Use of admission serum neutrophil gelatinase-associated lipocalin (NGAL) concentrations as a marker of sepsis and outcome in neonatal foals.

BACKGROUND: Equine neonatal sepsis can be challenging to diagnose and prognosticate. Neutrophil gelatinase-associated lipocalin (NGAL), a new marker of renal damage and inflammation, can potentially be helpful. OBJECTIVES: To evaluate NGAL in neonatal foals with sepsis, and assess its relation to outcome. ANIMALS: Foals ≤ 14 days, with admission blood analysis and stored serum. METHODS: NGAL was measured on stored serum from 91 foals. Foals were scored for sepsis and survival and categorized according to sepsis status (septic, sick non-septic, healthy, and uncertain sepsis status) and outcome groups (survivors and non-survivors). The septic foals were further sub-categorized according to severity (normal sepsis, severe sepsis and septic shock). A Kruskal-Wallis test was used to compare serum NGAL concentrations in survivors and non-survivors, in the sepsis status groups, and in the sepsis severity groups. Optimal cut-off values for serum NGAL concentrations to diagnose sepsis and outcome were determined with receiver operating characteristic (ROC) curves. NGAL was compared to creatinine and SAA. RESULTS: Median serum NGAL concentrations were significantly higher in septic than non-septic foals. However, serum NGAL concentrations did not differ between sepsis severity subgroups. Serum NGAL concentrations were significantly lower in survivors than in non-survivors. Optimal cut-off values of serum NGAL concentrations were 455 µg/L (sensitivity 71.4%, specificity 100%) and 1104 µg/L (sensitivity 39.3%, specificity 95.2%) for predicting sepsis and non-survival, respectively. NGAL correlated to SAA, but not to creatinine. NGAL performed similarly to SAA to diagnose sepsis. CONCLUSION: Serum NGAL concentrations may be useful for diagnosing sepsis and predicting outcome.

Transthoracic echocardiography and its limitations in the diagnosis of congenital supernumerary aortic valve in a Thoroughbred.

Aortic valve malformation is a common congenital abnormality reported in human medicine. The malformation is characterised by an increased or decreased number of cusps. Anatomical variations of the aortic valve that have been documented in humans include unicuspid, bicuspid, quadricuspid and quinticuspid valves. Two reports described a quadricuspid aortic valve in horses associated with either a ventricular septal defect (VSD) or tetralogy of Fallot. In this case report we describe the clinical and echocardiographic findings of a horse with a quadricuspid aortic valve as single congenital abnormality, referred with history of exercise intolerance and an episode of paroxysmal atrial fibrillation. Limitations and risks of misdiagnosis that can be encountered with transthoracic echocardiography are also discussed. The reported case highlights the importance of echocardiographic screening in asymptomatic patients as congenital heart disease can be present without obvious cardiac signs. As advanced imaging on the equine thorax is still far from future possibilities for adult horses, this report may help to reach an accurate diagnosis with similar cases.

Ascending aortic aneurysm associated with tetralogy of Fallot in an adult mare.

Congenital heart disease is relatively uncommon in horses. Only three reports exist that describe a tetralogy of Fallot in adult horses. Whereas in humans the presence of congenital heart disease constitutes a risk factor for developing aortic aneurysms, their association has never been reported in horses. Here, we present a case with a large ascending aortic aneurysm as a complication of a tetralogy of Fallot in an adult mare. The mare was referred with sustained tachycardia and a 5 days history of mild intermittent colic, depression, inappetence and weight loss. Echocardiography was used to characterize the cardiac abnormalities and aortic root dilation. Due to the poor prognosis, the mare was euthanized and post-mortem examination further characterized the abnormalities. At least four factors contributed in this case to the development of aortic haematoma: congenital disease, mucoid extracellular matrix accumulation vasa vasorum dysfunction and inflammatory/degenerative lesions in the aorta's intima. Although colic is primarily caused by gastrointestinal issues, cardiac disease should be suspected in cases with sustained tachycardia, even in absence of murmurs or arrhythmias. Despite the fact that congenital abnormalities are usually detected in foals, they may sometimes remain unnoticed for several years.

Validation of an ELISA for detection of neutrophil gelatinase-associated lipocalin (NGAL) in equine serum.

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) has been shown to be a useful marker of kidney injury in people and dogs, but has not been described in horses. OBJECTIVES: The aim of the study was to validate a commercially available porcine-specific ELISA to measure serum concentrations of equine NGAL. METHODS: Intra- and interassay imprecisions were evaluated by multiple measurements on equine serum pools. Assay inaccuracy was determined by the linearity under dilution. Overlapping performance was assessed by measuring NGAL concentrations in horses with normal and elevated serum creatinine levels. RESULTS: Intra- and interassay imprecision (coefficient of variation) ranged from 5.35% to 28.39%. The ELISA showed no signs of inaccuracy. Overlapping performance was acceptable, as the assay was able to detect the expected differences of NGAL levels in horses with normal and elevated serum creatinine concentrations. CONCLUSIONS: Equine serum NGAL concentrations could be quantified reliably using the porcine-specific ELISA.