Serum NT-pCNP blood test for diagnosing sepsis in dogs

Abstract

BACKGROUND: There is a need for diagnostic biomarkers that can rapidly differentiate dogs with sepsis from dogs with noninfectious forms of systemic inflammatory response syndrome (NSIRS). OBJECTIVES: To compare serum NT-pCNP concentrations among dogs with various forms of sepsis, NSIRS, and healthy controls and to evaluate the use of serum NT-pCNP for the diagnosis of various forms of sepsis in dogs. ANIMALS: One hundred and twelve dogs including 63 critically ill dogs (sepsis n = 29; NSIRS n = 34) and 49 healthy control dogs. METHODS: Prospective clinical investigation. Serum samples were collected for NT-pCNP measurement from dogs with sepsis or NSIRS within 24 hours of intensive care unit admission or at the time of presentation for healthy dogs. Dogs with sepsis were subclassified based on the anatomic region of infection. Serum NT-pCNP concentrations were compared among sepsis, NSIRS and healthy groups as well as among sepsis subgroups. The area under the curve (AUC), sensitivity, and specificity for identifying dogs with sepsis were determined. RESULTS: Using a cut-off value of 10.1 pmol/L, AUC, sensitivity, and specificity of NT-pCNP for differentiating dogs with sepsis from dogs with NSIRS or healthy control dogs were 0.71 (95% CI, 0.58-0.85), 65.5% (45.7-82.1%), and 89.2% (80.4-94.9%), respectively. Serum NT-pCNP had poor sensitivity for peritoneal sources of sepsis; AUC [0.92 (0.81-1.0)], sensitivity [94% (71-100%)], and specificity [89% (80-95%)] improved when these dogs were excluded. Serum NT-pCNP concentration was not associated with survival in the sepsis group. CONCLUSIONS AND CLINICAL IMPORTANCE: Serum NT-pCNP is a promising diagnostic biomarker for sepsis but is a poor indicator of septic peritonitis.