Validation of a commercial 1,2-o-dilauryl-rac-glycero glutaric acid-(6'-methylresorufin) ester lipase assay for diagnosis of canine pancreatitis

Evaluation of the clinical usefulness of pancreatic alpha amylase as a novel biomarker in dogs with acute pancreatitis: a pilot study

Pancreatic alpha amylase (P-AMY) is used as a biomarker of acute pancreatitis (AP) in human medicine. To our knowledge, there are no studies evaluating the usefulness of P-AMY in dogs with AP. In this study, we evaluated the diagnostic value of P-AMY, currently not verified in veterinary medicine. The AP group (n = 40) consisted of dogs with AP diagnosed using clinical signs and laboratory examinations, including abnormal canine pancreatic lipase (cPL) concentration, and compatible abdominal ultrasound examination at first presentation. Evaluation of the canine AP severity (CAPS) score was performed. The control group (n = 38) was composed of normal dogs without any abnormalities in clinical findings, blood exams or diagnostic imaging. The correlation of P-AMY with cPL was confirmed by Pearson's correlation analysis (r = 0.564, p < .001). The sensitivity and specificity for the most appropriate cut-off values of P-AMY were recorded similar to the values of DGGR. The dogs with AP and CAPS ≥11 had significantly higher serum P-AMY (p = .016) contrary to DGGR lipase and cPL. Furthermore, there was a significant difference in the median P-AMY dependent on the presence of systemic inflammatory response syndrome (p = .001). P-AMY showed similar level of diagnostic accuracy along with sensitivity and specificity compared to DGGR lipase. In addition, P-AMY showed a significant association with CAPS score, contrary to cPL and DGGR lipase. Along with other biomarkers associated with AP, P-AMY has the potential of usefulness as a supportive diagnostic and prognostic biomarker of AP in dogs.

Utility of 1,2-o-dilauryl-rac-glycero glutaric acid-(6'-methylresorufin)-ester-lipase for monitoring dogs with chronic pancreatitis

BACKGROUND

The utility of 1,2-o-dilauryl-rac-glycero glutaric acid-(6'-methylresorufin)-ester-(DGGR)-lipase activity (DLA) in monitoring clinical progression of chronic pancreatitis (CP) in dogs is unknown.

OBJECTIVE

To examine the association of DLA with clinical signs of CP, as assessed by a CP clinical severity score (CPCSS).

ANIMALS

Twenty-four dogs.

METHODS

This is a retrospective study. Chronic pancreatitis was diagnosed based on clinical signs and DLA > 250 U/L and monitored using CPCSS and DLA.

RESULTS

The study included 134 visits (median, 10 visits/dog; range, 2-11). Mild-moderate (CPCSS, 0-3) and severe (CPCSS, ≥4) disease were documented in 94 (70%) and 40 (30%) visits, respectively. In emergency visits (n = 44; 33%) CPCSS (median, 5; range, 0-15) and DLA (median, 534 U/L; range, 63-7133) were higher (P < .001 and P = .003, respectively) than in scheduled ones (n = 90; 67%; median, 1; range, 0-6 and median, 384 U/L; range, 49-3747, respectively). DGGR-lipase activity was associated (P = .009) with the CPCSS, with a lower activity documented in mild-moderate CPCSS (median 391 U/L; range, 49-3747), compared to severe score (median, 558 U/L; range, 63-7133). DGGR-lipase activity was significantly, but weakly, correlated with CPSS (r = 0.233, P = .007). DGGR-lipase activity inefficiently discriminated mild-moderate vs severe CP (area under the receiver operator characteristics curve, 0.64; 95% confidence interval, 0.53-0.75; P = .012), with DLA cutoff of 428 U/L corresponding to sensitivity of 65% and specificity of 63%.

CONCLUSIONS AND CLINICAL IMPORTANCE

Increased DLA is associated with emergency revisits in dogs with CP, possibly reflecting acute flare-ups. DGGR-lipase activity was associated with the CPCSS over the follow-ups but could not differentiate disease severity.

Retrospective analysis of association between hepatopathy and serum DGGR lipase activity in dogs: a pilot study

1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6′-methylresorufin) ester (DGGR) lipase assays are used to measure lipase activity in the diagnosis of pancreatitis. The effect of hepatic lipases released from damaged hepatocytes on serum DGGR lipase activity has not been reported, to our knowledge. We identified dogs with histologically confirmed liver lesions and concurrent unremarkable pancreatic histology, and dogs with no histologic evidence of hepatic or pancreatic disease. Dogs with relevant comorbidities were excluded. The hepatopathy group (n = 7) included 4 dogs with inflammatory hepatopathies, 2 with hepatic neoplasia, and 1 with unspecified (non-inflammatory, non-neoplastic) hepatopathy. The control group (n = 5) included one dog each with enteritis, subcutaneous hemangiosarcoma, hydrocephalus, myelomalacia, and tetanus. A Mann–Whitney U test compared selected biochemical parameters including serum DGGR lipase, alkaline phosphatase, alanine aminotransferase, and amylase activities, with statistical significance defined as p ≤ 0.05. Data are presented as median and range. Serum DGGR lipase activity (RI: <44 IU/L) was not different between the hepatopathy (52 IU/L; range: 27–85 IU/L) and control (37 IU/L, 25–105 IU/L; p = 0.947) groups. Serum amylase activity (RI: 256–1,610 IU/L) was significantly higher in the hepatopathy group (830 IU/L; 711–1,210 IU/L) than the control group (541 IU/L, 336–695 IU/L; p = 0.028). No association or correlation between serum DGGR lipase activity and hepatic lesions (based on histologic or biochemical findings) was identified, suggesting that clinically relevant changes in serum DGGR lipase activity may not be expected secondary to hepatopathy alone.

Accuracy of 1,2-o-Dilauryl-rac-glycero-3-glutaric Acid-(6'-methylresorufin) Ester (DGGR)-Lipase to Predict Canine Pancreas-Specific Lipase (cPL) and Diagnostic Accuracy of Both Tests for Canine Acute Pancreatitis

Different lipase assays have variable reported diagnostic accuracies for acute pancreatitis (AP) in dogs. The aims of this retrospective study were to evaluate optimal cutoffs for 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6′-methylresorufin) ester (DGGR)-lipase to predict diagnostic cutoffs of canine pancreas-specific lipase (cPL; IDEXX). DGGR-lipase activity and cPL from the same blood draw in 301 dogs with a variety of diseases were compared using Spearman’s rank correlation, Cohen’s kappa agreement, and receiver operating characteristic (ROC) curves. Activity of DGGR-lipase (10−15,616 U/L) and cPL concentrations (8.1−≥2000 µg/L) were highly correlated (rs = 0.91). Areas under the ROC curves (AUCs) to predict cPL >200 and ≥400 µg/L with DGGR-lipase were 0.97 and 0.99, with optimal cutoffs of 143 U/L (sensitivity (Se) 91.7%; specificity (Sp) 95.3%) and 205 U/L (Se 97.5%; Sp 96.4%), and Cohen’s kappa agreements of 0.87 and 0.92, respectively. AUCs for a clinical diagnosis of AP, assigned to 87/301 dogs, with DGGR-lipase (0.75) and cPL (0.76) did not differ significantly (p = 0.48); optimal cutoffs were 161 U/L for DGGR (Se 67%; Sp 81%) and 235 µg/L for cPL (Se 68%; Sp 84%). To conclude, DGGR-lipase is a highly accurate predictor of cPL with a comparable performance when used to diagnose AP in dogs.

Advances in the diagnosis of acute pancreatitis in dogs

In the last 20 years, the diagnosis of pancreatitis has become more frequent as a result of improved diagnostic modalities such as abdominal ultrasound examination, advanced imaging, and immunoassays for the measurement of pancreatic lipase. Our aim is to provide a state‐of‐the‐art overview of the clinical diagnosis of acute pancreatitis (AP) in dogs with a particular focus on pancreatic lipase assay validation and clinical performance, in addition to advanced imaging modalities. We also discuss the potential indications for cytology and histopathology in dogs with suspected AP.

The Agreement between Feline Pancreatic Lipase Immunoreactivity and DGGR-Lipase Assay in Cats-Preliminary Results

Simple Summary

Feline pancreatitis is a common disease with diagnostics requiring a combination of clinical, laboratory and imaging methods. Measuring of pancreatic lipase concentration is the laboratory mainstay of feline pancreatitis diagnostics. It can be done using immunoenzymatic assay (feline pancreatic immunoreactivity, fPLI) or colorimetric assay based on hydrolyzing a special substrate (DGGR) to a color product. A DGGR-lipase assay is manufactured by various companies. Studies carried out in cats on the DGGR-lipase assay of a single manufacturer have shown a high agreement with fPLI, however studies in dogs indicate that the performance of assays of different manufacturers may vary considerably. One of the largest Polish veterinary laboratories working 24/7 in the largest Polish cities offers the DGGR-lipase assay of a large Polish laboratory solutions provider. The values obtained in this assay are higher than those yielded by the traditional DGGR-lipase assay validated in studies carried out so far. Therefore, we decided to evaluate the agreement between the DGGR-lipase assay of the Polish manufacturer and fPLI. The agreement proved to be as high as for the traditional assay.

Abstract

The colorimetric catalytic assay based on the use of 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6′-methylresorufin) (DGGR) ester as a substrate for pancreatic lipase activity is commonly used for the diagnosis of pancreatitis in dogs and cats. Even though the assay has generally been shown to yield consistent results with feline pancreatic lipase immunoreactivity (fPLI) assay, the agreement may vary between assays of different manufacturers. In this study, the chance-corrected agreement between a DGGR-lipase assay offered by one of the biggest providers of diagnostic solutions in Poland and fPLI assay was investigated. The study was carried out on 50 cats in which DGGR-lipase activity and fPLI were tested in the same blood sample. The chance-corrected agreement was determined using Gwet’s AC₁ coefficient separately for the fPLI assay’s cut-off values of >3.5 μg/L and >5.3 μg/L. The DGGR-lipase activity significantly positively correlated with fPLI (R_s = 0.665; CI 95%: 0.451, 0.807, p < 0.001). The chance-corrected agreement between the fPLI assay and DGGR-lipase assay differed considerably depending on the cut-off values of the DGGR-lipase assay. When the cut-off value reported in the literature (>26 U/L) was used, it was poor to fair. It was moderate at the cut-off value recommended by the laboratory (>45 U/L), and good at the cut-off value recommended by the assay’s manufacturer (>60 U/L). The highest agreement was obtained between the fPLI assay at the cut-off value of 3.5 μg/L and the DGGR-lipase assay at the cut-off value of 55 U/L (AC₁ = 0.725; CI 95%: 0.537, 0.914) and between the fPLI assay at the cut-off value of 5.3 μg/L and the DGGR-lipase assay at the cut-off value of 70 U/L (AC₁ = 0.749; CI 95%: 0.577, 0.921). The study confirms that the chance-corrected agreement between the two assays is good. Prospective studies comparing both assays to a diagnostic gold standard are needed to determine which of them is more accurate.

Serum concentrations of canine pancreatic lipase immunoreactivity and C-reactive protein for monitoring disease progression in dogs with acute pancreatitis

Background

Reliable biomarkers for monitoring disease progression and management in dogs with acute pancreatitis have not been described.

Objective

To determine if serum concentrations of canine pancreatic lipase immunoreactivity (cPLI) and C‐reactive protein (CRP) can be used as biomarkers for disease progression in hospitalized dogs with acute pancreatitis.

Animals

Thirteen hospitalized dogs with acute pancreatitis diagnosed based on clinical signs, serum cPLI concentrations, and imaging findings were enrolled.

Methods

Serum cPLI and CRP concentrations were determined before and then daily during hospital management and 1 week after hospital discharge. Modified canine activity index (MCAI) and canine acute pancreatitis clinical severity index (CAPCSI) scores were calculated daily for each patient while hospitalized.

Results

The MCAI scores (P = .03) but not CAPCSI scores (P = .31) were significantly different between dogs that survived to discharge (n = 11) and those that did not (n = 2). Serum cPLI concentration was positively correlated with MCAI (rho = 0.42; P = .01). Serum CRP concentration also was positively correlated with the MCAI (rho = 0.42, P = .01).

Conclusions

Serum cPLI and possibly CRP could be used as objective biomarkers for clinical changes in hospitalized dogs with acute pancreatitis. Additional studies involving larger numbers of dogs would be warranted to evaluate the broader impact of these findings.

Retrospective study evaluation of DGGR lipase for diagnosis, agreement with pancreatic lipase and prognosis in dogs with suspected acute pancreatitis

OBJECTIVES

Activity of 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester (DGGR) lipase is considered to be more pancreas specific than traditional lipase assays. The aim of this study was to evaluate the diagnostic performance of DGGR lipase activity for suspected acute pancreatitis in dogs and to assess its prognostic usefulness.

METHODS

Retrospective study of case records for suspected acute pancreatitis based on clinician-stated diagnosis, point-of-care and quantitative canine pancreas-specific lipase (cPL) results and consistent ultrasonographic features. Diagnostic performance of DGGR lipase was assessed by receiver-operating characteristic curve analysis, agreement by Cohen's kappa (κ) and prognostic value by multiple regression analysis.

RESULTS

Median DGGR lipase activity was significantly (P < 0.001) higher in dogs with suspected acute pancreatitis [93.7 (range, 11.0-2853.0) U/L (n = 158)] compared to those with no evidence of pancreatitis [range, 20.9 (6.7-89.0) U/L (n = 356)]. A DGGR lipase activity >42.15 U/L had the best combined diagnostic sensitivity (81.0%) and specificity (92.1%). Previously established cut-offs (>130 and >80 U/L) had sensitivities of 40.5 and 43.0%, and specificities of 100 and 99.7%, respectively. There was near perfect (κ = 0.821) and substantial (κ = 0.751) agreement between DGGR lipase activity >42.15 U/L and quantitative cPL concentrations ≥200 and ≥400 μg/L, respectively. DGGR lipase activity but not quantitative cPL concentration was statistically (P = 0.043, odds ratio = 0.999) predictive of discharge but clinical utility is questionable.

CLINICAL SIGNIFICANCE

Using DGGR lipase at the lower cut-off could provide an additional test for supporting a diagnosis of acute pancreatitis in dogs particularly if cPL results are not available. Larger studies are required to more fully assess its value in prognostication.

Increased canine pancreatic lipase immunoreactivity (cPLI) and 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester (DGGR) lipase in dogs with evidence of portal hypertension and normal pancreatic histology: a pilot study

The clinical presentations of both liver disease and pancreatitis are nonspecific and overlapping, which may cause difficulty in diagnosis. In our retrospective pilot study, we assessed whether dogs with evidence of portal hypertension and absence of pancreatitis on pancreatic histology have increases in canine pancreatic lipase immunoreactivity (cPLI) and 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester (DGGR) lipase. We included dogs that had been presented between 2008 and 2019 if they had normal pancreatic histology, histologically confirmed hepatopathy, and if canine pancreas-specific lipase (Spec cPL; Idexx) or DGGR lipase had been measured. Only dogs with portal hypertension were included. Six dogs fulfilled the inclusion criteria. Four of 6 and 2 of 6 dogs had Spec cPL and DGGR lipase exceeding the upper reference limit, respectively. From the 4 dogs with increased Spec cPL, 2 had concentrations of 200-400 µg/L and 2 had concentrations ≥ 400 µg/L. Our results suggest that canine portal hypertension might lead to increased Spec cPL and DGGR lipase values in the absence of pancreatitis on histology. Until more evidence in a larger number of dogs with portal hypertension is available, both tests should be interpreted cautiously in the presence of portal hypertension.

Effect of prednisolone therapy on serum levels of 1,2-O-dilauryl-rac-glycero glutaric acid-(6'-methylresorufin) ester lipase in dogs

BACKGROUND

Activity of 1,2-O-dilauryl-rac-glycero glutaric acid-(6'-methylresorufin) ester (DGGR) lipase in serum shows good agreement with pancreatic lipase (cPL) in dogs. Although prednisolone therapy does not seem to affect serum cPL concentration, its influence on DGGR lipase is unclear.

OBJECTIVES

The aim of the study was to evaluate the effect of prednisolone therapy on DGGR lipase serum activity in dogs.

ANIMALS

Thirty-four dogs were used, of which 17 dogs received prednisolone (study group) and 17 healthy dogs did not receive treatment.

METHODS

A prospective cohort study measured DGGR lipase activity in both groups at 3 time points: T0, T1, and T2, corresponding to days 0, 7-10, and 21-30, respectively. Dogs from study group presented a medical reason that justified the use of prednisolone for at least 3 weeks. Initial prednisolone dose was .5-2.0 mg/kg/day PO with a reduction at T1 to a final dose that was maintained until T2. DGGR lipase activity >160 U/L was defined as clinically relevant.

RESULTS

In the study group, DGGR lipase activity increased significantly from T0 to T1 (P = .02) and decreased significantly from T1 to T2 (P = .02). Median DGGR activity at each time point (T0, T1, and T2) was 24.74 (14.45-31.48), 36.82 (23.8-80.16), and 29.52 (15.91-48.48) U/L, respectively. In the control group, no significant changes were observed over time (P = .93). The DGGR lipase activity and prednisolone doses were not correlated for both T0-T1 (r_s = .371, P = .14) and T1-T2 (r_s = 0.390, P = .12).

CONCLUSION AND CLINICAL IMPORTANCE

DGGR lipase activity was affected by prednisolone administered orally in dogs. However, this variation was not clinically important as values remained below the relevant upper limit.

The 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester (DGGR) lipase assay in cats and dogs is not specific for pancreatic lipase

BACKGROUND

The measurement of pancreatic lipase is important for the diagnosis of feline and canine pancreatitis. Recent studies have claimed that lipase assays using the 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester (DGGR) as a substrate are more specific for measuring pancreatic lipase than traditional lipase assays. However, the analytical specificity of this assay for pancreatic lipase has not been demonstrated.

OBJECTIVES

We aimed to determine whether hepatic and/or lipoprotein lipases can interfere with the DGGR-based assay results in cats and dogs. We, therefore, compared plasma lipase activities measured using DGGR-based and pancreatic lipase immunoreactivity (PLI) assays before and after administering heparin, known to cause the release of hepatic and lipoprotein lipases, in cats and dogs.

METHODS

Heparin was administered in six cats and six dogs. Blood was collected at baseline and 10, 20, 30, 60, and 120 minutes after heparin administration. Lipase activity was measured using a DGGR-based assay, and PLI concentrations were measured using the Spec fPL and cPL assays for cats and dogs, respectively.

RESULTS

Plasma lipase activities, as measured using the DGGR-based assay, increased significantly 10 minutes after heparin administration in both cats (P = .003) and dogs (P = .006) and returned to baseline by 120 minutes. In contrast, PLI concentrations showed no significant changes after heparin administration.

CONCLUSIONS

DGGR is not only hydrolyzed by pancreatic lipase but also by hepatic lipase, lipoprotein lipase, or both, in cats and dogs. Since these extrapancreatic lipases are also naturally present in cats and dogs, they could contribute to the lack of analytical specificity for the DGGR-based assays.

Acute on chronic kidney disease in dogs: Etiology, clinical and clinicopathologic findings, prognostic markers, and survival

BACKGROUND

Chronic kidney disease (CKD) and acute exacerbation of CKD (ACKD) are common in dogs.

OBJECTIVE

To characterize the etiology, clinical and laboratory findings, and short- and long-term prognosis of dogs with ACKD.

ANIMALS

One hundred dogs with ACKD.

METHODS

Medical records of dogs diagnosed with ACKD admitted to a veterinary teaching hospital were retrospectively reviewed.

RESULTS

The most common clinical signs included anorexia (84%), lethargy (77%), vomiting (55%) and diarrhea (37%). Presumptive etiology included inflammatory causes (30%), pyelonephritis (15%), ischemic causes (7%), other (3%), or unknown (45%). Median hospitalization time was 5 days (range, 2-29 days) and was significantly longer in survivors (6 days; range, 2-29 days) compared with nonsurvivors (4 days; range, 2-20 days; P < .001). Mortality rate was 35%. International Renal Interest Society (IRIS) acute kidney injury (AKI) grade at presentation was associated (P = .009) with short-term survival, but presumptive etiology was not (P = .46). On multivariable analysis; respiratory rate (P = .01), creatine kinase (CK) activity (P = .005) and serum creatinine concentration (SCR; P = .04) at presentation were associated with short-term outcome. Median survival time of dogs discharged was 105 days (95% confidence interval [CI], 25-184), with 35 and 8 dogs surviving up to 6 and 12 months, respectively. Presumptive etiology (P = .16) and SCR (P = .59) at discharge were not predictors of long-term survival.

CONCLUSION AND CLINICAL IMPORTANCE

Short-term outcome of dogs with ACKD is comparable to those with AKI but long-term prognosis is guarded. The IRIS AKI grade at presentation is a prognostic indicator of short-term outcome.