A review of capillary β-hydroxybutyrate cut-off levels for the exclusion and identification of diabetic ketoacidosis

Abstract

Aims/Introduction: Diabetic ketoacidosis (DKA) is an acute, life-threatening emergency that can arise as a complication of diabetes mellitus. We sought to examine the literature regarding capillary β-OHB testing levels that can inform cut-offs and help clinicians to safely and effectively exclude or identify DKA. Materials and Methods: For this narrative review with a systematic approach, MEDLINE, Embase, and Emcare databases were searched for primary studies. Included studies described capillary β-OHB levels in relation to suspected DKA, for populations aged ≥16 years. Exclusion criteria were non-English language, animal studies or case reports, and/or exclusive focus on serum β-OHB. Results: Of the 1,177 records identified, 11 studies met the criteria for data extraction. To exclude DKA in patients with hyperglycemia, capillary β-OHB cut-off values of <1.0 mmol/L and <1.5 mmol/L were most recommended. A capillary β-OHB level >3.0 mmol/L exhibited high sensitivity and specificity in detecting DKA and may be used in identifying cases of DKA. Conclusions: Capillary testing can reliably detect β-OHB levels within the DKA diagnostic threshold. While a capillary β-OHB threshold of <1.5 mmol/L may help clinicians exclude DKA, a capillary β-OHB level >3.0 mmol/L showed high sensitivity and specificity in detecting DKA. Future studies are needed to validate proposed cut-offs and examine the utility of capillary β-OHB testing in prehospital settings.