Ultrasonography: can it differentiate between vasoocclusive crisis and acute osteomyelitis in sickle cell disease?

We prospectively evaluated the results of ultrasonography in 53 patients of sickle cell disease suspected to have vasoocclusive crisis/acute hematogenous osteomyelitis. The average age was 8.4 +/- 3.40 years (range, 1-14). Twenty-six children were boys and 27 were girls. Seventeen (32%) patients had ultrasonographic changes that suggested acute osteomyelitis. The minimal white cell count was 7,200/mm3, and maximal, 9,900/mm3 (mean, 8,190/mm3) in uninfected patients and in 17 patients, the mean was 10,300/mm3 (7,200-13,600/mm3). The mean erythrocyte sedimentation rate in uninfected patients was 32 for the first hour (19-36 mm), and in infected patients, it was 43 for the first hour (35-38 mm). Pus culture was positive in all infected patients, and the infective organism was Salmonella enteriditis in eight, staphylococcal species in six (S. aureus in four and S. epidermidis in two), and Streptococcus species 1 and 2, anaerobic streptococci. All patients with vasoocclusive crisis were treated with analgesics and intravenous fluids and did not require any further treatment. In patients with acute osteomyelitis, the treatment was incision, drainage and drilling of bone, and antibiotic therapy. We conclude that ultrasonography clearly and decisively differentiated acute osteomyelitis from vasoocclusive crisis in patients with sickle cell disease.