Clinical variables and Staphylococcus aureus virulence factors associated with venous thromboembolism in children

Thromb Res. 2016 Feb;138:69-73. doi: 10.1016/j.thromres.2015.11.029. Epub 2015 Nov 25.

Abstract

Objectives: Children with Staphylococcus aureus (SA) bacteremia risk developing venous thromboembolism (VTE). We sought to identify clinical variables and bacterial virulence factors associated with VTE in SA bacteremia.

Study design: This is a single-institution retrospective study of 229 children with SA bacteremia hospitalized from 2005 to 2008. Clinical data were abstracted from patient charts. Two-hundred three SA isolates were analyzed by polymerase chain reaction. The Pediatric Health Information System (PHIS) database was queried to identify subjects with a central venous line (CVL) or complex chronic conditions (CCC). Logistic regression analysis was employed to determine which factors most greatly influenced VTE.

Results: VTE was present in 9.2% (n=21/229). Superficial thrombi were excluded. Mortality was greater in patients with VTE [24% vs. 6% (p=0.016)]. Among SA isolates available for virulence testing, the majority (70%; n=139) were methicillin-sensitive SA (MSSA). Methicillin-resistant SA (MRSA) infection was associated with VTE (p=0.01). The most common sites of thrombosis were extremity deep vein (58%; n=14/24), head/neck (29%; n=7), and visceral (13%; n=3). One subject had a pulmonary embolism. The presence of a CVL or a CCC was not associated with VTE. Independent predictors of VTE were C-reactive protein (CRP)≥20mg/dl [OR 4.2, 95% CI 1.16-15.25] and hemoglobin nadir ≤9g/dl [OR 5.2, 95% CI 1.3-20.64].

Conclusions: In addition to MRSA infection, CRP≥20mg/dl and hemoglobin nadir ≤9g/dl were associated with VTE in SA bacteremia. These factors may serve as markers for increased risk of VTE with invasive SA disease.

Keywords: Anemia; Bacteremia; CRP; Thrombosis; VTE; Virulence factors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Bacteremia / blood
  • Bacteremia / complications*
  • Bacteremia / microbiology
  • C-Reactive Protein / analysis
  • Child
  • Child, Preschool
  • Female
  • Hemoglobins / analysis
  • Humans
  • Male
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification
  • Retrospective Studies
  • Risk Factors
  • Staphylococcal Infections / blood
  • Staphylococcal Infections / complications*
  • Staphylococcal Infections / microbiology
  • Staphylococcus aureus / isolation & purification*
  • Venous Thromboembolism / blood
  • Venous Thromboembolism / complications*
  • Venous Thromboembolism / microbiology*
  • Virulence Factors / analysis

Substances

  • Hemoglobins
  • Virulence Factors
  • C-Reactive Protein