Streptococcus anginosus group ( Streptococcus millieri group )
|Next review: 04/11/2023|
|Approved By: Trust Clinical Guidelines Group|
|Copyright© Leeds Teaching Hospitals NHS Trust 2020|
This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
Department of Microbiology Bacteraemia Guideline
Streptococcus anginosus group (Streptococcus millieri group)
- About Streptococcus Anginosus group
- Clinical differential diagnosis
- Antimicrobial susceptibilities
- Antimicrobial treatment
- Supplementary investigations
Quick reference guide to the management of bacteraemia with
Streptococcus anginosus group
This document provides guidelines for doctors on the management of patients with confirmed bacteraemias (blood cultures). This document is supplementary to, and should be used in conjunction with, the antimicrobial guidelines.
Streptococcus anginosus group (Streoptococcus millinery group)
The aim of this guideline is to:
- Provide education to junior microbiology registrars
- Support communication of Gram stain results from microbiologists to ward doctors
- Support ward doctors in treating and investigating bacteraemic patients
The blood culture process: Timings of culture, identification, susceptibility tests and clinical liaison.
How to use this guideline: This guideline should be used to help in the management of patients with a confirmed bacteraemia. The guideline should be used to support interaction with specialist advice e.g. Microbiology.
- The “anginosus group” which is also known as the “Streptococcus millieri group” belongs among the Viridans streptococci and corresponds to three species-S. intremidius, S. constellatus, S .anginosus.
- These organisms are part of the oropharyngeal flora and they are also found in the gastrointestinal tract and in the vagina.
- Can cause invasive pyogenic infections, which usually differentiates them from other viridans streptococci3.
The differential diagnosis of bacteraemia with S. anginosus group includes:
- Abdominal infections (liver abscesses, peritonitis, appendicitis, cholangitis)
- Pelvic infections
- Thoracic infections (Lung abscesses, empyema)
- Brain Abscesses
- Skin and Soft tissue infections (cellulitis, subcutaneous abscesses)
- Dental infections
- Other infections ( osteomyelitis, septic arthritis, wound infections)
- Members of S. anginosus group are largely susceptible to beta-lactam agents. Resistance to penicillin is rare4,5
- Vancomycin is an appropriate alternative agent if the patient has allergy to penicillin
- Resistance to Clindamycin and Erythromycin has been described and appears to be emerging among S. anginosus group5
- Resistance to quinolones tends to develop easily and therefore are not appropriate first line agents6
- Most strains of anginosus group are resistant to aminoglycosides, however synergy with b-lactam agent usually can be demonstrated7
- Antibiotic therapy should always be reviewed with speciation of the bacteria, and with results of sensitivity tests
History of the following are important to determine appropriate antimicrobial therapy
- Source of infection
- Allergy status
The table below outlines some of the common infections associated with each of the clinical syndromes.
Discuss with microbiology
Infected Parapneumonic Effusions and Empyema
Consider further investigations as appropriate to source of infection, please see relevant guidelines.
Surgical drainage of an abscess is usually indicated as an adjunctive therapy.
|Target patient group:|
|Target professional group(s):||Secondary Care Doctors
- BNF Link
- EMC Link
- Claridge JE et al. Streptococcus intermidius, Streptococcus constellatus and Streptococcus anginosus are of different clinical importance and are not equally associated with abscess. Clin Infect Dis.2001;32:1511-1515
- Tracy M et al. Antibiotics susceptibilities of genetically characterizes Streptococcus millieri group strains. Antimicrob Agents Chemother.2001;45:1511-1514
- Trends in Antimicrobial Resistance in England and Wales 2004-2005. HPA
- Yamamoto N et al. In vitro activity of sitafloxacin compared with several fluoroquinolones against Streptococcus anginosus and Streptococcus constellatus. Int J Antimicrob Agents.2006;27(2):171
- Stelzmueller I et al. Relevance of group Milleri streptococci in thoracic surgery: a clinical update. Am Surg.2007;73(5):492
Trust Clinical Guidelines Group
LHP version 1.0
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