neurologic system
- Part XI The susceptible host
- Part XII HIV
- Part XIII Nosocomial infection
- Part XIV Infections related to surgery and trauma
- Part XV Prevention of infection
- Part XVI Travel and recreation
- Part XVII Bioterrorism
- Part XVIII Specific organisms: bacteria
- 123 Actinomycosis
- 124 Anaerobic infections
- 125 Anthrax and other Bacillus species
- 126 Bartonella bacilliformis
- 127 Cat scratch disease and other Bartonella infections
- 128 Bordetella
- 129 Branhamella–Moraxella
- 130 Brucellosis
- 131 Campylobacter
- 132 Clostridium
- 133 Corynebacteria
- 134 Enterobacteriaceae
- 135 Enterococcus
- 136 Erysipelothrix
- 137 HACEK
- 138 Helicobacter pylori
- 139 Gonococcus: Neisseria gonorrhoeae
- 140 Haemophilus
- 141 Legionellosis
- 142 Leprosy
- 143 Meningococcus and miscellaneous neisseriae
- 144 Listeria
- 145 Nocardia
- 146 Pasteurella multocida
- 147 Pneumococcus
- 148 Pseudomonas, Stenotrophomonas, and Burkholderia
- 149 Rat-bite fevers
- 150 Salmonella
- 151 Staphylococcus
- 152 Streptococcus groups A, B, C, D, and G
- 153 Viridans streptococci
- 154 Poststreptococcal immunologic complications
- 155 Shigella
- 156 Tularemia
- 157 Tuberculosis
- 158 Nontuberculous mycobacteria
- 159 Vibrios
- 160 Yersinia
- 161 Miscellaneous gram-positive organisms
- 162 Miscellaneous gram-negative organisms
- Part XIX Specific organisms: spirochetes
- Part XX Specific organisms: Mycoplasma and Chlamydia
- Part XXI Specific organisms: Rickettsia, Ehrlichia, and Anaplasma
- Part XXII Specific organisms: fungi
- Part XXIII Specific organisms: viruses
- Part XXIV Specific organisms: parasites
- Part XXV Antimicrobial therapy: general considerations
- Index
- References
152 - Streptococcus groups A, B, C, D, and G
from Part XVIII - Specific organisms: bacteria
Published online by Cambridge University Press: 05 April 2015
- Frontmatter
- Dedication
- Contents
- List of Contributors
- Preface
- Part I Clinical syndromes: general
- Part II Clinical syndromes: head and neck
- Part III Clinical syndromes: eye
- Part IV Clinical syndromes: skin and lymph nodes
- Part V Clinical syndromes: respiratory tract
- Part VI Clinical syndromes: heart and blood vessels
- Part VII Clinical syndromes: gastrointestinal tract, liver, and abdomen
- Part VIII Clinical syndromes: genitourinary tract
- Part IX Clinical syndromes: musculoskeletal system
- Part X Clinical syndromes: neurologic system
- Part XI The susceptible host
- Part XII HIV
- Part XIII Nosocomial infection
- Part XIV Infections related to surgery and trauma
- Part XV Prevention of infection
- Part XVI Travel and recreation
- Part XVII Bioterrorism
- Part XVIII Specific organisms: bacteria
- 123 Actinomycosis
- 124 Anaerobic infections
- 125 Anthrax and other Bacillus species
- 126 Bartonella bacilliformis
- 127 Cat scratch disease and other Bartonella infections
- 128 Bordetella
- 129 Branhamella–Moraxella
- 130 Brucellosis
- 131 Campylobacter
- 132 Clostridium
- 133 Corynebacteria
- 134 Enterobacteriaceae
- 135 Enterococcus
- 136 Erysipelothrix
- 137 HACEK
- 138 Helicobacter pylori
- 139 Gonococcus: Neisseria gonorrhoeae
- 140 Haemophilus
- 141 Legionellosis
- 142 Leprosy
- 143 Meningococcus and miscellaneous neisseriae
- 144 Listeria
- 145 Nocardia
- 146 Pasteurella multocida
- 147 Pneumococcus
- 148 Pseudomonas, Stenotrophomonas, and Burkholderia
- 149 Rat-bite fevers
- 150 Salmonella
- 151 Staphylococcus
- 152 Streptococcus groups A, B, C, D, and G
- 153 Viridans streptococci
- 154 Poststreptococcal immunologic complications
- 155 Shigella
- 156 Tularemia
- 157 Tuberculosis
- 158 Nontuberculous mycobacteria
- 159 Vibrios
- 160 Yersinia
- 161 Miscellaneous gram-positive organisms
- 162 Miscellaneous gram-negative organisms
- Part XIX Specific organisms: spirochetes
- Part XX Specific organisms: Mycoplasma and Chlamydia
- Part XXI Specific organisms: Rickettsia, Ehrlichia, and Anaplasma
- Part XXII Specific organisms: fungi
- Part XXIII Specific organisms: viruses
- Part XXIV Specific organisms: parasites
- Part XXV Antimicrobial therapy: general considerations
- Index
- References
Summary
Classification
In the early 1950s, Lancefield divided streptococci into groups based on carbohydrates present in the cell wall and designated the groups A through H and K through T. In addition, streptococci may be classified by their characteristics on culture on sheep blood agar. β-Hemolytic streptococci produce zones of clear hemolysis around each colony; α-hemolytic streptococci (Streptococcus viridans) produce a green discoloration characteristic of incomplete hemolysis; absence of hemolysis is characteristic of γ-streptococci.
Pharyngitis
The sole member of Lancefield group A is Streptococcus pyogenes. Group A streptococcus is ubiquitous in the environment but with rare exceptions is exclusively found in or on the human host. About 5% to 20% of the population harbor group A streptococcus in their pharynx, and some are colonized on their skin. This organism produces a variety of suppurative infections; however, streptococcal pharyngitis, the most common, is characterized by the onset of sore throat, fever, painful swallowing, and chilliness. These symptoms combined with submandibular adenopathy, pharyngeal erythema, and exudates correlate with positive throat cultures in 85% to 90% of cases. Sore throat without fever or any of the other signs and symptoms has a low predictive value for pharyngitis caused by group A streptococcus. Rapid strep tests correlate with positive cultures in 68% to 99% of cases, but results depend greatly on the individual performing the test as well as the bacterial colony count. Colony counts greater than 100 per plate correlated with positive rapid strep tests in 95% of patients, and counts less than 100 per plate correlated with positive rapid strep tests for only 68% of patients.
- Type
- Chapter
- Information
- Clinical Infectious Disease , pp. 991 - 996Publisher: Cambridge University PressPrint publication year: 2015