Calcium and magnesium abnormalities in dogs with parvoviral enteritis

Abstract

Canine parvoviral enteritis (CPE) is a common cause of acute, life-threatening enteritis in young dogs. While gastrointestinal disturbances and immunosuppression are the most recognised sequelae of CPE, a less apparent systemic inflammatory response syndrome (SIRS) also develops in many dogs. Calcium and magnesium abnormalities are increasingly recognised in the critical care setting. Ionised hypocalcaemia (iHypoCa) is well documented among humans with sepsis, and it has been associated with an increased duration in hospital stay in dogs with CPE, as well as mortality in dogs evaluated in an emergency room or intensive care setting. Moreover, critical illness has been identified as the most common cause of iHypoCa in dogs. Hypomagnesaemia is a common occurrence in critically ill people and animals, but it has not been associated with outcome in dogs infected with CPE. A significant correlation has been found between serum calcium and magnesium concentrations in dogs with hypomagnesaemia. The objective of this study were a) to determine the association between the development of iHypoCa and total hypomagnesaemia, and sepsis, and b) to investigate whether ionised calcium (iCa) or total magnesium (tMg) is associated with mortality in dogs with CPE. Sixty-four client-owned dogs with CPE were enrolled in this prospective cohort study. Serum iCa and tMg were measured daily from admission until death or discharge. Fifteen healthy client-owned dogs were used as controls. Mean iCa concentrations of the CPE group on admission were significantly lower compared to the control group (1.35 mmol/L vs 1.52 mmol/L). Ionised calcium concentrations of non-survivors were significantly higher compared to survivors on day two, but not on any other days. Dogs that were hypercalcaemic on day two were also significantly more likely to die than normocalcaemic dogs after adjusting for multiple comparisons (OR = 10.7; 95% CI: 1.7-71). Ionised calcium was not associated with the development of sepsis on any day. In contrast, mean admission tMg concentrations of the CPE group were significantly higher compared to the control group (0.72 mmol/L vs 0.63 mmol/L). However, tMg concentrations were not significantly different between survivors and non-survivors, nor were they associated with the development of sepsis on any day. In summary, dogs with CPE had lower iCa and higher tMg compared to healthy dogs on admission, and the iCa concentrations of non-survivors were significantly higher on day two compared to survivors. Results of this study provide insight into calcium homeostasis in critically ill young dogs with CPE.