Necrotising Fasciitis
Pathogenesis This is an acute infection of the deep soft tissues overlying the muscle, involving the facial planes and subcutaneous fat. These are infections that lead to necrosis and tissue destruction. They are often rapidly spreading and associated with toxic/septic patients. In general, there are 2 classes of organisms causing necrotising infections: Type I: Mixed infection, containing at least 1 anaerobe AND one anaerobic streptococci AND one gram negative.Type II: Monobiotic – often Group A Strep, due to it possessing the M protein, an antiphagocytic protein. Known risk factors include: DiabetesDrug useObesity Necrotising fasciitis can spread from various areas an niduses of infection Ludwigs Angina – Necrotising Fascitis of mandibular and sublingual spaces, stemming from dental infection or instrumentationFourniers Gangrene – Necrotising infection of the male perineum, often stemming from a perianal abscess Presentation Variable depending on patient population. This author has seen patients present for entirely different reasons (in this case, a very mechanical, non injurious fall), and only upon careful general examination were found to have necrotising fasciitis In general, there is minimal or minor skin findings in the early stage of the illness. Erythema is common, with warmth, looking much like cellulitis or a pressure are. It will be intensely painful however As the disease progresses there will be frank necrosis of the skin, with redness becoming black, bullae may form. Occasionally the area will become numb, signifying necrosis of the underlying nerve fibres Subcutaneous emphysema can be present if there is a mixed organism growth. These patient are often septic
