Streptococcus anginosus group: Difference between revisions

Latest revision as of 18:25, 13 October 2020

Background

Microbiology

Catalase negative, variably hemolytic Gram-positive cocci within the viridans group streptococci
Contains Streptococcus anginosus, Streptococcus constellatus, and Streptococcus intermedius
- S. anginosus has two subspecies: S. anginosus subsp. anginosus and S. anginosus subsp. whileyi
- S. constellatus has three subspecies: S. constellatus subsp. constellatus, S. constellatus subsp. pharyngis, and S. constellatus subsp. viborgensis
Have a buttered popcorn smell on plate
Normal flora of oral cavity, throat, stool, and vagina
Identified using three rapid tests:
- Voges-Proskaur (VP) test for acetoin production
- Arginine hydrolysis
- Failure to ferment sorbitol

Clinical Manifestations

Tendency to form abscesses, unlike other streptococci, which can be polymicrobial with anaerobes and Enterobacterales
Infections can range in severity, and include pharyngitis, dental abscess, skin and soft tissue infection, pneumonia, empyema, lung abscess, brain abscess, liver abscess, and kidney abscess

Investigations

Presence of bacteremia without focus should prompt investigations to identify an occult abscess
The HANDOC score can assess need for echocardiography

Management

Typically treated with ceftriaxone or other third-generation cephalosporin pending susceptibilities
If found in an abscess, should be considered polymicrobial and treated with concomitant metronidazole
Clindamycin resistance is high, approximately 20-30%

@@ Line 1: / Line 1: @@
-== Background ==
+==Background==
-=== Microbiology ===
+===Microbiology===
-*Catalase [[Catalase::negative]], variably hemolytic [[Stain::Gram-positive]] [[Cellular shape::coccus|cocci]] within the [[viridans group streptococci]]
+*Catalase [[Catalase::negative]], variably hemolytic [[Stain::Gram-positive]] [[Shape::coccus|cocci]] within the [[viridans group streptococci]]
 *Contains ''Streptococcus anginosus'', ''Streptococcus constellatus'', and ''Streptococcus intermedius''
 **''S. anginosus'' has two subspecies: ''S. anginosus'' subsp. ''anginosus'' and ''S. anginosus'' subsp. ''whileyi''
@@ Line 14: / Line 14: @@
 **Failure to ferment sorbitol
-== Clinical Manifestations ==
+==Clinical Manifestations==
-* Tendency to form [[Abscess|abscesses]], unlike other [[streptococci]], which can be polymicrobial with [[anaerobes]] and [[Enterobacterales]]
+*Tendency to form [[Abscess|abscesses]], unlike other [[streptococci]], which can be polymicrobial with [[anaerobes]] and [[Enterobacterales]]
-* Infections can range in severity, and include [[pharyngitis]], [[dental abscess]], [[skin and soft tissue infection]], [[pneumonia]], [[empyema]], [[lung abscess]], [[brain abscess]], [[liver abscess]], and [[kidney abscess]]
+*Infections can range in severity, and include [[pharyngitis]], [[dental abscess]], [[skin and soft tissue infection]], [[pneumonia]], [[empyema]], [[lung abscess]], [[brain abscess]], [[liver abscess]], and [[kidney abscess]]
-== Investigations ==
+==Investigations==
-* Presence of bacteremia without focus should prompt investigations to identify an occult abscess
+*Presence of bacteremia without focus should prompt investigations to identify an occult abscess
+*The [[HANDOC score]] can assess need for [[echocardiography]]
-== Management ==
+==Management==
 *Typically treated with [[Is treated by::ceftriaxone]] or other third-generation [[Cephalosporins|cephalosporin]] pending susceptibilities
+*If found in an abscess, should be considered polymicrobial and treated with concomitant [[metronidazole]]
-*20-30% clindamycin resistance
+*Clindamycin resistance is high, approximately 20-30%
-*If found in an abscess, should be considered polymicrobial and treated with
 {{DISPLAYTITLE:''Streptococcus anginosus'' group}}