NECROTIZING SOFT TISSUE INFECTION BY SERRATIA MARCESCENS: AN EARLY DIAGNOSIS WITH THE UTILIZATION OF LABORATORY RISK INDICATOR FOR NECROTIZING FASCIITIS (LRINEC) SCORE

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Necrotizing soft tissue infections (NSTIs) include a vast array of necrotizing forms that affect the deeper layers tissues including fasciitis and myositis. Though rare, with approximately 500 to 1500 estimated cases per year, many providers find diagnosis difficult due unaffected appearance overlying on initial presentation. This case showcases complexities Type II-Monomicrobial NSTI-Serratia Marcescens, benefit utilizing Laboratory Risk Indicator for Fasciitis (LRINEC) score, early identification NSTIs. CASE PRESENTATION: A 66-year-old-male history DM complaint left lower extremity edema. He reported an insidious onset swelling started five days prior arrival no precipitating or consequential factors. was hemodynamically stable 3+ pitting edema extending beyond thigh, erythema below knee blisters medial aspects leg. Serum studies showed D-Dimer 12.6, CRP 1.9, ESR 29. Venous doppler consistent extensive deep vein thrombosis CT imaging negative abscess subcutaneous air. treated IV Clindamycin therapeutic anticoagulation. Days later, cellulitis had progressed nearly three times original size worsening leukocytosis, 111, 17.5. surgical debridement multiple cavitary abscesses. Pathology infection Serratia M. prolonged course Pip-Tazo Vancomycin, eventual preservation function. DISCUSSION: NSTI has rapid clinical is associated high mortality, ranging 14-39%. Early signs are dubious mimic simple which evolve in days. M., extremely rare atypical only 17 cases. It opturnitistic affecting immunocompromised, it thrives higher concentrations activating cascades hyperreactive cellular responses. Inflammatory mediators upregulate factors VII VIIa reduce anti-coagulation proteins pro-thrombotic event. Initially, unclear if patient LRINEC score 2/12. The second encounter, his 7/12, suggestive NSTI. final indicated positive predictive value 92%. study by Wong et. al. performed prospective resulting 92% 96% suggesting be beneficial tool. CONCLUSIONS: identifying early. crucial, between 85-100% initially missed often confused myositis, DVT, cellulitis, abscess. index suspicion imperative lieu absent cutaneous findings disease process. REFERENCE #1: Goldstein, Ellie J. C., et "Necrotizing Soft-Tissue Infection: Diagnosis Management." OUP Academic, Oxford University Press, 1 Mar. 2007, academic.oup.com/cid/article/44/5/705/348724. #2: www.samsonconsulting.co.uk. Misdiagnosing Necrotising Fasciitis, www.glynns.co.uk/necrotising-fasciitis/misdiagnosing-necrotising-fasciitis.php. #3: Guberman, Ronald. "Case Study: Treating Caused By Marcescens." Podiatry Today, 24 Aug. 2011, www.podiatrytoday.com/treating-necrotizing-fasciitis-caused-iserratia-marcescensi. DISCLOSURES: No relevant relationships Swetha Paduri, source=Web Response Nehal Patel, Charmi Paul Roach,