The diagnosis of primary or idiopathic NF may be challenging because it occurs in the absence of a known causative factor or portal of entry for bacteria [11
]. In most cases, NF occurs as a result of a known etiology, and classified as secondary NF. Bacterial entry occurs as a result of some precipitating events such as laceration, cut, abrasion, contusion, burn, bite, subcutaneous injection, or operative incision, that cause a break in the epidermidis. Secondary NF may also occur as a result of an occult infection such as a perforated viscus or as a complication of peri-rectal abscess or infected Bartholin cysts [16
Primary or idiopathic NF, however, occurs in the absence of a known or identifiable etiologic factor. The underlying pathogenesis of idiopathic NF is still unknown. In terms of early diagnosis and management, it is important to consider that idiopathic NF exists, and that it is a distinct clinical entity.
The following symptoms of NF were compiled from the Center for Disease Control and Prevention and the National Necrotizing Fasciitis Foundation:
Early symptoms (usually within 24 hours):
1. Usually a minor trauma or other skin opening has occurred (the wound does not necessarily appear infected)
2. Some pain in the general area of the injury is present. Not necessarily at the site of the injury but in the same region or limb of the body
3. The pain is usually disproportionate to the injury and may start as something akin to a muscle pull, but becomes more and more painful
4. Flu like symptoms begin to occur, such as diarrhea, nausea, fever, confusion, dizziness, weakness, and general malaise
6. The biggest symptom is all of these symptoms combined. In general you will probably feel worse than you've ever felt and not understand why.
Advanced symptoms (usually within 3–4 days):
1. The limb, or area of body experiencing pain begins to swell, and may show a purplish rash
2. The limb may begin to have large, dark marks, that will become blisters filled with blackish fluid
3. The wound may actually begin to appear necrotic with a bluish, white, or dark, mottled, flaky appearance.
Critical symptoms (usually within 4–5 days):
1. Blood pressure will drop severely
2. The body begins to go into septic shock from the toxins the bacteria are giving off
3. Unconsciousness will occur as the body becomes too weak to fight off this infection.
DM is the leading predisposing factor in both idiopathic and secondary NF in our patient population. The mechanisms that has been suggested how DM could cause susceptibility to NF are: a) The peripheral sensory polyneuropathy experienced by diabetics may increase susceptibility to minor trauma. b) tissue hypoxia caused by diabetic vascular disease and the underlying immunodeficiency [17
]. Even though there is substantial evidence indicating an important role of DM in the etiology of NF, its role as a predisposing factor for increased death rate is controversial. Some reports failed to show a significant relationship between mortality and DM in NF [9
]. Interestingly, however, DM was determined as a significant factor associated with mortality in multivariate analysis in our study.
Immuno-competence has been claimed to be an important factor in the etiopathogenesis of NF [19
]. Sudarsky et al reported that 91% of their patients with NF had some associated immunodeficiency [20
]. These predisposing conditions are mainly DM, alcoholism, end-stage renal disease, malignancy, chemotherapy, malnutrition, corticosteroid use, multitrauma and the peripartum period [8