Nonbacterial osteitis: a clinical, histopathological, and imaging study with a proposal for protocol-based management of patients with this diagnosis

Background. Nonbacterial osteitis (NBO), a term referring to sterile bone lesions with nonspecifi c histopathological features of inflammation, may be either unifocal or multifocal, acute (<= 6 months) or chronic, and recurrent. Only when the condition is chronic, recurrent, and multifocal is it appropriate to use the term chronic recurrent multifocal osteomyelitis (CRMO). We present our clinical experience as the largest reported series of children with NBO to date. Methods. We report a retrospective clinical, histopathological, and radiological study of 41 children with nonbacterial osteitis. Results. Of 41 children (2-16 years of age) diagnosed with NBO in our institution over the last 6 years, 21 (51%) had recurrent disease and 18 (44%) had multifocal disease. The most common bones affected were the clavicle, femur, and tibia (in order of decreasing prevalence) accounting for 44 (63%) of a total of 70 lesions. Only one individual had SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, osteitis) and no other patients had evidence of bowel or skin disease. In the absence of evidence for an infective etiology, we recommend nonsteroidal anti-inflammatory agents as the first-line therapy and bisphosphonates only in cases of resistant disease. Conclusions. On the basis of our findings, we propose using a patient questionnaire and protocol for investigating and managing patients who present with NBO to orthopedic surgeons. We predict that this will benefit patients with this disorder by improving our knowledge of the presenting signs and symptoms and related disorders, rationalizing the therapeutic approach, and allowing us to learn about the natural history of the disease.