The SSTI medical abbreviation stands for skin and soft tissue infection, which is an umbrella label for infections of the skin and the layers just under it, such as fat, connective tissue and the covering of muscles. Cellulitis and skin abscesses are the most familiar examples.
SSTI is a grouping term, much like saying chest infection, so a note may use it before or alongside a more exact diagnosis. You will see it in emergency department notes, urgent care visits, wound care records and hospital problem lists. This page explains what conditions fall under it, how a typical note reads and which nearby terms point to something more serious.
At a glance
Stands for
Skin and soft tissue infectionPlural
SSTIsCommon examples
Cellulitis, abscess, impetigo, erysipelas, infected woundsWhere you see it
ED and urgent care notes, problem lists, wound care recordsUsual germs
Staph and strep bacteria, including MRSADo not confuse with
STI (sexually transmitted infection) and NSTI, a severe deep infectionSpecialty
Emergency medicine, infectious disease, surgery
What the SSTI medical abbreviation includes
Skin and soft tissue infections range from mild problems treated at home to serious infections that need surgery. Most are caused by bacteria entering through a break in the skin, such as a cut, bite, insect sting, surgical wound or cracked dry skin.
Typical signs are redness, warmth, swelling and pain over an area of skin. Some people also have fever or feel unwell. Doctors often draw a line around the red area with a skin marker so the team can see whether it spreads or shrinks over the next day.
Conditions grouped under SSTI
| Condition | What it is |
|---|---|
| Cellulitis | Spreading infection of the deeper skin and fat |
| Abscess | A pocket of pus under the skin |
| Erysipelas | A more surface infection with sharp, raised edges |
| Impetigo | A surface skin infection with honey-colored crusts, common in children |
| Folliculitis or furuncle | Infection of a hair follicle, sometimes called a boil |
| Wound infection | Infection of a cut, bite or surgical incision |
Doctors may also split SSTIs into purulent, meaning with pus, and nonpurulent, which helps guide treatment choices.
Reading an SSTI line in a real note
Emergency notes pack a lot into the assessment and plan. Here is one broken down.
| Note fragment | Translation |
|---|---|
| A/P | Assessment and plan |
| SSTI L forearm | Skin and soft tissue infection of the left forearm |
| cellulitis with small abscess | Spreading skin infection plus a pocket of pus |
| I&D | Incision and drainage, opening the abscess to drain it |
| in ED | Done in the emergency department |
On a problem list: "Recurrent SSTI, MRSA on prior culture." Anyone reading this later learns the person has had several skin infections and that one grew methicillin-resistant staph, which can change antibiotic choices.
Warning terms that signal a deeper infection
A small number of soft tissue infections spread fast and deep. Notes may use words such as necrotizing, crepitus, which means a crackling feel under the skin from gas, or pain out of proportion to exam. These point toward a necrotizing soft tissue infection, written NSTI, which is a surgical emergency.
Other words that raise concern include spreading redness despite treatment, signs of SIRS such as fast heart rate and fever, or infection near a joint or prosthetic device. Clinicians look for these clues when deciding how urgently to act.
SSTI versus STI
The letters differ by just one S, but the meanings are unrelated. STI means sexually transmitted infection. SSTI refers to infection of the skin and the tissue beneath it, anywhere on the body. A careless typo can change a note's meaning entirely, so writers should double-check, and readers should look at the rest of the line for clues such as a body site or a word like cellulitis.
Other infection and diagnosis terms live in the condition abbreviations index.
Things to clarify about a red, swollen area
- Is this cellulitis, an abscess, or both?
- Was a culture taken, and will the result change the plan?
- What changes in the redness or swelling mean I should come back?
- How should I care for the wound or drained area at home?
Skin infections can look alike but need different care. A doctor, nurse practitioner or wound care nurse should look at any red, warm or painful area of skin and say how it should be cared for.
Frequently asked questions
What does SSTI mean in medical terms?
It is short for skin and soft tissue infection. It covers infections of the skin and the tissue just beneath it, such as cellulitis, abscesses and infected wounds.
Is cellulitis an SSTI?
Yes. Cellulitis is one of the most common skin and soft tissue infections. A note may use SSTI as the broad label and cellulitis as the exact diagnosis.
Is SSTI the same as STI?
No. STI means sexually transmitted infection. SSTI means an infection of the skin and soft tissue, so one added letter turns it into a different topic altogether.
What causes most SSTIs?
Most are caused by staph or strep bacteria that enter through a break in the skin. Some are caused by MRSA, a staph germ resistant to certain antibiotics.
How does NSTI relate to SSTI?
NSTI means necrotizing soft tissue infection, a rare but severe type that destroys tissue and spreads fast. SSTI is the broad group, while NSTI is a serious subset that usually needs urgent surgery.