Chronic recurrent multifocal osteomyelitis: a rare skeletal disorder

Radiographic changes of chronic recurrent multifocal osteomyelitis that persisted into adulthood

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare non-infectious autoinflammatory disorder typically seen in young women. We describe the case of a young man who presented at 13 years of age with pain in the tibia, humerus, clavicle and hip. Worsening of the condition through clinical presentation and radiographic imaging was observed over 10 years. Radiographic imaging initially showed some sclerotic changes, but worsened to osteolytic lesions of the proximal tibia, elevation of the lateral cortex and thickening of the anterior cortex. Bone biopsy of his right anterior proximal tibia showed no infection or neoplasia. But, laboratory results showed elevation of inflammatory markers such as erythrocyte sedimentation rate or C-reactive protein. The patient was diagnosed with CRMO and treated with antibiotics for suspicion of chronic bacterial osteomyelitis. Chronic bone pain, abnormal imaging and elevation of inflammatory markers suggesting that chronic bacterial osteomyelitis can lead to difficulties with the diagnosis of CRMO.

A complicated path to the CRMO diagnosis - case of a 9 year old girl whose story comes full circle

Background

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare idiopathic autoinflammatory bone disease that mostly affects children and adolescents. It is a diagnosis of exclusions since no clinical signs and symptoms are pathognomonic. Radiological tests are often essential, but bone biopsy may be needed in unclear cases.

Case presentation

A 9-year-old Caucasian girl with a history of bone pain. The data from the history and results of laboratory tests suggested osteomyelitis, but no adequate response to the treatment was observed. A number of imaging tests did not confirm the diagnosis, therefore a bone biopsy was necessary.

Conclusions

Differential diagnosis of CRMO is challenging and it is based on exclusions. Since it might be misdiagnosed or mistreated, bone biopsy should be considered in patients reporting bone pain who are unresponsive to treatment.

Idiopathic CRMO and MEFV Gene Variant Alleles: Is There Any Relationship?

Background and Objective

CRMO is an inflammatory disease of bone that occurs more often in children. The clinical manifestations are intermittent fever, pain, and bone lesions, especially in long bones. Although there is an idiopathic type of disease, it is usually associated with some autoimmune disorders. This study evaluates MEFV gene mutations as background pathology of idiopathic CRMO.

Methods

Blood samples of patients, who diagnosed as childhood idiopathic CRMO by imaging and pathologic study from June 2011 until September 2018, have been screened for the 12 common pathogenic variants of MEFV gene mutations.

Result

Nine patients enrolled in this study, and eight of them were male. The most common involvement locations were tibia and femur, and the least ones were zygoma, calcaneus, and radius. The mean duration of the involvement was 1.3 years. Six patients had only 1 involved location, 2 patients showed two sites of involvement, and one patient had three affected areas. There were two positive MEFV gene mutations (22%), as E148Q/wt and K695R/wt both in the heterozygote form. There was no meaningful relationship between MEFV gene mutations and the age of onset, gender, and location of involvement. Patients with positive mutation had more involved sites and long duration of involvement significantly.

Conclusion

There is no significant immunopathogenic relationship between the common MEFV gene variant alleles and CRMO disease.

Biologic treatment for chronic recurrent multifocal osteomyelitis: report of four cases and review of the literature

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare non-infectious inflammatory disorder with unpredictable clinical course, characterized by acute exacerbations and spontaneous remissions. There are no randomized-controlled trials about treatment options. Non-steroidal anti-inflammatory drugs (NSAID) are the first-line treatment option; glucocorticoids seem to be effective; positive outcomes have been obtained with bisphosphonates. In the last few years successful use of biologic agents like anti-TNF agents has been reported. We report the cases of 3 children suffering from CRMO who were treated with NSAID, steroid, bisphosphonates and eventually received etanercept and 1 case without vertebral involvement treated with etanercept after NSAID and steroid; all cases showed clinical improvement. The mean ages at symptoms onset and diagnosis were 8 and 10 years and 10 months, respectively. Two patients presented with back pain and three had vertebral lesions. Mean interval from diagnosis to the onset of anti-TNF treatment was 14 months. According to our small experience, we suggest considering therapy with etanercept for the treatment of severe cases with persistently active disease despite multiple treatments.

Chronic Recurrent Multifocal Osteomyelitis in a 9-year-old Boy

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare aseptic, auto-inflammatory bone disorder. CRMO presents with bone pain with or without fever. The diagnosis of CRMO is a diagnosis of exclusion and should be included in the differential diagnosis of chronic inflammatory bone lesions in children. Cultures of the bone are typically sterile, antibiotic therapy does not result in clinical improvement whereas anti-inflammatory drugs improve the condition. Furthermore, biopsy should be considered in chronic and relapsing bone pain and swelling unresponsive to treatment. Herein, we present a nine-year-old boy complaining of recurrent pain in his upper and lower extremities. On examination he had mild fever and cervical lymphadenopathy. He also had experienced bone pain and weight loss in the recent month. Based on biopsy and bone scan he was finally diagnosed with CRMO. Naproxen and Pamidronate was prescribed and he was getting better and returned to normal life and activity without need to corticosteroids.