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

Therapeutic approaches for SAPHO syndrome from the perspective of pathogenesis: a review of the literature

Synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome is a rare autoinflammatory disease characterized by cutaneous manifestations and osteoarticular damage. The pathogenesis of SAPHO syndrome has not yet been elucidated, but studies have shown that the abnormal bone metabolism of patients with SAPHO syndrome is most likely due to localized infections that induce immune disorders in the body. Although no standardized treatment protocols exist, based on existing case studies and data from open studies, we propose that the treatment of SAPHO syndrome can be categorized into three areas according to the symptomatic manifestations of the disease: (1) control of focal infections using antibiotics and tonsillectomy; (2) administration of DMARDs to manage disease progression; and (3) bone remodeling therapy with bisphosphonates to address abnormal bone metabolism. Furthermore, a comprehensive treatment approach tailored to the clinical manifestations of the patient can effectively alleviate symptoms and enhance quality of life.

Geriatric chronic recurrent multifocal osteomyelitis (CRMO) mimicking multifocal multiple myeloma: a first in an octogenarian

Chronic recurrent multifocal osteomyelitis (CRMO), an autoinflammatory bone disorder characterized by non-bacterial osteomyelitis causing recurrent multifocal bone lesions, is a well-known, yet uncommon pediatric condition that rarely affects adults; to date, it has never been diagnosed over the age of 75. The following report will discuss the first octogenarian diagnosed with CRMO and therefore represents an exceptionally rare presentation of a rare disease. An 83-year-old woman presented with progressive right shoulder, forearm, and hip pain, with associated weight loss and global weakness, requiring a wheelchair for mobility. Imaging revealed a pathologic right ulna fracture in addition to lytic lesions of the right proximal humerus and proximal femur. The clinical picture was thus that of a patient with probable multiple myeloma versus metastatic disease. After an extensive workup, however, the lesions were not malignant; histologic findings were instead suggestive of chronic osteomyelitis with negative cultures. Given the multifocal nature of this condition, combined with a lack of clinical symptoms of infection, a diagnosis of CRMO was rendered. The patient underwent intramedullary nailing of the right femur and splinting of the ulna, with a subsequent remarkable recovery to painless ambulation, complete union of the right ulna fracture, and resolution of the lytic lesions without receiving any targeted medical treatment. This case highlights the importance of maintaining CRMO on the differential for multifocal skeletal lesions, regardless of age. Performing a thorough workup with necessary imaging, biopsy, and culture are critical to establishing this diagnosis, which can only made as a diagnosis of exclusion.

An improved understanding of pediatric chronic nonbacterial osteomyelitis pathophysiology informs current and future treatment

Chronic nonbacterial osteomyelitis (CNO) is an autoinflammatory bone disease that primarily affects children and young people. It can cause significant pain, reduced function, bone swelling, and even (vertebral body) fractures. Because of a limited understanding of its pathophysiology, the treatment of CNO remains empiric and is based on relatively small case series, expert opinion, and personal experience. Several studies have linked pathological NOD-kike receptor (NLR) family pyrin domain containing 3 (NLRP3) inflammasome activation and the resulting imbalance between pro- and anti-inflammatory cytokine expression with CNO. This agrees with elevated pro-inflammatory (mostly) monocyte-derived protein signatures in the blood of CNO patients that may be used as future diagnostic and/or prognostic biomarkers. Recently, rare variants in the P2RX7 gene, encoding for an ATP-dependent transmembrane channel, were linked with increased NLRP3 inflammasome assembly and prolonged monocyte/macrophage survival in CNO. Although the exact molecular mechanisms remain unclear, this will inform future target-directed and individualized treatment. This manuscript reviews most recent developments and their impact on diagnostic and therapeutic strategies in CNO.

Current and future advances in practice: SAPHO syndrome and chronic non-bacterial osteitis (CNO)

Synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome is a rare, underdiagnosed disease with a wide clinical spectrum. Sterile bone inflammation, predominantly of the anterior chest, and skin manifestations (palmoplantar pustulosis, psoriasis vulgaris and acne) are the key features of SAPHO, which shares certain similarities with SpA. SAPHO is closely related to paediatric chronic non-bacterial osteitis (CNO), a spectrum of autoinflammatory bone diseases. The aetiology of SAPHO is considered multifactorial based on a complex interplay of genetic, immune and infectious factors. Despite the increasing awareness of SAPHO/CNO, diagnostic delay is common, as validated classification and diagnostic criteria are lacking. Treatment of SAPHO represents a challenge and includes anti-inflammatory drugs, antibiotics, bisphosphonates, synthetic conventional DMARDs and off-label use of anti-cytokine biologics and Janus kinase inhibitors. This review summarizes the current diagnostic and practical treatment approach to SAPHO/CNO and highlights the ongoing research endeavours concerning the definition and validation of diagnostic criteria, core domains and treatment.

Systemic juvenile idiopathic arthritis with chronic recurrent multifocal osteomyelitis in an adolescent: A case report

Chronic recurrent multifocal osteomyelitis is a rare auto-inflammatory disease in children, with only a few reports of its association with other inflammatory diseases, such as systemic juvenile idiopathic arthritis. A 15-year-old boy was admitted due to fever, skin rash, arthritis, and high inflammatory factors and was finally diagnosed with systemic juvenile idiopathic arthritis. After 6 months of recovery from the disease, the patient was referred due to local pain and swelling in the arms and left thigh. In radiography, bone lesions were seen in the shoulders, left humerus, and left femoral diaphysis. A whole-body bone scan showed increased absorption in these areas, which suggested a tumor or osteomyelitis. A biopsy of the bone lesion of the left humerus confirmed sterile osteomyelitis. Although the co-incidence of chronic recurrent multifocal osteomyelitis with systemic juvenile idiopathic arthritis is rare, it should be considered in differential diagnosis.

A clinico-radiological review of chronic non-bacterial osteomyelitis in paediatrics, adolescents, and adults: demystifying a forgotten differential

Chronic non-bacterial osteomyelitis (CNO), also known as non-bacterial osteitis, is a chronic autoinflammatory disease of unknown aetiology that primarily occurs in the paediatric population, although rare cases of adult-onset disease also exist. CNO has non-specific clinical and radiological presentations, and the affected population often present with bone pain of insidious onset secondary to sterile bony inflammation that can be associated with swelling, focal tenderness, and warmth at the affected sites. The pattern of bony involvement appears to be dependent on the age of onset, with adults frequently having axial skeletal lesions and children and adolescents often being affected in the appendicular skeletal sites. CNO is a diagnosis of exclusion, and imaging is heavily relied on to identify and characterise the bony lesions in addition to exclude diseases that can mimic CNO. Magnetic resonance imaging is often the reference standard with biochemical and histopathological findings being complementary. Although combining imaging methods can be used to facilitate the diagnosis, a single technique could be adequate depending on the clinical picture. Given the relatively rare incidence of CNO, limited awareness of the disease among care providers, and its similarity in clinical and radiological presentation to various bony diseases, there are often long delays in diagnosis, with adults being unfavourably affected compared to paediatrics and adolescents. This review of CNO will describe the condition, overview its clinical presentation, highlight the radiological features, and emphasise clinical pearls that can aid in diagnosis and ruling out the mimics.

Adult-onset chronic recurrent multifocal osteomyelitis: a case report

Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory bone disease predominantly affecting the metaphyses of long bones and is usually seen in children. Although CRMO is generally a pediatric disease, it may also occur in adults. This may result in a delay in the diagnosis of adult-onset CRMO. This report presents an adult-onset female patient who presented with left leg pain followed by swelling in the right knee. The patient was initially started on colchicine treatment, but, due to unresponsiveness in the follow-up the patient, the treatment was switched to a combination of methotrexate and prednisolone. A satisfactory clinical recovery was achieved with these drugs. CRMO could be considered in the differential diagnosis of patients presenting with bone pain and joint complaints. Considering that the disease progresses with clinical flare-ups and remission periods, it should be kept in mind that patients should be followed closely and treatment can be changed.

Severe chronic non-bacterial osteomyelitis in combination with total MPO deficiency and responsiveness to TNFα inhibition

We describe a female patient suffering from severe chronic non-bacterial osteomyelitis (CNO) with systemic inflammation and advanced malnutrition and complete deficiency of myeloperoxidase (MPO). CNO is a rare autoinflammatory bone disorder associated with dysregulation of the innate immune system. MPO deficiency is a genetic disorder with partial or complete absence of the phagocyte peroxidase MPO. MPO deficiency has no established clinical phenotype but reports indicate increased susceptibility to infection and chronic inflammation. The patient's symptoms began at 10 years of age with pain in the thighs, systemic inflammation and malnutrition. She was diagnosed with CNO at 14 years of age. Treatment with nonsteroidal anti-inflammatory drugs, corticosteroids, bisphosphonates or IL1-receptor antagonists (anakinra) did not relieve the symptoms. However, the patient responded instantly and recovered from her clinical symptoms when treated with TNFα blockade (adalimumab). Three years after treatment initiation adalimumab was withdrawn, resulting in rapid symptom recurrence. When reintroducing adalimumab, the patient promptly responded and went into remission. In addition to clinical and laboratory profiles, neutrophil functions (reactive oxygen species, ROS; neutrophil extracellular traps, NETs; degranulation; apoptosis; elastase activity) were investigated both in a highly inflammatory state (without treatment) and in remission (on treatment). At diagnosis, neither IL1β, IL6, nor TNFα was significantly elevated in serum, but since TNFα blockade terminated the inflammatory symptoms, the disease was likely TNFα-driven. All neutrophil parameters were normal both during treatment and treatment withdrawal, except for MPO-dependent intracellular ROS- and NET formation. The role of total MPO deficiency for disease etiology and severity is discussed.

New insights on multigenic autoinflammatory diseases

Autoinflammatory diseases are disorders of the innate immune system, which can be either monogenic due to a specific genetic mutation or complex multigenic due to the involvement of multiple genes. The aim of this review is to explore and summarize the recent advances in pathogenesis, diagnosis, and management of genetically complex autoinflammatory diseases, such as Schnitzler's syndrome; adult-onset Still's disease; synovitis, acne, pustulosis, hyperostosis, osteitis syndrome/chronic recurrent multifocal osteomyelitis/chronic non-bacterial osteomyelitis; Adamantiades-Behçet's disease; Yao syndrome; and periodic fever with aphthous stomatitis, pharyngitis, and adenitis syndrome. The PubMed database was screened for relevant articles using free text words and specific search strings. The search was limited to English-language articles, reporting the results of studies in humans, published through March 2021. Evidence from literature suggest that these rare multigenic autoinflammatory diseases can present with different clinical features and the diagnosis of these diseases can be challenging due to a combination of nonspecific manifestations that can be seen in a variety of other conditions. Diagnostic delays and disease complications may occur due to low disease awareness and the lack of pathognomonic markers. The pathogeneses of these diseases are complex and in some cases precise pathogenesis is not clearly understood. Conventional treatments are commonly used for the management of these conditions, but biologics have shown promising results. Biologics targeting proinflammatory cytokines including IL-1, IL-6, TNF-α, IL-17A and IL-18 have been shown to ameliorate signs and symptoms of different multigenic autoinflammatory diseases.

Chronic nonbacterial osteomyelitis in children: a multicentre Belgian cohort of 30 children

BACKGROUND

To evaluate clinical characteristics, imaging findings, therapeutic approach and outcome of paediatric patients with Chronic Non-Bacterial Osteomyelitis (CNO).

METHODS

Retrospective review of 30 children diagnosed with CNO at two tertiary care centres in Belgium. Imaging data were evaluated by blinded paediatric radiologists.

RESULTS

Mean age at onset was 10.3 years and mean age at diagnosis was 11.7 years. Bone pain was the leading symptom (29/30 patients). Out of 180 symptomatic lesions, 131 were confirmed on MRI as hyperintense geographic lesions on STIR images at the metaphysis and epiphysis adjacent to growth plates of tubular bones. The most common sites of involvement were the lower limbs, spine, sternoclavicular joint and humerus. For nearly half of the patients (14/30) monotherapy with NSAIDs was sufficient to obtain remission. The remaining 16 patients received second-line therapy: bisphosphonates (n = 15/30), disease-modifying antirheumatic drugs (n = 7/30), etanercept (n = 4/30) and tocilizumab (n = 1/30). Remission was reached after a mean time of 37.6 months in 26/30 patients. The prognosis was worse for patients with spinal involvement, resulting in more long-term sequelae.

CONCLUSIONS

We present a multicentre paediatric cohort of 30 CNO patients. A typical pattern of bone involvement could be found on MRI. NSAIDs were administered as first-line treatment. Second-line strategies included bisphosphonates, corticosteroids, methotrexate, etanercept and tocilizumab.

TRIAL REGISTRATION

Retrospectively registered. Registratienummer EC KUL: MP018023.

TNF-inhibitors or bisphosphonates in chronic nonbacterial osteomyelitis? - Results of an international retrospective multicenter study

Chronic nonbacterial osteomyelitis (CNO) can cause significant morbidity, including bone pain and damage. In the absence of clinical trials, treatments include non-steroidal anti-inflammatory drugs, corticosteroids, TNF-inhibitors (TNFi) and/or bisphosphonates. In a retrospective chart review in the United Kingdom and Germany, we investigated response to TNFi and/or pamidronate. Ninety-one patients were included, receiving pamidronate (n = 47), TNFi (n = 22) or both sequentially (n = 22). Patients with fatigue [p = 0.003] and/or arthritis [p = 0.002] were more frequently treated with TNFi than pamidronate. Both therapies were associated with clinical remission at 6 months, and reduction of bone lesions on MRI at 12 months. While not reaching statistical significance, pamidronate resulted in faster resolution of MRI lesions. Fewer flares were observed with TNFi. Failure to respond to pamidronate was associated with female sex [p = 0.027], more lesions on MRI [p = 0.01] and higher CRP levels [p = 0.03]. Randomized clinical trials are needed to confirm observations and generate evidence.

New Insights in the Treatment of SAPHO Syndrome and Medication Recommendations

Synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome is a rare autoinflammatory disease characterized by dermatological disorders and osteoarticular inflammatory lesions. This article reviews the application of biologics and other treatments based on the therapeutic target and the size of molecules in SAPHO syndrome. We found that drugs, especially biologics, have different effects on bone, joint, and skin damage. This may relate to the different inflammatory pathways involved in the osteoarticular and cutaneous symptoms in SAPHO patients. In this study, we provide stratified medication recommendations for SAPHO syndrome. Patients with osteoarticular symptoms can consider tumor necrosis factor blockers, JAK inhibitor, interleukin (IL)-1 inhibitor, and IL-17 inhibitor. Patients with cutaneous symptoms should consider IL-17 and JAK inhibitors. Apremilast, Tripterygium wilfordii Hook F, and bisphosphonates are other effective treatments.

Clinical and Genetic Features of Chinese Adult Patients With Chronic Non-Bacterial Osteomyelitis: A Single Center Report

Objectives

Chronic non-bacterial osteomyelitis (CNO) is a rare polygenic autoinflammatory bone disease. We aimed to characterize the clinical manifestations and gene variants of Chinese adult patients with CNO.

Methods

By reviewing data of all CNO patients being diagnosed and followed up at the Center for Adult Autoinflammation Diseases, Department of Rheumatology, Peking Union Medical College Hospital, clinical and genetic features of these patients were evaluated and concluded.

Results

The median age of disease onset was 19 (6-64) years old, and adult-onset was observed in 6 (60%) patients. The mean time of diagnosis delay was 92 ± 78 months. The common symptoms were bone pain (10, 100%), fever (9, 90%), and arthritis (6, 60%). In total, there were 54 skeletal lesions, and each patient had no less than 2 lesions. The most frequently affected sites included lower limbs (20.5%), mandible, vertebrae and pelvis (17.5%, separately). Variants of 4 genes were detected in our study including COL1A1, PSTPIP1, LRP5 and CLCN7. In seven patients who were treated with combination therapy containing tumor necrosis factor (TNF) α inhibitors, five (55.6%) had a complete response and 2 (44.4%) had a partial response.

Conclusion

This is the first and largest case series of CNO in the Chinese adult patients. Four novel genetic mutations potentially associated with CNO were identified. Notably, CNO should be considered in the differential diagnosis of adult patients with long disease course and recurrent multifocal osteomyelitis of unknown cause, and these patients might benefit from combination therapy containing TNFα inhibitors.

Pharmacological Management of Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis Syndrome Syndrome: A Proposal of a Treatment Algorithm

ABSTRACT

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare chronic disease with marked clinical and radiological heterogeneity. It is characterized by a combination of dermatological and osteoarticular manifestations. The treatment of SAPHO syndrome is not yet codified. It includes several therapeutic options such as anti-inflammatory drugs, bisphosphonates, antibiotics, conventional disease-modifying antirheumatic drugs, and biological treatment.This article aims to provide an updated review of the different pharmacological options for SAPHO syndrome. We also propose a therapeutic algorithm for the management of this disease.

Cranial aseptic osteomyelitis associated with pyoderma gangrenosum

Neutrophilic dermatoses include a heterogeneous group of entities. Uncommonly, they can accumulate aseptic neutrophilic abscesses in other tissues in addition to the skin. A 34-year-old female complained of a headache which was unresponsive to usual drugs. A TAC revealed an osteolytic lesion in the right parietal bone. The biopsy showed osteomyelitis. One year later, pyoderma gangrenosum appeared in the anterior aspect of both legs. The headache and the cutaneous lesions disappeared after treatment with oral prednisone. The bone involvement in the background of neutrophilic dermatoses is exceptional. Usually, it involves children in the context of chronic recurrent multiple osteomyelitis (CRMO). Only two cases have been described in adults. One of them was a 26-year-old woman who had had CRMO since childhood, and the other one in contiguity with the cutaneous lesions of pyoderma gangrenosum.

Cranial aseptic osteomyelitis associated with pyoderma gangrenosum

Neutrophilic dermatoses include a heterogeneous group of entities. Uncommonly, they can accumulate aseptic neutrophilic abscesses in other tissues in addition to the skin. A 34-year-old female complained of a headache which was unresponsive to usual drugs. A TAC revealed an osteolytic lesion in the right parietal bone. The biopsy showed osteomyelitis. One year later, pyoderma gangrenosum appeared in the anterior aspect of both legs. The headache and the cutaneous lesions disappeared after treatment with oral prednisone. The bone involvement in the background of neutrophilic dermatoses is exceptional. Usually, it involves children in the context of chronic recurrent multiple osteomyelitis (CRMO). Only two cases have been described in adults. One of them was a 26-year-old woman who had had CRMO since childhood, and the other one in contiguity with the cutaneous lesions of pyoderma gangrenosum.

[Chronic multifocal osteomyelitis: A case report and literature review]

A case of chronic multifocal osteomyelitis was described in terms of its clinical manifestations, serological and imaging examinations, diagnostic criteria, treatment options, and follow-up evaluation after discharge. The pathogenesis, diagnosis, differential diagnosis and treatment of chronic multifocal osteomyelitis were reviewed, and the characteristics of autoinflammatory osteopathy were reviewed. The patient with onset from youth had developed severe skin lesions, progressive arthralgia and rachialgia. The clinical manifestation and the auxiliary examination of the patient accorded with the diagnosis of chronic multifocal osteomyelitis. After poor anti-inflammatory and analgesic effects, the switch to tumor necrosis factor alpha (TNF-α) inhibitor resulted in pain relief, normalization of inflammation indexes, and significant improvement in rash and imaging examination. Chronic recurrent multifocal osteomyelitis was a kind of autoinflammatory bone disease of multiple genes in disease with low incidence, unknown mechanism and unified diagnostic criteria. It was also known as chronic nonbacterial osteomyelitis, which was a rare, noninfectious inflammatory disorder that caused multifocallytic bone lesions characterized by periodic exacerbations and remissions. The exact pathophysiology or mechanism of the sterile bone inflammation was poorly understood, although chronic nonbacterial osteomyelitis was probably an osteoclast-mediated disease. In addition, an imbalance between pro- and anti-inflammatory cytokines was suspected to play a role. The available data so far pointed to the interplay among genetics, environmental, and immunologic factors as the causes of chronic nonbacterial osteomyelitis. Infectious etiology did not seem to play a crucial role in the pathogenesis of chronic nonbacterial osteomyelitis. It was often confused with metabolic bone disease, infection, tumor and other diseases. Its clinical manifestations were bone pain, fever, rash, fracture and so on. Laboratory examination showed significant increase in inflammatory markers. Radiographic examination revealed osteolytic or sclerosing changes. Magnetic resonance imaging was very useful for identifying bone lesions and tissue edema and was more accurate than bone emission computed tomography (ECT). Most of the patients begin to use non-steroidal anti-inflammatory drugs (NSAIDs) for treatment, but they are prone to relapse and new lesions appear. Other treatment options can be selected, including glucocorticoids, TNF-α inhibitors, bisphosphonates, methotrexate and other disease-modifying anti-rheumatic drugs (DMARDs). Early diagnosis and treatment can prevent and reduce complications and improve prognosis.

Synovitis, acne, pustulosis, hyperostosis, and osteitis syndrome: review and update

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a spectrum of heterogeneous diseases characterized by osteoarticular and dermatological manifestations. Osteitis and hyperostosis are core clinical manifestations in SAPHO syndrome, typically affecting multiple areas and possibly progressing to irreversible osteoarticular damage. Most patients with SAPHO have cutaneous involvement, mainly manifested as palmoplantar pustulosis and severe acne. Systemic manifestations are uncommon but occasionally reported. Epidemiological studies suggest the annual prevalence of SAPHO syndrome varies from 0.00144 in 100,000 in Japanese individuals to fewer than 1 in 10,000 in White individuals. The precise etiopathogenesis of SAPHO remains unclear, but it is generally considered an autoinflammatory syndrome that may be related to various etiologies, such as immune dysfunction, infection and genetic predisposition. Owing to the relapsing-remitting disease course, the goal of management is to improve clinical symptoms and prevent disease progression. Various treatments, including nonsteroidal anti-inflammatory drugs, conventional disease-modifying antirheumatic drugs, bisphosphonates, biologics, and antibiotics, are promising options for alleviating the disease.

SAPHO: has the time come for tailored therapy?

SAPHO (synovitis, acne, pustulosis, hyperostosis and osteitis) syndrome is a heterogeneous condition combining osteoarticular and cutaneous manifestations. Conventional treatments are mostly ineffective. We hereby report two patients, the first with an aggressive form of disease and the second with an incomplete response to two different anti-TNF-α agents. Both were successfully treated with tocilizumab and ustekinumab, respectively, over a long period of time. A narrative review of a biological therapy in SAPHO syndrome yielded very little information on the specific use of these agents. We highlight the advantages of personalising therapy and describe emerging promising treatments for this disease.

Dramatic Response of Familial Majeed Syndrome to Interleukin-1 Antagonist Therapy: Case report

Majeed syndrome (MS) is a rare, autosomal recessive, autoinflammatory disease characterized by recurrent multifocal osteomyelitis, congenital dyserythropoietic anemia, and inflammatory dermatome. In this article, we report the cases of two siblings with MS. Genetic studies of both siblings were obtained and revealed mutations in LPIN2 gene by means of a homozygous single-base pair change in the donor splice site of exon 17 (c.2327+1G>C). Both patients underwent different modalities of treatment for MS which involved immune-suppressive and biologic therapies. We observed a significant clinical response to biologic anti-interleukin-1 (IL-1) therapy in our patients. This impressive clinical response indicates the pivotal role of IL-1 in MS pathogenesis. There are limited data on the use of anti-IL-1 therapy in treating MS due to the rarity of the condition. Anti-IL-1 therapy should be considered as a promising treatment for this disease.

Failure of tocilizumab in treating two patients with refractory SAPHO syndrome: a case report

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare autoinflammatory disease with no standard treatment. Interleukin (IL)-6 inhibitors represent a novel therapeutic option for rheumatoid arthritis and some autoinflammatory diseases. However, the clinical utility of IL-6 inhibitors in treating SAPHO syndrome has been poorly investigated. In the present report, we describe two patients with SAPHO syndrome that was unresponsive to conventional treatment. Tocilizumab, an anti-IL-6 receptor monoclonal antibody, was putatively administered according to positive IL-6 immunohistochemical staining in biopsied bone tissues. However, the disease continued to progress, and new-onset or worsening skin lesions were noted with transient neutropenia. These cases demonstrate that tocilizumab may not be an ideal option for treating SAPHO syndrome.

Comparison of different treatment approaches of pediatric chronic non-bacterial osteomyelitis

Chronic non-bacterial osteomyelitis (CNO) is a chronic inflammatory bone disease which usually manifests in children and adolescents. There are a few data about pathogenesis and treatment. The aim of the study to compare the efficacy of different treatment approaches in pediatric CNO cohort patient. Fifty two children (25 boys and 27 girls) with CNO with average age at the onset of the disease 8.4 years (5.4; 11.0), number of foci - 3.0 (2.0; 6.0, incl. multifocal cases in 80.8%). Non-steroid anti-inflammatory drugs (NSAID) was the first-line treatment for non-vertebral cases, as well as pamidronate (PAM) for vertebral involvement. Second-line treatment includes sulfasalazine (SSZ), methotrexate (MTX), PAM and tumor necrosis factor-α inhibitors (TNFα-inh). We evaluated the dynamics of pain, patient's and physician's (MDVAS) assessment with visual-analog scale (VAS) and ability to each medication to achieve remission of CNO activity. According to the NSAID, MTX, SSZ, PAM and TNFα-inh groups the following data were registered: patient's VAS: - 14.2% (p = 0.05), - 50.0% (p = 0.04), - 23.1 (p = 0.89), - 83.3% (p = 0.0001), - 73.6% (p = 0.0007); painVAS: - 21.9% (p = 0.01), - 18.6% (p = 0.13), + 36.4 (p = 0.89), - 79.7% (p = 0.00016), - 74.1%, (p = 0.0015); MDVAS: - 13.8% (p = 0.13); - 56.4% (p = 0.09), + 30.8% (p = 0.89), - 74.7%, (p = 0.0001), - 82.1 (p = 0.0015) respectively. The ability of each treatment strategy to achieve the CNO remission was 52.6%, 44.4%, 57,1%, 88.8% and 73.3%, respectively (log-rank test, p = 0.001). The efficacy of treatment approaches for CNO depended on the severity of the disease. NSAID, methotrexate, and sulfasalazine were effective in forms without spine involvement, but pamidronate and TNF-a inhibitors were useful in vertebral forms of CNO. Pamidronate and TNF-a inhibitors more extensively suppressed CNO activity. The randomized controlled trials for assessment of the efficacy and safety of these medications is mandatory to confirm these results.