Skin and soft tissue infections are related to the invasion of microorganisms into the skin and underlying soft tissues. Patients with skin and soft tissue infections typically present with redness, warmth, swelling, and pain at the affected site. Systemic features of the infection may follow, with the intensity reflecting the degree of infection. Symptoms commonly affect the lower limbs.
Definition and classification of skin and soft tissue infections
Skin and soft tissue infections encompass infections of the skin, subcutaneous tissue, connective tissue, and muscle, presenting with a range of clinical symptoms. These symptoms range from simple cellulitis to rapidly progressing necrotizing fasciitis.
Skin and soft tissue infections can be classified into the following types:
- Uncomplicated skin and soft tissue infections, including cellulitis, folliculitis, impetigo, simple abscesses, and minor wound infections. These infections pose little risk to the patient’s life and limbs.
- Complicated skin and soft tissue infections may involve deeper tissue invasion and often require surgical intervention. Treatment response is often complicated due to underlying comorbidities. In this category, infections include complicated abscesses, infected burns, infected ulcers, diabetic foot infections, deep infections, etc. These infections commonly affect the limbs and can be life-threatening.
- Necrotizing fasciitis is a rapidly progressive, rapidly spreading, deep tissue infection that is associated with secondary necrosis of the subcutaneous tissues. The inflammatory condition of the deep connective tissue causes thrombosis of the dermal vessels, resulting in secondary necrosis of the subcutaneous and skin tissues. Those at high risk are individuals with open wounds exposed to dirt or bacteria.
Signs of skin and soft tissue infections.
Causes of skin and soft tissue infections
The causes of skin and soft tissue infections include old age, heart, lung or liver disease, diabetes, debilitation, weakened immune system, obesity, peripheral artery disease or leukopenia, and injury.
Infections often occur after trauma, surgical wounds, etc. Some characteristics of skin and soft tissue infections caused by bacteria are as follows:
Staphylococcus aureus and anaerobic Streptococcus cause abscesses with typical features such as purulent discharge with surrounding granules, patient experiences pain, swelling, stiffness, and if severe, can cause skin necrosis.
Patients infected with skin and soft tissue infections due to animal bites, other objects such as Bacteroides, Bartonella henselae, Capnocytophaga canimorsus, Eikenella corrodens, Pasteurella multocida, Peptostreptococcus, S. aureus… Infection usually occurs within 8 to 12 hours after an animal bite. Human bites can also transmit herpes…
Clostridium-induced muscle necrosis, usually C-perfringens, C-septicum: usually occurs after trauma or spontaneously. Patients often experience severe pain at the site of injury, followed by skin changes, stiffness, and blistering… In severe cases, patients may have symptoms of fever, hypotension, and tachycardia.
Cellulitis caused by Haemophilus influenzae, S. aureus: erysipelas usually appears on the face, ears, or lower limbs, and the affected skin is clearly inflamed. Cellulitis usually occurs in areas where the skin is damaged…
Deep folliculitis caused by S. aureus infection: Patients often experience pain, swelling, and stiffness, with features of systemic infection, and the subcutaneous tissue is thicker in the neck and back…
Impetigo caused by Beta-hemolytic streptococci, S. aureus: This disease often occurs in children and infants, affecting the nose, mouth, or extremities, and can also spread to lymph nodes, bones, and joints…
Necrotizing fasciitis is a widespread infection of subcutaneous tissue that affects the genitals, pelvis, or lower limbs…
Skin and soft tissue infections appear in many places.
How is skin and soft tissue infection diagnosed?
Clinical symptoms
Patients with skin and soft tissue infections typically present with redness, warmth, swelling, and pain at the site of injury. Systemic manifestations of infection may follow, and their severity reflects the degree of infection. The disease symptoms often affect the lower extremities.
Characteristic features of superficial infections include induration and cellulitis.
Patients with necrotizing fasciitis may experience pain disproportionate to physical signs. Additionally, patients with advancing infections may develop cutaneous anesthesia, hemorrhage or severe changes, and crepitus indicating gas in soft tissues.
The presence of excessive edema and bullae helps differentiate necrotizing fasciitis from non-necrotizing infections.
Ancillary tests
Patients with skin and soft tissue infections often have an elevated white blood cell count, particularly neutrophils. The erythrocyte sedimentation rate and C-reactive protein levels are also elevated.
Blood cultures should be obtained in these patients to identify possible bacteria that may yield a positive result. Additionally, patients may have fresh specimens or cultures grown from pus to identify bacteria, which would guide antibiotic therapy.
Patients may undergo ultrasonography, CT, or MRI to assess inflammatory changes, subcutaneous emphysema, soft tissue, and muscle.
Very dangerous untreated skin and soft tissue infections.
Treatment protocols for skin and soft tissue infections:
The treatment of skin and soft tissue infections is determined by the severity and location of the infection, as well as the patient’s level of consciousness.
Antibiotic treatment for skin and soft tissue infections:
If there are no antibiotics available, the following treatments can be used:
- For patients without systemic signs and no accompanying pathology, use oral antibiotics such as Erythromycin, Cephalexin, Augmentin, Clindamycin.
- For patients who may have systemic signs and accompanying diseases, use Nafcillin or Oxacillin with a dose of 1-2g/4h/day. Alternatively, give the patient clindamycin at a dose of 600mg/dose, every 8 hours, or Vancomycin at a dose of 30mg/kg/day divided into 2 doses. If there is suspicion of Meticillin-resistant Staphylococcus aureus (MRSA) infection, use Vancomycin, Linezolid, or Daptomycin.
- If the patient has sepsis, systemic symptoms, or life-threatening infection syndrome, use combination antibiotics. Alternatively, the patient can be given a combination of Meropenem, Ertapenem, or Imipenem.
- After 48-72 hours, evaluate the patient’s response and adjust the antibiotic regimen accordingly.
In addition, supportive pain relief treatment for infected patients can be done using Paracetamol, Codeine, Tramadol, or non-steroidal anti-inflammatory drugs (NSAIDs) if necessary.
At the same time, it is necessary to care for the infection site, change the wound dressing, and perform pus surgery if necessary.
During the treatment process, it is important to monitor the patient’s vital signs, systemic and local symptoms, to be able to timely adjust the treatment. Patients should be regularly monitored for liver and kidney function and blood indices.
We hope this article will help readers better understand the appropriate detection and treatment of skin and soft tissue infections.
Johnny Jacks was born in 1985 in Texas, USA. He is the founder of Good Health Plan and is passionate about helping people improve their health and physical well-being. With over a decade of experience working in the healthcare industry, he currently works at Goodheathplan.com – a blog that shares knowledge on beauty and health.