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Symptoms and Signs of How to Treat Staph (Staphylococcus) Infection

Doctor's Notes on Staph Infection(Staphylococcus) Infection

A Staph infection is an infection with Staphylococcus bacteria. Staph bacteria cause a number of different diseases and conditions, including superficial skin infections, toxic shock syndrome, food poisoning, septic arthritis, and bacterial infections of the bloodstream (septicemia). In some illnesses, the symptoms arise due to toxins secreted by the bacteria. In other cases, the symptoms are related to abscess formation and infection with the bacteria themselves.

Symptoms and signs of a Staph infection, therefore, vary widely and differ according to the type of illness that is present. Symptoms and signs can include skin rash, boils, redness, swelling, warmth, and drainage of pus from the skin. Other associated symptoms and signs can include fever, low blood pressure, nausea, vomiting, diarrhea, abdominal pain, and joint swelling and pain.

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Medically Reviewed on 3/20/2019

Staph Infection(Staphylococcus) Infection Symptoms

  • Most staph infections that are visible usually have a reddish, swollen, itchy, and/or tender area at the site of infection.
  • Often the site oozes pus or has some crusty covering with drainage.
  • Sites of infection can be small like a pimple on someone's face or even in the nose, a boil on an extremity, or large like a carbuncle.
  • Cellulitis (it most commonly appears on the legs) often shows redness and swelling of the involved area without pus, but impetigo shows a crusty weeping rash with an occasional blister.
  • Scalded skin syndrome shows extensive skin redness with bullae (fluid- or pus-filled blisters).
  • Infected catheters and other implanted devices usually show redness, pus, and tenderness at the skin entry site. Deep abscesses, pneumonia, osteomyelitis, and most other internal infections are only seen by X-ray and other imaging techniques or are not visible at all (for example, toxic shock, food poisoning) although nausea, vomiting, diarrhea and abdominal pain, chills, and fever may be present.

The appearances described above are only suggestive of staph infection; proof of infection depends on bacterial culture and subsequent identification of the infecting agent.

Staph Infection(Staphylococcus) Infection Causes

Almost any organ system can be infected by S. aureus. Most frequently, S. aureus strains first infect the skin and its structures (for example, sebaceous glands, hair follicles) or invade damaged skin (cuts, abrasions). Sometimes the infections are relatively limited (such as a sty, boil, furuncle, or carbuncle), but other times they may spread to other skin areas (causing cellulitis, folliculitis, or impetigo). Unfortunately, these bacteria can reach the bloodstream (bacteremia) and end up in many different body sites, causing infections (wound infections, abscesses, osteomyelitis, endocarditis, pneumonia) that may cause severe harm or even be fatal.

What Is a Staph Infection? Symptoms, Pictures Slideshow

What Is a Staph Infection? Symptoms, Pictures Slideshow

Staphylococcus is a type of bacteria that can cause many types of infections in your body. Commonly referred to as Staph (pronounced "staff"), it is common bacteria found on most people's skin, and often it does not cause disease. More than 30 types of Staphylococci bacteria cause infections, but the most common type of Staph infection is caused by Staphylococcus aureus. If the bacteria gains access to the body, either through a wound on the skin or via the respiratory tract, it can cause serious infections.


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.