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CHAPTER 21

Necrotising Fasciitis

Jacob N. Legbo
Emmanuel A. Ameh

Introduction
1
The term necrotising fasciitis (NF) was first coined in 1952 by Wilson
to describe a rapidly progressive inflammation and necrosis of subcu-
taneous tissues and the deep layer of superficial fascia with sparing of
the deep fascia and muscle. It had previously been described variously
as haemolytic gangrene, acute streptococcal gangrene, gangrenous
erysipelas, necrotising erysipelas, suppurative fasciitis, and hospital
2,3
gangrene, among other names. However, the term necrotising fas-
ciitis is now used in a generic sense to include all diffuse necrotising
soft tissue infections except gas gangrene (clostridial myonecrosis).
4
Diffuse necrotising soft tissue infections include classic gas gangrene,
Meleney’s haemolytic streptococcal gangrene, necrotising fasciitis as
described by Wilson, and the gram-negative synergistic necrotising
cellulitis of Stone. Generally, one condition cannot be distinguished
from another at the time of diagnosis. Today, the orofacial form of NF is
5
called cancrum oris (noma), and the perineal form is called Fournier’s
gangrene. Idiopathic scrotal gangrene, however, is different in aetiol-
4
ogy, extent, and clinical presentation from Fournier’s gangrene.
NF poses a serious surgical challenge not only because of its rapid
and progressive nature, but also because of its attending high morbidity
and mortality. 6,7
Demographics
There is a general paucity of literature, particularly in Africa, on the
exact incidence of NF, although one hospital-based report suggests two
to three children are seen in most major tertiary health institutions every
year; that report, however, excluded cancrum oris and Fournier’s gan- Figure 21.1: NF involving the anterolateral trunk and thigh in a 14-year-
old obese but otherwise previously normal girl (before and after the first
8
grene. There had been reports of cases in Europe and North America, debridement). Note the relatively unaffected abdominal wall muscles.
especially during World War II, but more recent reports are from the
developing countries of Africa, Asia, and South America. 6,8–11 There is
no gender or age preference, but studies would suggest that the trunk
and the head and neck are more frequently involved in children. 8,12
Pathology
Aetiology
Although NF may start spontaneously in apparently normal children,
it is most often associated with pathological conditions related to
impaired host response leading to lowered immunity. 3–8,13 Some recog-
nised predisposing factors include:
1. Debilitating state, such as anaemia and malnutrition, for which
protein and vitamin B deficiencies appear predominant in importance.
Other conditions, such as obesity (Figure 21.1), diabetes mellitus, and
cancer, play greater roles in adults than children. In recent years, human
immunodeficiency virus/ acquired immune deficiency syndrome (HIV/
AIDS) is becoming increasingly significant.
2. Trauma (or specific infection), such as needle pricks, skin
abrasions, punctures, lacerations, or friction on cheek mucosa by
an abnormally positioned tooth, could sometimes be trivial and go
unnoticed. Occasionally, the trauma could be severe, such as those Figure 21.2: Necrotising fasciitis following colostomy.
following road traffic accidents. NF can complicate such surgical
procedures as colostomy (Figure 21.2), appendectomy, herniotomy,