A comparison of necrotising fasciitis in diabetics and non-diabetics: a review of 127 patients.
OBJECTIVE
Diabetes mellitus is the most common co-morbidity associated with necrotising fasciitis. This study aims to compare the clinical presentation, investigations, Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) score, microbiology and outcome of management of this condition in diabetic and non-diabetic patients.


METHODS
The medical records of all patients with surgically proven necrotising fasciitis treated at our institution between 2005 and 2014 were reviewed. Diagnosis of necrotising fasciitis was made on findings of 'dishwater' fluid, presence of greyish necrotic deep fascia and lack of bleeding on muscle dissection found intra-operatively. Information on patients' demographics, presenting symptoms, clinical signs, investigations, treatment and outcome were recorded and analysed.


RESULTS
A total of 127 patients with surgically proven necrotising fasciitis were included in this study. In all, 78 (61.4%) were diabetic and 49 (38.6%) were non-diabetic. Diabetics tended to have polymicrobial infections (p = 0.03), renal impairment (p < 0.001), end-stage renal disease (p = 0.001) and multiple co-morbidities (p < 0.001). They presented atypically, with less tenderness (p = 0.042) and less hypotension (p = 0.034). This resulted in higher rates of misdiagnosis (p = 0.038) and a longer time to surgery (p = 0.05) leading to longer hospital stays (p = 0.043) and higher rates of amputation (p = 0.045). However, the rate of mortality is comparable (p = 0.525). A LRINEC score of > 8 appears to be more sensitive in diabetic patients (p < 0.001). However, the increased sensitivity in diabetic patients may be related to hyperglycemia and electrolyte abnormalities associated with renal impairment in these patients.


CONCLUSIONS
The LRINEC score must be used with caution in diagnosing necrotising fasciitis in diabetic patients. A high index of suspicion is key to the early diagnosis and subsequent management of these patients. Cite this article: Bone Joint J 2016;98-B:1563-8.
National University Hospital, 1E Kent Ridge Road, NUHS Tower Block Level 11, 119228, Singapore.
J H
JH
Tan
National University Hospital, 1E Kent Ridge Road, NUHS Tower Block Level 11, 119228, Singapore.
B T H
BT
Koh
National University Hospital, 1E Kent Ridge Road, NUHS Tower Block Level 11, 119228, Singapore.
C C
CC
Hong
National University Hospital, 1E Kent Ridge Road, NUHS Tower Block Level 11, 119228, Singapore.
S H
SH
Lim
National University Hospital, 1E Kent Ridge Road, NUHS Tower Block Level 11, 119228, Singapore.
S
S
Liang
National University Hospital, 5 Lower Kent Ridge Road, Main Building Level 1, 119074, Singapore.
G W H
GW
Chan
National University Hospital, 1E Kent Ridge Road, NUHS Tower Block Level 11, 119228, Singapore.
W
W
Wang
National University Hospital, 1E Kent Ridge Road, NUHS Tower Block Level 11, 119228, Singapore.
A
A
Nather
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D048909:Diabetes Complications / Q000175:diagnosis* / Q000382:microbiology; D042241:Early Diagnosis; D019115:Fasciitis, Necrotizing / Q000150:complications / Q000175:diagnosis* / Q000382:microbiology; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D055815:Young Adult
D015415:Biomarkers
Diabetes; Laboratory Risk Indicator for Necrotising Fasciitis score; Necrotising fasciitis; Non-diabetes; Outcome; Soft-tissue infections