Phlegmon: Brief overview
- Definition: Bacterial inflammation of the skin that often spreads to connective tissue and muscles
- Causes and risks: Bacteria that usually enter via a wound. People with a weakened immune system are particularly at risk.
- Pathogen: Mostly Staphylococcus aureus, also Streptococcus pyogenes and other bacteria
- Symptoms: Dark or bluish redness, swelling, overheating, fluid accumulation (edema), pain, pus, fever
- Treatment: Antibiotics in all cases, additional surgical treatment in severe cases
- Prognosis: If not treated in time, the inflammation can spread further and become life-threatening in serious cases.
Phlegmon: Description
Phlegmon is a blurred, bacterial inflammation of the lower layers of the skin. In severe cases, deeper connective tissue and muscles are also affected. It usually develops around a wound or ulcer. As soft connective tissue is affected, doctors also refer to it as a soft tissue infection or soft tissue infection.
Phlegmon can occur in the following areas of the body, among others:
- Hands and tendon sheaths (e.g. hand phlegmon, V-phlegmon)
- Lower legs and feet
- Tongue, mouth (e.g. phlegmon of the floor of the mouth)
- Eye, eyelid and eye socket (orbitaphlegmons)
- Neck
Doctors generally differentiate between a limited phlegmon and a severe phlegmon. In the case of limited phlegmon, the inflammation extends to the lowest layer of skin (subcutis) at most. Severe phlegmon, on the other hand, is highly purulent and affects not only the skin but also connective tissue and/or muscles. In contrast to limited phlegmon, it must be treated surgically as well as with antibiotics.
The term cellulitis (not to be confused with cellulite – “orange peel skin”) is to be equated with phlegmon.
Phlegmon: symptoms
In the case of phlegmon, the infected skin area changes noticeably. It is characterized by the following symptoms
- Extensive, blurred, dark or bluish redness
- Doughy swelling
- Noticeably warm skin
- Accumulation of fluid (edema)
- Pressure or spontaneous pain
- Accumulation of pus (especially with severe phlegmon)
- Possibly black and yellow discoloration due to dead cells (in severe phlegmon)
Particularly in the case of severe phlegmon, the body also reacts with general symptoms such as
- fever
- Strong feeling of illness, fatigue
- High heart rate (tachycardia)
- Possibly shortness of breath and circulatory collapse (shock) if the infection spreads to the entire body
Further symptoms depend on the location of the phlegmon:
- Tongue phlegmon (glossitis phlegmonosa): Patients have severe pain when speaking and usually also when swallowing; an inflammatory swelling that spreads mainly towards the throat can constrict the airways and cause shortness of breath.
- Orbital phlegmon (orbital phlegmon): Patients are conspicuous by a protruding eye (exophthalmos), swollen eyelid, visual disturbances, conjunctival edema (chemosis) and restricted eye movements.
- Eyelid phlegmon: In contrast to orbital phlegmon, the inflammation remains limited to the eyelid. The eyelid is very swollen and reddened and it may no longer be possible to open the eye.
Phlegmons: causes and risk factors
Phlegmons are caused by bacteria, usually Staphylococcus aureus. Other bacteria such as group A streptococci (Streptococcus pyogenes) can also cause phlegmonous inflammation.
The pathogens penetrate the tissue particularly easily via large, open wounds. They then spread into the deep layers of the skin and cause inflammation there. The skin damage can have various causes, such as a cut, puncture or bite. However, smaller wounds (minor injuries) may also be sufficient entry points.
Phlegmons: Development of various phlegmons
Tendon sheath phlegmons are usually caused by harmless injuries such as a cut or puncture wound. The area swells and presses on blood vessels so that the tendon sheath is no longer supplied with nutrients. As a result, the tissue dies and provides an easy target for bacteria.
In V phlegmon, the inflammation runs along the tendon sheaths of the thumb and little finger. These are connected to each other at the wrist. This means that the inflammation can spread quickly and easily from one finger to the other via the wrist. If there is a phlegmon of the index, middle or ring finger, it remains limited to the affected finger, as there is no connection between these tendon sheaths.
Orbital phlegmon affects the soft tissue within the eye socket. It usually arises from an inflammation of the paranasal sinuses, which lie beneath the eye socket. The pathogens spread to the orbit via the wafer-thin bone lamella. Orbitaphlegmons are more rarely caused by a head injury. However, the bacteria can also enter the eye socket from another part of the body via the blood.
Eyelid phlegmons are caused by eyelid injuries or previous eyelid inflammations, such as a boil, eczema or sty.
Many patients ask themselves: “Is phlegmon contagious?”. Basically, people have numerous bacteria on their skin (including staphylococci) that can trigger phlegmon. These are not dangerous if the skin is intact and the immune system is stable. Nevertheless, you should protect yourself from direct contact with the wound secretion of a phlegmon by wearing gloves.
Phlegmon: examinations and diagnosis
If your skin is painful, swollen and red, consult a doctor. For minor symptoms, your family doctor is the first point of contact. However, it may be necessary for you to be admitted to hospital, for example if the phlegmon is on your face, if you have a fever or severe pain or if your physical condition is very poor.
The doctor in charge will first ask you in detail about your medical history (anamnesis). He will ask you the following questions, among others:
- How long have you had the symptoms?
- Have you been ill recently?
- Do you have any injuries or known (chronic) wounds?
- Are you suffering from an illness that weakens your immune system?
- How high is your fever?
If necessary and possible, your doctor will swab the wound or take a tissue sample (biopsy, usually as part of an operation that is necessary anyway) in order to determine the pathogens in the laboratory. This enables him to adapt the treatment to the causative bacteria. He usually also takes blood samples to determine inflammation values such as C-reactive protein (CRP) or white blood cells (leukocytes). If you have a fever, a blood sample can also be taken to look for bacteria (blood culture).
If you are suffering from an orbital aphlegmon, your doctor will also arrange for imaging of the eye socket and paranasal sinuses, such as a computer tomography (CT) scan. An ophthalmologist or ear, nose and throat specialist will also be consulted to look for the cause of the infection in this area in case of doubt and to monitor its further progress.
Differentiation from other soft tissue infections
Other soft tissue infections, such as erysipelas, (necrotizing) fasciitis or an abscess, are often difficult to distinguish from phlegmon. These are also bacterial inflammations of the skin. However, the correct diagnosis is important for the further treatment plan. This is why the doctor always makes sure to differentiate these diseases from phlegmon during the examination.
Erysipelas
Necrotizing fasciitis
Necrotizing fasciitis is a very serious, life-threatening bacterial infection, usually affecting the extremities (arms and legs). As a result, the skin, subcutaneous tissue and connective tissue sheaths (fascia) become inflamed. The muscles are also often affected. Streptococci are usually the cause. Their toxins cause tiny blood clots that block the fine blood vessels in the tissue. As a result, oxygen can no longer reach the affected region and the cells die (necrosis è necrotizing fasciitis). Patients have a fever and severe pain that cannot initially be explained by the visible skin symptoms.
Abscess
An abscess is an encapsulated cavity filled with pus in the deep layers of the skin, under a usually intact upper layer of skin. An abscess can also occur with a phlegmon, but is not typical.
Phlegmon: treatment
Phlegmon therapy consists of different stages, depending on the severity of the infection. As it is a bacterial infection, antibiotics help against phlegmon. They either kill the bacteria or prevent them from multiplying. The doctor will usually prescribe penicillins (e.g. flucloxacillin) or cephalosporins (e.g. cefazolin or cefuroxime). Clindamycin can also be used.
If the phlegmon is severe, it must also be treated surgically. The doctor removes dead tissue from the phlegmonous skin area and then rinses it (debridement). In some cases, open wound treatment is carried out. This means that the doctor does not close the wound after the operation. It is rinsed several times at intervals, drained and kept sterile with antiseptic dressings. In the case of an orbital phlegmon, surgical treatment of the paranasal sinuses may also be necessary.
What can you do yourself if you have a phlegmon?
Follow your doctor’s recommendations. He or she will discuss with you how long the antibiotic treatment should last and what you should bear in mind. It is also advisable to keep the affected area of the body
- to immobilize it,
- elevate it,
- to cool it.
Anti-inflammatory medication such as ibuprofen can help with accompanying symptoms such as pain. They relieve the pain, can inhibit the phlegmonous inflammation and thus support the healing process. Your doctor will prescribe the necessary active ingredients.
Phlegmon: course of the disease and prognosis
The inflammation also encourages blood clots (thrombosis). This can have life-threatening consequences, especially in the case of phlegmons in the facial area, if veins in the skull become blocked (sinus vein thrombosis). Meningitis or optic neuritis can also be the result of a phlegmon.
The bacteria can spread to the entire body via the blood and lymph vessels, especially if not treated in time. There is a risk of bacterial “blood poisoning” (sepsis), which is always life-threatening. Those affected are then cared for in an intensive care unit.
However, if those affected receive effective antibiotics immediately, phlegmon usually progresses well and improves within a few days.
