Diagnostic dilemma in sicklers with acute bone crisis: role of subperiosteal fluid collection on MRI in resolving this issue.

OBJECTIVES To establish MRI criteria to diagnose early osteomyelitis in sickle cell disease patients with acute bone crisis and to differentiate it from normally occurring ischaemic changes in these patients. METHODS MRI study with and without Gadolinium contrast was carried out in 59 sickle cell disease patients who presented with acute bone crisis from August 2007 to July 2008, and had clinical suspicion of osteomyelitis. We studied the ability of MRI especially the presence of subperiosteal fluid, for the early diagnosis of osteomyelitis and its differentiation from ischaemic changes in these patients. RESULTS Depending on MRI diagnostic criteria, we diagnosed 32 cases for osteomyelitis. In 26 patients diagnosis was confirmed microbiologically while 6 patients were treated on clinico radiological basis which showed marked improvement on follow up. Five patients with osteomyelitis had established MR features of osteomyelitis while in 27 cases the diagnosis was made on the basis of presence of subperiosteal fluid. CONCLUSION Early osteomyelitis is a challenging diagnosis clinically and radiologically in patients with sickle cell disease, which can be diagnosed on M.R.I if special emphasis is put on subperiosteal fluid collection.