Using clinical pathways to aid in the diagnosis of necrotizing soft tissue infections synthesis of evidence.

BACKGROUND

Necrotizing soft tissue infections (NSTIs) are rare, rapidly spreading infections that occur in the soft tissue compartments. The mortality rate is high and has been found to decrease if patients are treated early and aggressively with surgical debridement and broad-spectrum antibiotics. Unfortunately these infections present similarly to other types of skin and soft tissue infections (SSTIs) making diagnosis difficult.

AIMS: This paper reviews the evidence surrounding the early diagnosis of NSTIs. This was used to develop a clinical practice guideline (CPG) for implementation in the emergency department (ED) setting to assist the provider in distinguishing NSTIs from SSTIs to potentially decrease the time from presentation to diagnosis.

METHODS

A review of the literature was performed. Studies were identified and critiqued by two reviewers independently for clinical relevance, study design, and statistical analysis.

RESULTS

Signs and symptoms, or "hard signs," associated with NSTIs include: pain out of proportion to the exam, rapidly spreading infection, presence of bullae, skin ecchymosis or sloughing, gas in the tissues, skin anesthesia, edema extending beyond the erythema, and symptoms of sepsis. Unfortunately only 43% of the patients with an NSTI will present with these signs. Studies have found an association between laboratory values and NSTIs with the most commonly associated findings being leukocytosis, azotemia, and hyponatremia. Using these complimentary clinical and laboratory values, the Laboratory Risk Indicator for NECrotizing fasciitis (LRINEC) score is an emerging tool that providers can use to determine the risk of an NSTI. A clinical pathway was developed and implemented in the ED for all patients presenting with an SSTI to assist providers in confirming or negating the presence of an NSTI.

IMPLICATION FOR PRACTICE: Educating ED providers about the signs, symptoms, and laboratory findings associated with NSTIs will lead to earlier diagnosis and treatment and decreased morbidity and mortality.