Difference between revisions of "Category:Streptococcus species"
Jump to navigation
Jump to search
| Line 18: | Line 18: | ||
*Haemolytic streptococci of Lancefield group C are common inhabitants of the equine nasopharynx | *Haemolytic streptococci of Lancefield group C are common inhabitants of the equine nasopharynx | ||
*''Streptococcus zooepidemicus'' and ''S. equisimilis'' are usually non-pathogenic | *''Streptococcus zooepidemicus'' and ''S. equisimilis'' are usually non-pathogenic | ||
| − | *Involved in [[ | + | *Involved in [[Peritonitis - Pathology#In pigs|peritonitis in pigs]], [[Pleural Cavity & Membranes Inflammatory - Pathology#Pyothorax (Thoracic empyema)|pyothorax]], [[Bones Inflammatory - Pathology#Osteomyelitis|osteomyelitis]], [[Stomatitis|catarrhal stomatitis]] |
*In infectious [[Joints Inflammatory - Pathology#In Sheep|arthritis of sheep]], [[Joints Inflammatory - Pathology#In Cattle|arthritis in calves]], [[Joints Inflammatory - Pathology#In Horses|arthritis in horses]] and [[Joints Inflammatory - Pathology#In Pigs|arthritis in pigs]] | *In infectious [[Joints Inflammatory - Pathology#In Sheep|arthritis of sheep]], [[Joints Inflammatory - Pathology#In Cattle|arthritis in calves]], [[Joints Inflammatory - Pathology#In Horses|arthritis in horses]] and [[Joints Inflammatory - Pathology#In Pigs|arthritis in pigs]] | ||
*Often commensals on mucous membranes of upper respiratory and lower urogenital tract | *Often commensals on mucous membranes of upper respiratory and lower urogenital tract | ||
Revision as of 13:31, 10 June 2010
Streptococcus species
Overview
- Cause suppurative infections in many different animals
- Cause abscess formation and septicaemia
- Cause mastitis, metritis, polyarthritis, meningitis
- Primary or secondary infections following viral infection
- Neonatal septicaemia related to maternal genital tract infection
- Haemolytic streptococci of Lancefield group C are common inhabitants of the equine nasopharynx
- Streptococcus zooepidemicus and S. equisimilis are usually non-pathogenic
- Involved in peritonitis in pigs, pyothorax, osteomyelitis, catarrhal stomatitis
- In infectious arthritis of sheep, arthritis in calves, arthritis in horses and arthritis in pigs
- Often commensals on mucous membranes of upper respiratory and lower urogenital tract
- Opportunistic infections
Characteristics
- Gram positive cocci forming chains
- Catalase negative, facultative anaerobes
- Fastitidious - require enriched media such as blood or serum
- Small haemolytic, translucent colonies, some mucoid
- Catalase negative
- Susceptible to desiccation
Identification
- Beta haemolysis (complete with clear zones surrounding colonies)
- Alpha haemolysis (partial with green zones surrounding colonies)
- Lancefield grouping - serology based on group-specific polysaccharide in cell wall
- Biochemical testing
Diagnosis
- Swabs of pus or exudate cultured on blood agar and MacConkey agar
- No growth on MacConkey except S. faecalis
- PCR, Lancefield grouping and biochemical tests
Pathogenesis and Pathogenicity
- Beta-haemolytic strains more pathogenic than alpha-haemolytic strains
- Virulence factors include streptolysins, hyaluronidase, DNase, streptokinase and proteases
- S. pyogenes, S. pneumoniae and some strains of S. equi have polysaccharide capsules which are antiphagocytic
- S. pyogenes and S. equi have antiphagocytic cell wall M proteins
Pages in category "Streptococcus species"
The following 10 pages are in this category, out of 10 total.