LRINEC Score for Necrotizing Soft Tissue Infection

Calculators Infectious Diseases

LRINEC Score for Necrotizing Soft Tissue Infection is an effective tool utilized to screen the bacterial infection as well as necrotizing soft tissue infection

Calculator
Background
Authors
References

C-reactive protein

<15 mg/dL (150 mg/L) 0

≥15 mg/dL (150 mg/L) 4

White blood cell count(x10,000/µL)

<15 0

15-25 1

>25 2

Hemoglobin (g/dL)

>13.5 0

11-13.5 1

<11 2

Sodium (mEq/L)

≥135 0

<135 2

Creatinine

≤1.6 mg/dL (141 µmol/L) 0

>1.6 mg/dL (141 µmol/L) 2

Glucose

≤180 mg/dL (10 mmol/L) 0

>180 mg/dL (10 mmol/L) 1

Result:

Background

Measured Factor

LRINEC Score

Measured Factor Disease

Necrotizing soft tissue infection
Severe bacterial infection

Measured Factor Detail

LRINEC Score for Necrotizing Soft Tissue Infection is used to diagnose or screen the bacterial infections. It is applied when the patient includes a concerning history of rapidly progressive cellulitis. It may be helpful for providing the overall gestalt image of a patient with a potential necrotizing soft tissue infection or severe bacterial infection. The calculation takes into account patient features such as total white blood cell count, hemoglobin, sodium, glucose, serum creatinine, and C-reactive protein.

Speciality

Cosmetologist

Body System

Infectious Diseases

Measured Factor Low Impact

Score ≤5 indiactes necrotizing fasciitis low risk

Measured Factor High Impact

Score 6–7 illustrates necrotizing fasciitis moderate risk
Score ≥8 illustrates necrotizing fasciitis high risk

Result Interpretation

Ranges Ranges

Critical High: ≥8
Normal: 0-4
Normal Adult Male: 0-4
Normal Adult Female: 0-4
Normal Geriatric Male: 0-4
Normal Geriatric Female: 0-4

Result High Conditions

Necrotizing Fasciitis
Severe bacterial infection

False Positive

Cases of confirmed cellulitis showed the high false positive rates

References: 1

Test Limitations

LRINEC score was unable to diffrentiate patients with
suspected NF due to a lack of CRP measured levels

References: 2

Studies

Study Validation 1

The aim of this 10-year retrospective study was to analyze the capability of the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score to distinguish Necrotizing fasciitis (NF) infection from other similar other soft tissue infections such as cellulitis or abscess. 948 patients of ≥18 years old with a diagnosis of cellulitis or NF were involved in the study. Patients were categorized into three categories based on their LRINEC score (0-13): high risk (LRINEC score ≥8), moderate risk (LRINEC score 6-7), and low risk (LRINEC score ≤5. Their CRP values were calculated using lab methods. This study concludes that due to demonstration of a high flase positive and false negative rate this tool needs further validation studies with improvemetns

References: 3

Study Validation 2

This validation cohort study was conducted from 2003 to 2010 in order to validate the LRINEC score in early recognition of necrotizing fasciitis (NF). All the patients in the emergency department were reviewed for pathological diagnoses. A total of 233 patients with necrotizing fasciitis and 3155 with severe cellulitis were recruited in this study. A LRINEC score ≥6 had a sensitivity of 59.2% (CI 52.9–65.6%), specificity of 83.8% (CI 81.9–85.7%), likelihood ratio of 3.89, positive predictive ratio of 37.9% (95% CI 32.9–42.9%), and negative predictive ratio of 92.5% (95% CI 91.0–94.0%) which was compared with the rate of clinical diagnosis of NF.This study concluded that LRINEC score gave good results which makes it a impressive diagnostic tool to identify patients with NF from other severe soft tissue infections

References: 4

Study Validation 3

This retrospective observational study was conducted to develop a novel diagnostic scoring system for distinguishing necrotizing fasciitis from other soft tissue infections. 89 patients with necrotizing fasciitis and 225 patients with severe cellulitis or abscesses were involved in the study. . Total white cell count, hemoglobin, sodium, glucose, serum creatinine, and C-reactive protein were selected were various parameters based on which LRINEC score was assigned to patients. Univariate and multivariate logistic regression was used to select significant predictors. The cutoff value for the LRINEC score was 6 scores with a positive predictive value of 92.0% and negative predictive value of 96.0%. This study concluded that performance of LRINEC score was up to the mark and this tool was capable of detecting even clinically early cases of necrotizing fasciitis

References: 5

Study Additional 1

The objective of this retrospective study was to determine the performance and utilization of Laboratory Risk Indicator in Necrotising Fasciitis (LRINEC) score. Patients admitted to facility between January 2002 and December 2005 was analyzed for diagnosis of necrotising fasciitis. LRINEC score were assigned to the patients upon the initial blood tests. The sensitivity, specificity and likelihood ratios were then calculated for patients with a LRINEC score of > or = 6 compared with the findings of a surgical biopsy. 28 eligible patients with confirmed NF were included in the study. With a cut-off score of > or = 6, the LRINEC score had a sensitivity of 80%, specificity of 67%, a positive predictive value of 57% and a negative predictive value of 86% in distinguishing the patients with proven necrotising fasciitis from those with severe soft tissue infections. This study suggested that the LRINEC score would have only a very minimal effect on the post-test probability of the patients with NF

References: 6

Study Additional 2

This study was conducted to check out whether certain higher LRINEC score is associated with mortality and other outcomes of patients with necrotizing soft-tissue infections (NSTI). A total 209 patients were recruited in the study and were analyzed for NF. LRINEC scores for each patient were calculated. The primary outcomes measured were mortality rate and amputation rate. Patients were scrutinized into 2 groups: Group (I) was those whose LRINEC score was <6 and group (II) was those whose LRINEC score was > or =6. The overall mortality rate was found to be 33 of 209 (15.8%) and amputation rate was 55 of 209 (26.3%). Significant differences in mortality rate (P = 0.04) and amputation rate (P = 0.002) were noted between two groups. This study concluded that there is strong correlation between LRINEC score and mortality among patients with NF

References: 7

Study Additional 3

This 5 year retrospective study was performed October 2006 to October 2011 with aim to validate the Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) scoring system. Among all, 15 patients with median age of 51 years were diagnosed with necrotising fasciitis. The LRINEC score was calculated for each patient to evaluate its performance. Three patients died and from remaining 5 patients had Group A Streptococcus as infective agent. Other monomicrobial agents included Group G Streptococcus and Klebsiella pneumoniae. This study concluded that LRINEC system was insensitive as it could diagnose less amount of patients with NF and had high negative predictive value.

References: 8

References

Neeki MM, Dong F, Au C, et al. Evaluating the Laboratory Risk Indicator to Differentiate Cellulitis from Necrotizing Fasciitis in the Emergency Department. West J Emerg Med. 2017;18(4):684-689.
Bharadwaj, Ragya, Adil Mahmud Ali, and Nafis Ahmad Faruqi. "Use of Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) Score in differentiating Necrotising Fasciitis cases from Soft tissue infections: A Prospective Study." Hemoglobin 25: 2.
Neeki MM, Dong F, Au C, Toy J, Khoshab N, Lee C, et al. Evaluating the Laboratory Risk Indicator to Differentiate Cellulitis from Necrotizing Fasciitis in the Emergency Department. West J Emerg Med. 2017;18(4):684-689.
Liao CI, Lee YK, Su YC, Chuang CH, Wong CH. "Validation of the laboratory risk indicator for necrotizing fasciitis (LRINEC) score for early diagnosis of necrotizing fasciitis." Tzu Chi Medical Journal 24.2 (2012): 73-76.
Wong CH, Khin LW, Heng KS, Tan KC, Low CO. The LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) score: a tool for distinguishing necrotizing fasciitis from other soft tissue infections. Crit Care Med. 2004;32(7):1535-41.
Holland MJ. Application of the Laboratory Risk Indicator in Necrotising Fasciitis (LRINEC) score to patients in a tropical tertiary referral centre. Anaesth Intensive Care. 2009;37(4):588-92.
Su YC, Chen HW, Hong YC, Chen CT, Hsiao CT, Chen IC. Laboratory risk indicator for necrotizing fasciitis score and the outcomes. ANZ J Surg. 2008;78(11):968-72.
Swain RA, Hatcher JC, Azadian BS, Soni N, De souza B. A five-year review of necrotising fasciitis in a tertiary referral unit. Ann R Coll Surg Engl. 2013;95(1):57-60.