Utility of neutrophil gelatinase-associated lipocalin in identifying septic cavitary effusions in dogs.

Abstract

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) is an accurate marker of septic cavitary effusions in people. HYPOTHESIS/OBJECTIVES: To evaluate the utility of serum and effusion NGAL concentrations in differentiating septic effusions from effusions caused by other etiologies in dogs. ANIMALS: Fifty dogs with pleural or peritoneal effusion. METHODS: Ten dogs were prospectively enrolled into each of 5 groups based on effusion etiology: hypoalbuminemia, increased hydrostatic pressure, neoplastic, inflammatory, and septic. Concentrations of NGAL were measured in both serum and effusion. RESULTS: While median serum NGAL concentrations did not significantly differ between dogs with hypoalbuminemia (24.8&#xa0;ng/mL, range 5.0-110.0&#xa0;ng/mL), increased hydrostatic pressure (13.2&#xa0;ng/mL, range 5.8-46.9&#xa0;ng/mL), abdominal neoplasia (13.8&#xa0;ng/mL, range 3.2-27.3&#xa0;ng/mL), inflammatory (15.8&#xa0;ng/mL, 5.6-36.6&#xa0;ng/mL), or septic causes (19.2&#xa0;ng/mL, range 7.2-64.8&#xa0;ng/mL) of effusion (P&#xa0;=&#xa0;.272), median effusion NGAL concentrations were significantly higher in the septic group (194.4&#xa0;ng/mL, range 120.0-1471.1ng/mL) than in the hypoalbuminemic (10.7&#xa0;ng/mL, range 4.1-27.8&#xa0;ng/mL, P&#xa0;<&#xa0;.001), hydrostatic (22.7&#xa0;ng/mL, range 11.3-56.7&#xa0;ng/mL, P&#xa0;<&#xa0;.001), neoplastic (65&#xa0;ng/mL, range 15.7-215.3&#xa0;ng/mL, P&#xa0;<&#xa0;.001), or inflammatory (45&#xa0;ng/mL, range 33.8-195&#xa0;ng/mL, P&#xa0;<&#xa0;.001) groups. CONCLUSIONS AND CLINICAL IMPORTANCE: Concentrations of NGAL in effusions were significantly higher in septic effusions than in effusions of other etiologies. These findings suggest that effusion NGAL concentrations could be a helpful marker in the identification of cases with septic effusion.