Following risk factors have been recognised for NSTIs - [10]
Immunosuppression
Diabetes
Chronic disease
Drugs e.g. steroids
Malnutrition
Age > 60
I.V. drug misuse
Peripheral vascular disease
Renal failure
Underlying malignancy
Obesity
Blunt or penetrating trauma
Surgery
Childbirth
CLASSIFICATION OF SOFT TISSUE INFECTIONS
ANATOMICAL CLASSIFICATION
1. Skin
Epidermis- Impetigo, folliculitis, furunculosis, carbunculosis.
Dermis- Cellulitis.
2.Subcutaneous tissue and Superficial fascia- necrotising fasciitis.
3. Fat, nerves, vessels, deep fascia- Automatic aponeurosis.
CLINICAL CLASSIFICATION[11]
Type I
Type I infections are the most common form of the disease. They are polymicrobial and wound tissue isolates identify on an average four different organisms. Causative microbes include a combination of Gram-positive cocci, Gram-negative rods, and anaerobes. These infections most frequently occur in the perineal and trunk areas in immunocompromised patients, particularly diabetics …show more content…
Group A streptococci can survive and replicate in macrophages, thereby escaping antibiotic therapy even in those tissues that remain well perfused and considered amenable to antibiotic penetration. Type II is the only NSTI associated with toxic shock syndrome. Type II is far less common than type I infection; however, this incidence is increasing, reflecting the rise in the incidence of community-acquired methicillin resistant S. aureus (MRSA) in some parts of the world. MRSA soft tissue infection has been reported particularly in i.v. drug abusers, athletes, and institutionalised groups. Type II NSTIs often occur in healthy, young, immunocompetent hosts, although frequently there is a history of recent trauma or