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We read with interest the letter from Clarke and Ioannou regarding our study. Although we acknowledge the risk of confounding, given the retrospective nature of our manuscript, we feel it is highly unlikely that these factors had an impact on our results. Although hypothermia has been associated with QTc prolongation,1Aslam A.F. Aslam A.K. Vasavada B.C. Khan I.A. Hypothermia: evaluation, electrocardiographic manifestations, and management.Am J Med. 2006; 119: 297-301Abstract Full Text Full Text PDF PubMed Scopus (105) Google Scholar infection is a rare cause of diabetic ketoacidosis (DKA) in developed countries and accounts for only 15% of cases of DKA.2Umpierrez G. Korytkowski M. Diabetic emergencies—ketoacidosis, hyperglycaemic hyperosmolar state and hypoglycaemia.Nat Rev Endocrinol. 2016; 12: 222-232Crossref PubMed Scopus (193) Google Scholar Hypothermia could not be attributed as a cause of QTc prolongation in our cohort, as none of the 96 patients had a temperature <35°C during their course of illness on further review of the data. The authors acknowledge the association between type 1 diabetes mellitus and thyroid disorders; however, DKA has been shown to be associated with sick euthyroid syndrome and a normal thyroid-stimulating hormone.3Rashidi H. Ghaderian S.B. Latifi S.M. Hoseini F. Impact of diabetic ketoacidosis on thyroid function tests in type 1 diabetes mellitus patients.Diabetes Metab Syndr. 2017; 11: S57-S59Crossref PubMed Scopus (12) Google Scholar It is difficult to imagine a consistent relationship between DKA severity and thyroid-stimulating hormone elevation that could drive the association with QTc prolongation. Cerebral edema occurs in <1% of cases of DKA,4Bohn D. Daneman D. Diabetic ketoacidosis and cerebral edema.Curr Opin Pediatr. 2002; 14: 287-291Crossref PubMed Scopus (51) Google Scholar so this rare potential confounder was not specifically assessed. Our data (Table I) did demonstrate a statistically significant heart rate elevation by severity of DKA, which would challenge the assertion that increased intracranial pressure had a clinical impact, especially in the severe DKA group. Furthermore, the association between elevated intracranial pressure and QTc prolongation has mostly been observed in cases of subarachnoid hemorrhage.5Gregory T. Smith M. Cardiovascular complications of brain injury.Cont Educ Anaesth Crit Care Pain. 2012; 12: 67-71Abstract Full Text Full Text PDF Scopus (31) Google Scholar We would again like to thank our colleagues for their interest in our article. Could the QTc prolongation seen in diabetic ketoacidosis be due to more than just a raised anion gap?The Journal of PediatricsVol. 231PreviewPerez et al1 demonstrated that nearly one-third of patients presenting with diabetic ketoacidosis (DKA) had QTc prolongation. The authors demonstrated a significant correlation between the QTc and anion gap and, therefore, hypothesized that the QTc prolongation seen was secondary to an elevated anion gap and metabolic acidosis. Full-Text PDF