Diagnosing Flesh-Eating Disease

Flesh-eating disease, or necrotizing fasciitis, is a rapidly-spreading infection caused by Streptococcus group A bacteria, usually of the species Streptococcus pyogenes. Flesh-eating disease causes tissue death, or necrosis, and spreads to other parts of the body rapidly. The infection usually occurs through a small wound in the skin. Strep group A bacteria are commonly found, even on some healthy people, and they also cause a variety of milder infections, such as strep throat. Necrotizing fasciitis is a rare type of strep infection. If left untreated, this infection can spread to the bloodstream and internal organs. Necrotizing fasciits has a high mortality rate of about 25 percent.

Few infections spread as quickly as necrotizing fasciitis, so the disease can often be diagnosed just from the timeline of the symptoms and the rate of the spread of the infection. Within the first 24 hours of the infection, the infected wound may become extremely painful. The pain may start out as a mild soreness, but it generally increases in severity very quickly. The pain is often described as being disproportionate to the appearance of the wound; the wound may look small and be more painful than it looks. Other symptoms, such as fever and flu-like symptoms, are often present, so the patient may feel much worse than they would expect from the appearance of the wound. The wound may start to appear inflamed and infected within hours or days. The infected area may appear red or purple and start to blister or develop blackened areas where the tissue has become gangrenous and died. Clinical examination of the infected area combined with the accounts of the rapid spread of the infection often leaves no room for doubt that the infection is a case of flesh-eating disease.

Another diagnostic tool, besides clinical examination of the infection, is to test the infected tissue for Streptococcus bacteria. Medical imaging may also be used to see the extent of the infection and determine whether the infection has spread internally. However, it is important to start antibiotic treatment as soon as possible in cases of flesh-eating disease, so if the clinical presentation of the infection makes it apparent that it is a case of flesh-eating disease, surgery may be performed or IV antibiotics may be given before the cause of the infection is known through lab work.