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Acute bacterial skin and skin structure infections Market (ABSSSIs) are common types of skin infections caused by bacteria. These infections can range from minor to severe depending on the causative bacteria and the individual’s health status. If not treated promptly with appropriate antibiotics, some of these infections can lead to serious complications. In this article, we will discuss the various types of ABSSSIs, causative organisms, risk factors, clinical presentation, diagnosis, and treatment.
Types of ABSSSIs
ABSSSIs are broadly classified into the following categories based on the depth of soft tissue involvement:
– Cellulitis: It is one of the most common types which involves the deep layers of the skin but not the underlying fascia or muscle. The skin appears red, swollen and painful.
– Abscess: It occurs when pus develops within the skin or soft tissue as a result of bacterial infection. The infected site appears swollen and fluctuant.
– Wound infections: These involve infected ulcers, burns, cuts or surgical wounds. The wound looks red, oozes pus and fails to heal.
– Major cutaneous abscess: It is a large abscess (typically >5cm) that often requires surgical drainage in addition to antibiotics.
– Infected diabetic foot ulcers: Chronic wounds on feet of diabetics that get secondarily infected can lead to severe soft tissue infections if not treated promptly.
– Infected burns: Burn injuries are more prone for secondary bacterial infections of the skin and soft tissues which can spread rapidly without treatment.
Causative organisms
The most common pathogens responsible for ABSSSIs include Staphylococcus aureus, Streptococcus pyogenes and various Gram-negative bacteria like Escherichia coli. Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as an important causative agent, especially in healthcare settings. The causative bacteria may differ based on the site of infection and individual risk factors.
Risk factors
Certain individual factors predispose to ABSSSIs:
– Diabetes mellitus: Poor sugar control impairs wound healing and defenses against infection.
– Obesity: Excess weight increases skin folds allowing bacteria to colonize and infect easily.
– IV drug use: Injection practices can introduce bacteria beneath the skin.
– Chronic illnesses: Diseases like cancer, liver disease, renal failure impact immunity.
– Old age: Elderly have reduced immune responses placing them at increased risk.
– Trauma/surgery: Lacerations, wounds, and surgical incisions provide entry points for bacteria.
– Smoking: It damages skin integrity and blood vessels, impairing wound healing.
Clinical features
The clinical manifestations of ABSSSIs depend on the type and extent of infection. Some key signs and symptoms include:
– Redness, swelling, pain, and tenderness over the infected area.
– Purulent drainage of pus from wounds or abscesses.
– Fever in severe or inadequately treated infections.
– lymph node swelling near the site of infection (Cellulitis).
– Rapidly progressive infection in immunocompromised individuals.
– Systemic symptoms like nausea, vomiting, diarrhea in severe cases with sepsis.
Detailed physical examination and probing can help identify abscesses requiring surgical drainage in addition to antibiotics.
Diagnosis
The diagnosis of ABSSSIs is generally based on clinical examination findings while evaluating risk factors. However, diagnostic tests may be required in certain scenarios:
– Wound/pus swabs or blood cultures: To isolate the causative pathogen and test for antimicrobial susceptibility.
– Imaging studies: Plain X-rays, ultrasound or MRI may help characterize abscesses, especially in poorly responsive infections.
– Biopsy: To diagnose infections mimicking skin cancers or deepseated lesions of uncertain etiology.
The diagnostic evaluation helps guide optimal antibiotic selection based on the likely pathogen and its resistance patterns. It also identifies conditions requiring surgical interventions.
Treatment
Prompt administration of appropriate antibiotics remains the mainstay of ABSSSI treatment to prevent complications:
– Mild-moderate infections: Oral antibiotics like cloxacillin, flucloxacillin or doxycycline started based on suspected pathogen and local resistance trends. 5-10 days of therapy is usually adequate.
– Severe infections: Parenteral (IV) antibiotics like vancomycin, linezolid, daptomycin or carbapenem started immediately for MRSA, mixed infections until clinical response observed. Duration depends on site and response but typically 5-14 days.
– Surgery: Incised, drained large abscesses to remove all necrotic tissues through which antibiotics penetrate poorly otherwise. This significantly improves cure rates.
– Diabetic foot infections: Urgent surgical debridement of wounds combined with targeted antibiotics and careful glucose control mandatory.
– Severe cases may require ICU admission, general supportive measures, dressings, and specialist referral based on site of infection and individual factors.
Proper hand hygiene, cleaning of minor cuts and boils, prompt medical attention and completion of recommended antibiotic course helps prevent recurrences and complications of ABSSSIs. Vaccination against Streptococcus also offers some protection.
Conclusion
In conclusion, ABSSSIs are common bacterial skin infections that vary from mild to life-threatening based on causative organism and host factors. Prompt diagnosis and targeted antibiotic therapy guided by culture/susceptibility testing remains the mainstay of management. Surgery plays an adjunct role in severe infections requiring debridement. Adherence to preventive measures and treatment compliance helps contain the growing threat of antibiotic resistance in community acquired skin infections.
