Two phenotypes of chronic recurrent multifocal osteomyelitis with different patterns of bone involvement.

INTRODUCTION: Chronic Recurrent Multifocal Osteomyelitis (CRMO) is an autoinflammatory bone disorder with predominantly paediatric onset. Children present with multifocal osteolytic lesions accompanied by bone pain and soft tissue swelling. Patients often exhibit extraosseous co-morbidities such as psoriasis, inflammatory bowel disease, and arthritis. OBJECTIVES: Comparison of children with two different phenotypes of CRMO defined by presence or absence of extraosseous co-morbidities. METHODS: Children diagnosed with CRMO at the Motol University Hospital between 2010 and 2020 were retrospectively reviewed, and according to the absence or presence of extraosseous manifestations divided into two cohorts - bone limited CRMO and complex CRMO. The two groups were compared in terms of demographic data, age at disease onset, number and site of bone lesions, laboratory biomarker values, and need of escalation to a second-line therapy. RESULTS: Thirty-seven children (30 female, 7 male) with confirmed CRMO were included in the analysis. The mean age at disease onset was 10 years. All but 3 patients presented with multifocal disease. Twenty-three children (62%) had at least one extraosseous manifestation (13 sacroiliitis, 8 inflammatory bowel disease, 6 skin disease [acne, pustulosis, or psoriasis], 7 arthritis). Complex CRMO was associated with a significantly higher ESR rate (p = 0.0064) and CRP level (p = 0.018). The groups did not differ in number of foci or in age at disease onset. Bone lesion distribution differed between the two groups with significantly more frequent involvement of clavicle (p = 0.011) and pelvis (p = 0.038) in patients with complex CRMO. Children with complex CRMO more often needed escalation of therapy to DMARDs and biologic agents. CONCLUSION: Our data suggest that CRMO affecting solely the skeleton has milder course compared to complex CRMO with extraskeletal features. Further studies are needed to explore the clinical as well as the patient reported outcomes and promote individually tailored therapeutic strategies in both CRMO phenotypes.

[Primary malignant bone tumors in children possibilities of limb-saving surgery using allografts]. / Primární maligní nádory kostí u detí moznosti záchovné chirurgie s vyuzitím alostepu.

Therapy of primary malignant bone tumors is always multimodal and requires close cooperation of oncologist, orthopedic surgeon, radiologist and others. In our article, we provide a brief overview of the most common malignant bone tumors in pediatric patients and summarize the commonly used therapeutic procedures. Despite advances in cancer treatment radical surgical resection of the tumor is still necessary. If possible, it should be complete removal of the affected structures, made in terms of the so-called limb-saving (limb-sparing) surgery that preserves the shape and function of the affected limb to the fullest extent possible. In addition the resection must be done at the same time with substitution of the removed bone. Bone grafts, both autografts and allografts, are used in majority of solutions. We also discuss the comparison of different approaches of limb-saving surgery compared to ablative procedures.