This section was reviewed by Dr. Catherine Bergeret-Galley , a specialist in plastic, reconstructive, and aesthetic surgery, and president of the SNCPRE. The reviewer is responsible for the section's content within her specialty; articles are constantly evolving and not all are individually reviewed.
An infection of a surgical scar may be suspected if the area becomes redder, warmer, more painful, or begins to ooze. However, no single sign can definitively confirm the diagnosis. The wound's progression, the patient's overall health, the type of surgery performed, and the possible presence of an implant or drain must all be assessed together.
This guide helps recognize concerning changes, avoid actions that could complicate the assessment, and contact the appropriate team. It complements discharge instructions and our post-operative dressing guide . It does not identify the specific pathogen or determine the appropriate treatment.
Infection of a surgical scar: what does this entail?
The skin is not always the only area affected.
A surgical site infection can remain superficial or involve deeper tissues. It can also affect the surgical area around implanted hardware. Therefore, the visible appearance does not always reflect the entire situation. A small incision may warrant evaluation if pain or the patient's overall condition worsens.
A diagnosis cannot be made based on a single photograph.
A photograph may show color, opening, or discharge, but it does not provide information about heat, odor, depth, pain, or breathing. It can supplement an exchange if requested by the service through a secure channel, but it does not replace an interview or examination.
What changes in the scar should raise concern?
- Redness that progresses or spreads around the wound.
- Localized heat associated with new or increasing pain.
- A swelling that increases or becomes tense.
- A cloudy, thick, colored, or foul-smelling liquid.
- Edges that pull apart or a wound that opens.
- Unusual or recurring bleeding.
These signs do not all prove an infection, but they warrant contacting the team. Pain can also have other postoperative causes. Our guide on pain after surgery explains how to describe its location, progression, and associated symptoms.
How to distinguish between healing and abnormal development?
Observe the trajectory rather than a timeline
Slight tenderness, swelling, or discoloration may accompany the healing process, but there is no universal timeline that applies to all procedures. Compare the wound to its initial appearance and to the guidelines provided by the department. A sudden worsening or change in the wound is more important than a theoretical date.
Take into account all skin colors
Redness may be less noticeable on brown or dark skin. Also look for any change from the usual color, a warmer area, swelling, increased sensitivity, or discharge. Don't let a photo that appears "not very red" delay seeking medical advice if other signs change.
Does a normal temperature rule out infection?
No. Some postoperative infections can occur without a measured fever. A diagnostic study showed that temperature alone was inaccurate in detecting certain infections after elective surgery. Conversely, a high temperature is not sufficient to prove that the wound is infected.
Therefore, also monitor chills, discomfort, alertness, breathing, pain, urination, fluid tolerance, and overall recovery. A person who feels significantly worse warrants a consultation even if the thermometer shows their usual reading.
What should be done if an infection is suspected?
Contact the team that is familiar with the procedure.
Use the number on your discharge letter or in the file provided by the hospital. The surgical team is familiar with the procedure, the materials used, the closure method, the risks associated with the intervention, and the initial appearance. If they cannot be reached, follow the instructions on your documents or contact a doctor without delaying any necessary assessment.
Prepare a factual description
- The name and date of the operation.
- The moment when the appearance of the wound changed.
- The evolution of pain, swelling and discharge.
- The presence of a drain, wires, staples or an implant.
- The temperature with the time and the method of measurement.
- Other symptoms and treatments taken.
A clear timeline helps the professional decide on the next steps. The pre-operation preparation checklist reminds them of the importance of keeping the department's contact information, the prescription, and the report readily available.
What actions should be avoided before receiving advice?
Do not manipulate the wound to "test" it.
Do not squeeze the scar to force out fluid, do not pick at a scab, and do not try to bring the edges together. Do not remove a dressing or device if instructions say to leave it in place. Do not cut any visible stitches and never disconnect a drain.
Do not apply a product randomly.
Do not use any leftover product, cream, powder, essential oil, or homemade preparation. Applying these may irritate the tissues, contaminate the area, or alter the appearance being examined. Do not change any prescribed treatment without consulting the team.
Bathing and immersion are not suitable for cleaning a suspicious wound. The information sheet on bathing after surgery explains why authorization depends on the closure and actual condition of the scar.
How to limit manipulations while waiting for the opinion?
Wash your hands before and after any explicitly authorized procedure. Keep the dressing clean according to the instructions received and avoid rubbing. If the dressing is saturated, displaced, or soiled, ask the ward staff for advice rather than attempting to change it yourself.
Do not apply compression to a swollen area and do not apply a cold compress directly to the wound. Swelling can have several causes and should be documented. The guide on postoperative edema outlines the associated signs that determine the urgency of the situation.
When should you seek urgent help?
For rapid local worsening
A wound that opens, pain that increases significantly, heavy drainage, spreading redness, or tense swelling requires prompt medical attention from the team. Do not wait for a fever or a predetermined duration. If the situation cannot be assessed over the phone, follow the professional's instructions.
For general signs of severity
Call 15 or 112 if you experience confusion, loss of consciousness, significant difficulty breathing, chest pain, mottled skin, a purplish rash that does not blanch when pressed, or a rapid deterioration in your general condition. Recent surgery is a risk factor that should be reported to the dispatcher.
Who requires increased vigilance?
A frail, immunocompromised person, someone with certain chronic illnesses, malnutrition, or an implanted device may present with less obvious signs and deteriorate more rapidly. An intervention performed in an already infectious context or as an emergency also alters the assessment.
After abdominal surgery, abdominal wall pain and swelling can be difficult to interpret without an examination. The landmarks in the patient's file on post-abdominoplasty scars illustrate why the progression of these changes must always be considered in the context of the procedure performed.
Tobacco use is among the identified risk factors: it is associated with an increased risk of wound healing complications. The recommendations regarding smoking before and after surgery , and the cessation periods mentioned therein, are detailed separately.
What can the healthcare team decide?
The healthcare professional may request a wound examination, look for general signs, check an implant or drain, and decide if a biopsy or other test is necessary. The course of action depends on the depth, location, procedure, and the patient's condition.
This assessment explains why a solution used in a previous procedure should not be automatically repeated. The correct goal at home is not to self-treat, but to provide reliable information and obtain appropriate advice.
F.A.Q
Does a discharge always mean infection?
No. Its color, odor, quantity, evolution, and other signs matter. However, a new, cloudy, or foul-smelling discharge should be reported.
Can surveillance be done using only photos?
No. Photos can document progress but do not replace the general condition, heat, pain, smell, or examination.
Should we wait for the temperature to rise?
No. A normal temperature does not rule out infection. A changing wound or a deteriorating general condition warrants a consultation without waiting for a specific temperature reading.
Verified sources
- Centers for Disease Control and Prevention, Surgical Site Infection Basics
- NICE, Prevention and treatment of surgical site infections
- Guy's and St Thomas' NHS, Surgical Wounds and Infection Prevention
- French National Authority for Health, Management of sepsis prior to emergency room visits
- World Health Organization, Prevention of surgical site infections
- University Hospitals Plymouth NHS, Surgical Wound Care
- Diagnostic study, temperature and detection of postoperative infection
Editorial note: General information article verified on July 16, 2026. Any suspicion of infection requires professional advice; exit guidelines take precedence over this guide.
