Evaluation of laboratory risk indicator for necrotizing fasciitis score as an early diagnostic tool for necrotizing fasciitis: a prospective observational study

Introduction

From its historical identification to modern times with advancements in management modalities globally, the mortality of necrotizing fasciitis (NF) is high ranging from 19 to 30% for all affected sites. Although many diagnostic adjuncts have been developed to assist with the prompt and accurate diagnosis of NF, the primary diagnosis is still based on high clinical suspicion. The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score was developed as a tool for distinguishing NF from other soft tissue infections. The main objective of this study is to evaluate LRINEC as a tool for early diagnosis of NF and differentiating it from other soft tissue infections like cellulitis.

Methods

This is a single-centered, prospective observational study. Patients presenting with soft tissue infections of the limbs to the emergency department from November 2020 to October 2021 were included in this study. The clinical findings and blood parameters for the LRINEC score were collected and the score was calculated. Based on clinical suspicion of NF, patients underwent debridement and had a tissue biopsy to confirm the diagnosis. The data obtained was analyzed using SPSS version 24 and MS Excel. The AUC curve was used to calculate a cutoff, sensitivity, specificity, positive predictive value, and negative predictive values for the LRINEC score based on our study.

Results

Forty-five patients with 28 males and 17 females were included. The average age was 53.667 years within a range of 19-79 years. Among them 44.4% of the patients had NF and 66.6% had other minor forms of soft tissue infections. The ROC curve obtained a cutoff value of greater than or equal to 6, with an AUC of 0.751. At this cut of value study showed a sensitivity of 85% with a specificity of 52%. Similarly, positive predictive value was found to be 58.62%, negative predictive values of 81.25%, and overall accuracy of 66.67% in early diagnosis of NF.

Conclusion

In conclusion, our study showed that the LRINEC score can be a reliable tool for the early diagnosis of NF in an ED setting. This scoring system is best to be used to rule out NF.

Predictive Value of Cerebrospinal Fluid Lactate Level for the Diagnosis of Bacterial Meningitis following Cranial Surgery

Background:To distinguish post-neurosurgical bacterial meningitis (PNBM) from aseptic meningitis is difficult. Inflammatory and biochemical cerebrospinal fluid (CSF) changes mimic those classically observed after CNS surgery. CSF lactate assay has therefore been proposed as a useful PNBM marker. Objective:To determine the value of cerebrospinal fluid (CSF) lactate level for the identification of bacterial meningitis following cranial surgery. Methods:Between January 2016 and December 2016, a prospective clinical study was done in Department of Neurosurgery, in which all patients with clinical suspicion of PNBM were enrolled. Patients with clinical suspicion of bacterial meningitis BM were categorized, according to preset criteria, into 3 groups: (1) proven BM; (2) presumed BM, and (3) nonbacterial meningeal syndrome. CSF markers were plotted in a receiver operating curve (ROC) to evaluate their diagnostic accuracy. Results:The study included 70 patients. We obtained 65 CSF samples from patients with clinical suspicion of BM by CSF analysis. 20 corresponded to proven BM, 7 to probable BM and 38 to excluded BM. Mean lactate in CSF was: 8.4 ±3.0 mmol /l for proven BM, 4.8 ± 0.99 mmol /l for probable BM and 2.08 ± 0.822 mmol/l for excluded BM (P < .001). Conclusion: CSF lactate level has good predictive value to distinguish BM from aseptic meningitis with sensitivity of 90% and specificity: 87% at cut-off value: 4.0 mmol/l.

Comparison of the use of neutrophil: lymphocyte count ratio (NLCR) to total leukocyte count in diagnosing appendicitis in adults with right iliac fossa pain

Introduction: Diagnosis of acute appendicitis (AA) is purely based on history, examination and few laboratory investigations. However, it is often a perplexing diagnostic problem during the early stages of the disease. Failure to make an early diagnosis is a primary reason for morbidity and mortality. Elevated leukocyte count is one of the indicators of appendiceal inflammation in patients with right iliac fossa pain and most of the patients with acute appendicitis present with leucocytosis. Recently, it has been seen that the neutrophil: lymphocyte count ratio (NLCR) is a more sensitive marker than leukocytosis in patients with acute appendicitis. Method: This is a prospective observational study conducted over a period of one year in the department of surgery at the Tribhuvan University Teaching Hospital, from September 2013 to August 2014. The clinical diagnosis of Acute appendicitis was made by history and clinical examinations and laboratory investigations. Total leukocyte count (TLC) and NLCR of patients diagnosed as AA were measured and recorded in the pro forma. Histological diagnosis was taken as the final diagnosis. Results: A total of 106 patients were included in the study. Two third of the patients were male. Right iliac fossa tenderness was the most common sign. Ultrasound was able to diagnose acute appendicitis in 40.65% of the cases. NLCR> 3.5 was observed in 90.56% of patients with acute appendicitis, whereas 78.3% of patients had leukocytosis only. High NLCR (5.60) is associated with complicated AA. Conclusion: NLCR is a more sensitive laboratory parameter than TLC in patients with RIF pain to diagnose acute appendicitis. A high NLCR ratio has a high likelihood of a complicated AA.