Evaluation of LRINEC Scoring System for Diagnosis of Necrotizing Fasciitis in Patients Presenting with Soft Tissue Infections

Author(s): Pratheek K.C.1 , Prajwal K.C.2 , Bhanupriya H.3

BACKGROUND Necrotising fasciitis is an aggressive form of soft tissue infection which, even with modern medical care, has a high mortality rate. Early diagnosis and aggressive treatment are the cornerstones of therapy and any tests that can reliably decrease the interval between presentation and definitive therapy is likely to improve patient outcomes. Paucity of specific cutaneous signs to distinguish necrotizing fasciitis from other soft tissue infections such as cellulitis makes the diagnosis extremely difficult. So, a scoring system which is easy to follow and cost effective with high positive and negative predictive value is required. One such scoring system is the LRINEC scoring system devised by Wong et al in 2005 which claims to have a positive predictive value of 92.0% and negative predictive value of 96.0%. Hence we would like to evaluate this scoring system in our patients and if found to have similar comparable predictive values, it would prove to be a boon to developing countries like India where the mortality of the disease ranges from 7 to 76% and also where there resource constraint. METHODS All patients visiting the Department of Surgery, RRMCH Bangalore with soft tissue infection from Nov 2017 to April 2019 were included in this prospective study. Upon admission, blood tests (Hb%, Total WBC, RBS, CRP, Sr. Creatinine & Sr. Sodium) included in the LRINEC scoring system were done. Preoperative score is given and correlated with histopathological examination results. Using 2 X 2 table specificity, sensitivity, positive predictive value & negative predictive value were determined. RESULTS In our study, LRINEC scoring system had a sensitivity of 90.90%, specificity of 87.5%. It has a positive predictive value of 95.23% & negative predictive value of 77.78%. LRINEC score in diagnosing necrotizing fasciitis is statistically significant (p<0.001). CONCLUSIONS LRINEC scoring can be used as a diagnostic tool in patients presenting with soft tissue infection to diagnose & treat necrotising fasciitis at the earliest as it is often mistaken for milder forms of soft tissue infections such as Cellulitis or Lymphangitis, particularly in a developing country like India where resources are limited.