WP7.16 - Usefulness of Cross-Sectional Imaging and Biochemical Markers in Diagnosing Necrotising Soft Tissue Infections

Abstract Introduction Diagnosis of Necrotising Soft Tissue Infections (NSTI) remains clinical, however pre-operative investigations and radiology may be useful for cases of diagnostic uncertainty or pre-operative planning. Aims To identify if cross-sectional imaging is useful in the diagnosis of NSTI's. To identify if Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) score supports the diagnosis of NSTI’s. Methods Retrospective data collection of all relevant clinical data for all histologically confirmed NSTI’s in a single centre from 2012 to 2022 inclusive. Results 73 total cases of NSTI were confirmed. 27 patients underwent CT imaging as a direct result of their presenting complaint. CT was performed for the following reasons,Patient NoReason for CT10Clinically confirmed - CT to assess extent of involvement4Clinically suspicious – CT to confirm diagnosis5No clinical diagnosis – CT features of NSTI8Incidental findings – CT for alternative diagnosis Only 3 patients had a prospective documented LRINEC score. As such retrospective LRINEC scores were calculated for each case in this cohort. Average scores were 7.71 (Range 4-13), which is above the reported threshold value of 6. Conclusion CT scans are useful in clinically confirmed or suspected NSTIs for further assessment, however with regards to diagnosing NSTIs, clinical diagnosis remains the preferred modality. There remains limited data to suggest that a CT scan should be gold standard in identifying and confirming NSTI’s. LRINEC scoring however should be utilized for all suspected NSTI’s, it remains poorly utilized but would provide significant value and diagnostic guidance when above threshold values.