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.