[Chronic recurrent multifocal osteomyelitis with interstitial myositis]

Myositis, Osteomyelitis and a Parasymphyseal Stress Fracture in a Paediatric Patient

The limping child and painful hip are common presentations in many paediatric emergency units. Typically caused by mild self-limiting events, less commonly, they may be implicated in one of a group of inflammatory myopathies, or myositis. Diagnosis of this condition can be extremely difficult, and is aided by thorough clinical assessment, radiological imaging, and extensive blood serum testing. Myositis with associated osteomyelitis and a pathological fracture is an incredibly rare finding, described in this case report in a seven-year-old child. 

Adult-onset Chronic Recurrent Multifocal Osteomyelitis with High Intensity of Muscles Detected by Magnetic Resonance Imaging, Successfully Controlled with Tocilizumab

Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory bone disorder that generally occurs in children and predominantly affects the long bones with marginal sclerosis. We herein report two cases of adult-onset CRMO involving the tibial diaphysis bilaterally, accompanied by polyarthritis. Magnetic resonance imaging (MRI) showed both tibial osteomyelitis and high intensity of the extensive lower leg muscles. Anti-interleukin-6 therapy with tocilizumab (TCZ) effectively controlled symptoms and inflammatory markers in both patients. High intensity of the lower leg muscles detected by MRI also improved. These cases demonstrate that CRMO should be included in the differential diagnosis of adult patients with bone pain, inflammation, and high intensity of the muscles detected by MRI. TCZ may therefore be an effective therapy for muscle inflammation of CRMO.