Can measurement of glucose levels in blood and peritoneal fluid be used to diagnose septic peritonitis in dogs?

TL;DR

Measuring glucose levels in blood and peritoneal fluid can help diagnose septic peritonitis in dogs, but it should be used alongside other diagnostic methods.

Contribution

The study identifies specific glucose level thresholds for diagnosing septic peritonitis in dogs using point-of-care and biochemistry methods.

Findings

Blood plasma glucose >2.1 mmol/L higher than peritoneal fluid glucose indicates septic peritonitis using a POC glucometer.

Whole blood glucose >1.1 mmol/L higher than peritoneal fluid glucose indicates septic peritonitis using a biochemistry analyser.

Glucose measurements are useful but not 100% accurate and should be combined with other diagnostic tests.

Abstract

PICO question

Can the measurement of blood and peritoneal fluid effusion glucose levels be used to accurately diagnose septic peritonitis in dogs when compared to cytology and bacterial culture?

Clinical bottom line

Category of research question

Diagnosis

The number and type of study designs reviewed

Three papers were critically reviewed, all of which were diagnostic test evaluation studies

Strength of evidence

Moderate

Outcomes reported

Glucose measurements can be used to diagnose septic peritonitis when the blood plasma glucose level is >2.1 mmol/L higher than that of the peritoneal fluid glucose when using a veterinary point of care (POC) glucometer. If using a biochemistry analyser, a whole blood glucose >1.1 mmol/L higher than that of the peritoneal fluid can be used to diagnose septic peritonitis. This is only relevant when the peritoneal fluid is collected by abdominocentesis and not in a postoperative period

Conclusion

At present, there is moderate evidence that glucose measurements are useful as a patient side test for the diagnosis of septic peritonitis and are especially useful in cases where intracellular bacteria cannot be identified on cytology. However, despite the so far promising accuracy results, the cut-offs reported are quite variable and overall, there is not a single diagnostic test that is 100% sensitive and specific in repeated studies. Therefore, the results of the glucose measurements should be evaluated alongside other biomarker testing, imaging modalities and the clinical presentation of the patient. Glucose measurements cannot currently replace culture / sensitivity and cytology as the gold standard for the diagnosis of septic peritonitis