Home > Microbiology & infectious diseases > Staph aureus

Microbiology & infectious diseases

Gram positive bacteria

Staph aureus

Author: Christopher S. Hale, M.D.

Last author update: 1 August 2013

Last staff update: 1 October 2020

Copyright: 2002-2024, PathologyOutlines.com, Inc.

PubMed Search: Staphylococcus aureus[title]

Page views in 2024 to date: 137

Table of Contents

Cite this page: Hale C. Staph aureus. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/microbiologystaphaureus.html. Accessed December 4th, 2024.

Definition / general

Gram stain: positive
Morphology: cocci in clusters
Facultative anaerobe
Part of normal flora of skin, mucus membranes, nasal passages

Terminology

Greek "Staphyle" (grape) + coccus, referring to grape cluster-like morphology on Gram stain

Sites

Staphylococcal food poisoning
Staphylococcal scalded skin syndrome
Skin and soft tissue infections
Septic arthritis
Endocarditis
Bacteremia
Any body site may be infected

Laboratory

Culture conditions:
- BAP (non-contaminated sites), colistin nalidixic acid agar (contaminated sites) or mannitol-salt agar
- Chromogenic agars (J Clin Microbiol 2003;41:5695)
- 34 - 37°C
Gram positive
Catalase positive
Coagulase positive (slide or tube test)
Mannitol fermenter
Novobiocin sensitive (S. saprophyticus is novobiocin resistant)

Treatment

Penicillin resistance widespread, treatment depends on local susceptibility patterns, infection site, clinical context
MRSA: methicillin-resistant Staphylococcus aureus; resistant to beta-lactam antibiotics
Community acquired MRSA: use macrolides, clindamycin, cotrimoxazole
Multiresistant MRSA: use vancomycin (Intern Med J 2005;35:S97)
Infectious Disease Society of America MRSA treatment recommendations

Clinical images

Images hosted on other servers: