Introduction:
Venous thromboembolism (VTE) is a rare but serious event in pediatrics that can cause significant morbidity and mortality. The estimated overall annual VTE incidence is approximately ten per 100 000 children, with VTE diagnosed more commonly in hospitalized children, with a frequency of greater than 50 per 10 000 [1-4]. Infants and adolescents are most often affected by VTE, and central venous catheters (CVC) have been estimated to be involved in up to 70% of pediatric VTE [2,4]. It has also been well-established that most pediatric VTE occur in patients with an underlying chronic medical condition or an acquired risk factor [2,3].
Diabetes mellitus (DM) type 1 is a chronic medical condition characterized by immune-mediated pancreatic β-cell destruction, resulting in insulin deficiency. The incidence is increasing amongst all pediatric ages, but particularly in children under five years of age [5]. Diabetic ketoacidosis (DKA) is a serious complication of DM associated with ketosis, acidosis, and hyperglycemia [6]. Endothelial damage as well as hemostatic changes have been described in patients with DKA, including increased Factor VIII levels, increased fibrinogen, thrombocytosis, decreased protein C activity, and increased von Willebrand factor [7-9]. These hemostatic changes suggest enhanced coagulation potential and a prothrombotic state [10-14].
The management of a child with DKA can necessitate CVC placement to ensure appropriate therapeutic interventions are provided efficiently. CVC placement has been reported in up to 5% of children with DKA, but DKA management guidelines have recommended avoidance of CVC use implying the actual incidence of CVC placement for DKA management in children today could be less [15-17]. Children with DKA, particularly those under three years of age, undergoing CVC placement are at increased risk for VTE development (approximately 50% VTE incidence), even more so than similarly aged children with CVC placement for a reason other than DKA [15, 18, 19]. Although young age has been associated with increased CVC-associated VTE in DKA, supporting evidence in the literature is weak. Also, other predictive indicators, including laboratory investigations, have not been evaluated to suggest which children with DKA undergoing CVC placement might be at higher risk for developing CVC-associated VTE.
In this report, DKA admissions to our facility over a ten year period were reviewed for patients aged less than five years old. Patients older than five years were not included because a preliminary analysis revealed that no CVC were placed in this population. We hypothesized that children with DKA would have a higher CVC-associated VTE incidence than all other patient groups and that young age would remain a risk factor for CVC-associated VTE in DKA.