A prospective study of soft-tissue ultrasonography in sickle cell disease patients with suspected osteomyelitis

AIM: A prospective study was done to assess the accuracy of soft tissue ult rasonography in patients with sickle cell disease (SCD) presenting with sus pected osteomyelitis. MATERIALS AM) METHODS: Thirty-one SCD patients had soft tissue ultrasonogra phy on 38 occasions (18 men, 13 women; mean age 8.2 years). The initial ult rasonographic signs and diagnosis were compared with the final clinical dia gnosis, which was based on clinical progress and scintigraphy. RESULT: The overall sensitivity of ultrasound in diagnosing osteomyelitis w as 74% with a specificity of 63%. The principal ultrasonographic finding of subperiosteal fluid was present in 14 (74%) patients with osteomyelitis an d seven (37%) patients without infection, A finding of a subperiosteal flui d depth of 4 mm or more was significantly associated with osteomyelitis (P < 0.01). CONCLUSION: Ultrasonography should be the initial investigation in SCD pati ents if osteomyelitis is suspected clinically, In such a clinical setting, a finding of 4 mm depth or more of subperiosteal fluid appears to be diagno stic. Previous statements that the presence of any subperiosteal fluid indi cates infection are shown to be inaccurate. Patients with less than 4 mm of subperiosteal fluid require further imaging or aspiration to establish the diagnosis of osteomyelitis. (C) 2000 The Royal College of Radiologists.