Necrotising fasciitis (NF), commonly known as flesh-eating disease, is a rare infection of the deeper layers of skin and subcutaneous tissues which easily spreads across the fascial plane within the subcutaneous tissue. Necrotising fasciitis is a severe disease of sudden onset that progresses rapidly.
It occurs more often in the immunocompromised due to conditions such as diabetes or cancer. The disease is classified into four types, depending on the infecting organism. The most common type is caused by a mixture of bacterial types, and commonly occurs at sites of surgery or trauma, usually in the abdominal or perineal areas and accounts for 55-75% of cases. Since 2001, a form of monomicrobial necrotizing fasciitis, which is particularly difficult to treat has been observed with increasing frequency caused by methicillin-resistant Staphylococcus aureus (MRSA).
It is usually treated with surgical debridement or amputation, and intravenous antibiotics. Delays in surgery are associated with higher mortality.
There are 0.04 cases per 1000 per year in the US. The most consistent feature of necrotising fasciitis was first described in 1952 as necrosis of the subcutaneous tissue and fascia with relative sparing of the underlying muscle.
Signs and symptoms
People usually complain of intense pain that may seem excessive given the external appearance of the skin. People initially have signs of inflammation, fever and a fast heart rate. With progression of the disease, often within hours, tissue becomes progressively swollen, the skin becomes discolored and develops blisters. Crepitus may be present and there may be a discharge of fluid, said to resemble “dishwater”. Diarrhea and vomiting are also common symptoms.
In the early stages, signs of inflammation may not be apparent if the bacteria are deep within the tissue. If they are not deep, signs of inflammation, such as redness and swollen or hot skin, develop very quickly. The skin color may progress to violet, and blisters may form, with subsequent necrosis (death) of the subcutaneous tissues.
Furthermore, people with necrotizing fasciitis typically have a fever and appear sick. Mortality rates are as high as 73 percent if left untreated. Without surgery and medical assistance, such as antibiotics, the infection will rapidly progress and will eventually lead to death.