Chronic Recurrent Multifocal Osteomyelitis

Abstract

Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory bone disease occurring primarily in children and adolescents. Episodes of systemic inflammation occur due to immune dysregulation without autoantibodies, pathogens or antigen-specific T cells. CRMO is characterised by the insidious onset of pain with swelling and tenderness over the affected bones. Clavicular involvement was the classical description; however, the metaphyses and epiphyses of long bones are frequently affected. Lesions may occur in any bone, including vertebrae. Characteristic imaging includes bone oedema, lytic areas, periosteal reaction and soft tissue reaction. Biopsies from affected areas display polymorphonuclear leucocytes with osteoclasts and necrosis in the early stages. Subsequently, lymphocytes and plasma cells predominate followed by fibrosis and signs of reactive new bone forming around the inflammation. Diagnosis is facilitated by the use of STIR MRI scanning, potentially obviating the need for biopsy and unnecessary long-term antibiotics due to incorrect diagnosis. Treatment options include non-steroidal anti-inflammatory drugs and bisphosphonates. Biologics have been tried in resistant cases with promising initial results. Gene identification has not proved easy although research in this area continues. Early descriptions of the disease suggested a benign course; however, longer-term follow up shows that it can cause significant morbidity and longer-term disability. Although it has always been thought of as very rare, the prevalence is likely to be vastly underestimated due to poor recognition of the disease.

Chronic recurrent multifocal osteomyelitis beginning with a solitary lesion of the ilium

“…In general, the occurrence of multifocal bone pain is suggestive of CRMO, however investigations must be performed to rule out other major differential considerations, such as infectious osteomyelitis and bone tumors [9]. The lesions are typically located in the metaphyses of tubular bones, followed by the clavicle and spine [6, 16, 17]. It is unusual for CRMO to begin in a flat pelvic bone such as the ilium; although an initial presentation in the vertebra has been previously reported in children and adults [18, 19].…”

An Unusual Association of Chronic Recurrent Multifocal Osteomyelitis, Pyoderma Gangrenosum, and Takayasu Arteritis

“…Chronic recurrent multifocal osteomyelitis (CRMO) is hypothesized to be an autoimmune disorder because of its association with multiple autoimmune diseases, including inflammatory bowel disease, psoriasis, acne, pustulosis, Sweet syndrome, dyserythropoietic anemia, pyoderma gangrenosum (PG), sclerosing cholangitis, inflammatory arthritis, Still disease, Takayasu arteritis (TA), Ollier disease, and dermatomyositis 1,2 .…”

Syndromes with chronic non-bacterial osteomyelitis in the spine

“…Chronic recurrent multifocal osteomyelitis was described primarily in children and adolescents [ 18 ]. Mean age at CRMO onset is approximately 10 years, with a range of 4–14 years, mean disease duration is approximately 5 years, and the mean number of flares per patient was approximately 6 [ 19 ].…”