Abstract
Aim
Differentiation between bone infarction and bone infection in sickle cell disease has traditionally been difficult, even with modern imaging techniques, and widespread antibiotic use is common. Early differentiation between the two conditions would enable more appropriate targeting of radiological investigations, antibiotics and surgery, and avoid un-necessary antibiotic usage.
Method
At our tertiary paediatric sickle cell centre, we have developed a sequencing protocol to be able to accurately differentiate between infection and infarction in sickle cell children using Magnetic Resonance (MR) Imaging. We have undertaken a preliminary retrospective study to analyse clinical and laboratory parameters in these children to see whether earlier differentiation prior to MR imaging is possible.
Results
We identified 52 episodes in 27 patients of bony pain in sickle cell children between 2006 and 2012. In 30 episodes in 27 patients, the MR sequences used allowed accurate determination of pathology, diagnosing infarction in 19 episodes in 17 patients, and infection in 8 episodes in 7 patients. The remainder showed no evidence of acute infarction or infection despite pain. As a general trend, admission white cell counts were higher in the infection group, with a temperature on admission also being more likely. There was no significant difference in CRP or platelet count between the infarction and infection groups.
Conclusion
From a small retrospective study it may be possible to identify factors making infection as a cause of bone pain in sickle cell disease more likely, enabling better targeting of urgent MR imaging and surgery and preventing un-necessary antibiotic usage. A larger, prospective study is required and is currently underway.