Pancreatitis in dogs and the predictive role of C-reactive protein

Pancreatitis in dogs: introduction

Pancreatitis in dogs can be broadly classified as acute, recurrent or chronic. The histological characteristics of acute pancreatitis include pancreatic oedema with possible necrosis, a variety of mononuclear and polymorphonuclear cell infiltrates, and peripancreatic fat necrosis and thrombosis. Chronic pancreatitis is characterised by fibrosis and low-grade mononuclear inflammation and may be a sequela of acute pancreatitis or a subclinical process that may manifest as diabetes or exocrine pancreatic insufficiency.

Pancreatitis in dogs can be further classified as mild or severe, non-fatal or fatal according to its effect on the patient and the presence of sequelae, so there is a tendency to identify mild acute pancreatitis with pancreatic oedema, and severe or fatal pancreatitis with pancreatic necrosis.

Acute pancreatitis (AP) in dogs: significance

AP is a common disease in dogs. Although most cases of pancreatitis are moderate and self-limiting, some develop potentially fatal systemic complications. The mortality rates reported for severe acute pancreatitis range from 27 to 42%. In humans, we know that the degree of necrosis and bacterial infection are both determinants of mortality, so there is particular interest in the search for biomarkers that identify the risk of pancreatic necrosis.

Predicting mortality: C-reactive protein (CRP)

CRP is an acute phase reactant synthesised by the liver in response to inflammation, infection and tissue destruction. Its synthesis is stimulated by other inflammatory factors, such as TNF, IL-1 and IL-6. Due to the simplicity and low cost of CRP testing, it has become the gold standard as a plasma marker of disease severity.

Although there are no published studies regarding plasma CRP concentrations in dogs with acute pancreatitis, a number of recent abstracts support the hypothesis that CRP levels have a prognostic value, with significantly high levels detected in dogs with severe (necrotic) pancreatitis compared to those with moderate (interstitial) pancreatitis.

On this basis, a study¹ was conducted to analyse the serum CRP concentrations in dogs with pancreatitis compared to a control group. Where possible, the serum CRP concentrations were measured on the day of diagnosis (Day 1), Day 3 and Day 5.

The group of 16 dogs with acute pancreatitis had elevated serum CRP levels. In the 7 dogs with CRP measured on all three days, the mean CRP concentration decreased from the day of diagnosis to the measurement taken on Day 5. However, they were still significantly higher than the control group levels on Day 5. The mean hospital stay in the subject group was 7.5 ± 3.2 days. Of the 16 dogs with acute pancreatitis, 14 were discharged and two were euthanised.

Conclusions

This study found CRP concentrations to be significantly higher in dogs with AP compared to the controls. The concentration decreased significantly over time in the 7 dogs with measurements taken at all three time points, but it remained significantly higher than the control group, even on Day 5. All these subjects showed clinical improvement and were discharged from hospital.

Thus, CRP concentrations in dogs with pancreatitis may be useful for monitoring its clinical progression and the treatment response.

Further studies with more cases of varying severity are needed to determine the utility of CRP as a predictor of the severity of acute pancreatitis in dogs.

1. Jennifer L. Holm et al. C-reactive protein concentrations in canine acute pancreatitis. Journal of Veterinary Emergency and Critical Care 14 (3) 2004, pp.183–186.