**7. Clinical features**

Several studies have suggested that children with DVT- associated osteomyelitis demonstrate a more severe clinical course when compared to children who do not have deep venous thrombosis.3,5,6,8,9,10,11 Specifically, children with DVT are more likely to be admitted to the intensive care unit (ICU), require more surgical procedures, and have a longer hospitalization than their counterparts who do not have DVT but who do have similar forms of musculoskeletal infection.2,5,9,10,13,17,19 One study found that children with DVT required an average of 2.6 surgical procedures per child and had a mean duration of hospitalization of 30.6 days, compared to children without DVT who underwent an average of 0.9 surgical procedures per child and were hospitalized an average of 9.5 days.9 The same study determined that children with DVT presented with higher inflammatory indices in comparison to children who did not have DVT.9 The mean C-reactive protein (CRP) in children with DVT was 16.9 mg/dL , compared with only 6.8 mg/dL in children without DVT.9 While intuitively it might be thought that children with DVT would have a delay in clinical presentation to a healthcare facility, the authors found that there was in fact a

Deep Venous Thrombosis in Children with Musculoskeletal Infection 75

children should undergo screening with non-invasive Doppler ultrasound evaluation of the extremities in the region of the musculoskeletal infection to look for DVT. If the ability to assess the PVL status of the organism is present within any institution, then this should be considered whenever *Staphylococcus aureus* is isolated from bone, joint, or muscle specimens. While stratification of the relative risk of DVT may increase the awareness of the treating physician of the child's potential for DVT, it is important not to overlook the rare cases of DVT that might occur in children who fall outside of this risk profile, such as those with upper extremity locations of infection, infection types other than osteomyelitis, causative organisms other than *Staphylococcus aureus*, or age under 4 years. Whenever the clinical

Children with DVT and osteomyelitis can be effectively managed with low molecular weight heparin. Resolution of the DVT occurs at an average of ten to twelve weeks.5,9 Follow-up imaging is helpful to ensure resolution of the DVT. In cases refractory to low molecular-weight heparin, consideration may be given to placement of an intravascular filter. Warfarin is also an option, but requires additional effort in managing the prothrombin

Because children with DVT and osteomyelitis may require repeat surgical procedures, care must be taken to appropriately withhold and resume the anticoagulant therapy around

Pediatric musculoskleletal infection is associated with the risk for DVT. Risk factors include: osteomyelitis; lower extremity location of infection; *Staphylococcus aureus*, particularly MRSA, as the causative organism; age greater than 4 years; markedly elevated inflammatory indices; severe clinical illness often requiring intensive care unit admission, intubation, or inotrope support; and pulmonary involvement with infiltrates, pneumonia, or septic pulmonary emboli. A high index of suspicion should be maintained when risk factors are present and appropriate screening imaging should be obtained. One study demonstrated a 40% rate of DVT when the child was greater than 8 years of age with positive cultures for MRSA and an initial CRP of greater than 6 mg/dL.9 Consideration may be given to evaluating for the presence of PVL within the bacterial genetics to help further stratify the risk of DVT. Whenever DVT is identified, appropriate treatment should be administered in a timely manner and the child should be monitored until the point of resolution. The

[1] Newgard C. D, Inkelis S. H, & Mink R. (2002). Septic thromboembolism from unrecognized deep venous thrombosis in a child. *Pediatric Emergency Care, 18*(3), 192-196. [2] Walsh Stewart, & Philips Fredrick. (2002). Deep vein thrombosis associated withpediatric musculoskeletal sepsis. *Journal of Pediatrics Orthopedics, 22*, 329-332. [3] Martinez-Aguilar G, Avalos-Mishaan A, Hulten K, Hammerman W, Mason E O, &

Kaplan S L. (2004). Community acquired methicillin-resistant and methicillin-

suspicion of DVT exists, supplemental imaging should be considered.

time (PT) and international normalized ratio (INR) effectively.

periods of surgery to avoid bleeding complications.

**11. Treatment** 

**12. Conclusions** 

anticipated outcome is good.

**13. References** 

shorter duration between the onset of admission for children with DVT compared to those without. (5.6 days versus 14.4 days).9 This lends further support to the possibility that children with musculoskeletal infection and DVT have a more abrupt onset and rapid clinical decline to the point where medical attention is sought. Pulmonary involvement with a variety of manifestations including pneumonia, septic pulmonary emboli, cavitary pneumatoceles, empyema, and various infiltrates was recorded in 36 of the 58 children with DVT (62.1%).1,2,4-7,9-11,13-19
