The SAPHO syndrome: a clinical and imaging study

Long-term clinical course of two rare cases of synovitis-acne-pustulosis-hyperostosis-osteomyelitis syndrome involving only unilateral femur

Synovitis-acne-pustulosis-hyperostosis-osteomyelitis (SAPHO) syndrome is characterised by aseptic osteitis and is often complicated by pustular dermatitis, such as palmoplantar pustulosis or acne. Although bone lesions are most found in the anterior thoracic region or spine, femoral lesions are not well documented in the literature. There is no established treatment for this condition, and few reports have described its long-term course. Here, we describe two cases of SAPHO syndrome involving the femur and discuss their long-term follow-up. A 40-year-old man (Case 1) presented with right thigh pain. Fifteen years after the initial diagnosis, the pain could be controlled with minomycin, salazosulfapyridine, and methotrexate. X-rays of the femur showed gradual cortical thickening. Although there were waves of pain, it gradually improved with the adjustment of drugs 25 years following the initial diagnosis. A 35-year-old man (Case 2) with right thigh pain was prescribed salazosulfapyridine and methotrexate; however, these were ineffective. Alendronate and guselkumab also proved ineffective. Ultimately, infliximab was started 9 years following disease onset, and pain became manageable. X-rays of the femur showed cortical thickening. SAPHO syndrome can be managed with drug therapies, such as nonsteroidal anti-inflammatory drugs, methotrexate, and conventional synthetic disease-modifying antirheumatic drugs; however, there are occasional treatment-resistant cases.

The challenging diagnosis of synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) syndrome: A rare case report

Considered rare, the synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) syndrome is a distinct clinical entity, associating skin manifestations and osteoarticular symptoms. Anterior chest wall pain centered at sternoclavicular and sternocostal joints is an important and characteristic clinical finding that can lead to its diagnosis. Radiologists and clinicians must be aware of synovitis-acne-pustulosis-hyperostosis-osteitis syndrome as it can mimic some of the more common disease entities such as Paget's disease. We report the case of a 63-year-old male patient, with no significant medical history, who presented to the dermatology department, with severe palmar and plantar pustulosis associated with polyarthralgia. Computerized tomography scan showed sternoclavicular hyperostosis, in favor of SAPHO syndrome, with regression of clinical symptoms after non-steroidal anti-inflammatory drug treatment.

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.

Dysphagia Secondary to Myotonic Dystrophy Unveiled in a Case of Destructive Spondylitis With Synovitis, Acne, Pustulosis, Hyperostosis, Osteitis (SAPHO) Syndrome Presenting As Torticollis

To report an instructive case involving destructive spondylitis and synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) syndrome, presenting with torticollis and postoperative dysphagia without hoarseness, attributed to hidden myotonic dystrophy (DM). A 51-year-old male patient with a cervical deformity, who was previously managed conservatively for a metastatic tumor, underwent reconstruction surgery and subsequently experienced postoperative dysphagia. The presence of destructive spondylitis with torticollis, warranting prompt assessment to prevent paralysis, adds complexity to the delayed identification of DM. Given the rarity of DM, peculiar neurological symptoms and other systemic comorbidities did not lead to a preoperative diagnosis without prior knowledge. The patient's dysphagia induced respiratory arrest and required reintubation. Challenges in extubation and ventilator weaning arose due to hypercapnia. Superimposed COVID-19 infection elongated the duration of intubation. Extubation failed due to aspiration pneumonia and required a tracheotomy. Despite laryngeal elevation and preservation of the relaxation of the oesophageal entrance, the sensation and movement of the tracheopharynx were disturbed. The patient exhibited an oropharyngeal propulsive disorder, predominantly indicative of motor neuron disease. The patient's mother stated that his brother had been hospitalized for a long time after abdominal surgery. Finally, the patient was diagnosed with DM, which is known to cause post-anesthetic dysphagia. Recognizing the existence of severe destructive cervical spondylitis associated with SAPHO is crucial. Although DM is not very common, it is not classified as extremely rare. Therefore, surgeons should be mindful of the potential risks associated with general anesthesia in patients with DM. The complexity of preoperative conditions may hinder an accurate diagnosis. Recognizing and establishing preoperative expectations can assist surgeons in preventing complications, even if complex spinal surgery is required for patients with DM.

The clinical characteristics and prognosis of patients with SAPHO syndrome--a real-world cohort study

OBJECTIVES

We aimed to analyze the clinical characteristics and outcomes of patients with synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome.

METHODS

The clinical records of 64 patients with SAPHO syndrome were collected, and the treatment and outcomes of 27 patients were followed up. The patients were divided into three groups according to the site of bone lesions: only anterior chest wall (ACW) involvement, only spinal involvement, and bone lesion involvement at both sites. The clinical characteristics and outcomes were compared. The clinical characteristics of the patients with and without peripheral joint involvement were compared.

RESULTS

Among all patients, 31.25% (20/64) had only ACW involvement, 15.63% (10/64) had only spinal involvement, and 53.12% (34/64) had both ACW and spinal involvement. Peripheral joint involvement was observed in 25.00% (16/64) of the patients. Patients with only spinal involvement were older than those with only ACW involvement (p = 0.006). Patients with both ACW and spinal involvement were older than those with only ACW involvement (p = 0.002) and had a longer diagnosis delay (p = 0.015). Patients with peripheral joint involvement were younger than those without peripheral joint involvement (p = 0.028). During follow-up, 88.89% (24/27) of patients had good outcomes. Twenty-two patients were treated with non-steroidal anti-inflammatory drugs + Iguratimod (IGU), and the outcomes of 90.91% (20/22) improved.

CONCLUSIONS

A relationship may exist between the sites of bone lesions and clinical characteristics of patients with SAPHO syndrome. The clinical outcomes of these patients may be good, and IGU may be effective in treating SAPHO syndrome. Key Points • This study is the first long-term follow-up on the effectiveness of iguratimod in treating patients with SAPHO. • This study revealed that patients with SAPHO and different bone lesion sites may present with different clinical characteristics.

Unusual cause of inflammatory backache: SAPHO syndrome

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) is a rare chronic inflammatory disease that develops in adults. We present a case of SAPHO syndrome in a 37-year-old male presenting with gradually worsening back and neck pain for a 7-year period. The episodes were preceded by a history of pustular skin eruptions, which first appeared on the upper trunk and then involved his face and were pustular and scarring. The purpose of presenting this case report from Iraq is to raise awareness about this rare condition, which is frequently misdiagnosed and under-recognized.

Prospective Comparison of the Imaging Value of 99m Tc-MDP Bone Scan and 68 Ga-FAPI-04 PET/CT in Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis Syndrome

PURPOSE

This study aimed to explore the imaging value of 68 Ga-FAPI-04 PET/CT in synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and compare it with that of 99m Tc-MDP bone scan.

METHODS

Nineteen participants with SAPHO syndrome underwent 68 Ga-FAPI-04 PET/CT and 99m Tc-MDP bone scan. Demographic data and clinical features were recorded, SAPHO imaging features were analyzed, and the osteoarticular lesion detection rate in both methods was calculated.

RESULTS

This prospective study recruited 4 men and 15 women aged 52.4 ± 8.6 years. The anterior chest wall was involved in all participants (100%). Palmoplantar pustulosis was the most common (36.8%) skin symptom. 99m Tc-MDP bone scan and 68 Ga-FAPI-04 PET/CT together detected 84 osteoarticular lesions, of which 91.7% (77/84) were detected by the former and 96.4% (81/84) by the latter. Furthermore, 68 Ga-FAPI-04 PET/CT detected 5 cases of knee and hip joint synovitis.

CONCLUSIONS

68 Ga-FAPI-04 PET/CT was more sensitive than 99m Tc-MDP bone scan when evaluating osteoarticular lesions in SAPHO syndrome and could also evaluate synovial lesions. 68 Ga-FAPI-04 PET/CT could be a good imaging method for SAPHO syndrome but requires further verification in a more extensive research cohort.

Clinical and therapeutic diversity in adult chronic nonbacterial osteomyelitis (CNO) of the sternocostoclavicular region: a meta-analysis

OBJECTIVES

Chronic nonbacterial osteomyelitis (CNO) is a rare inflammatory bone disease. The distinct CNO subtype that affects the anterior chest wall is descriptively named sternocostoclavicular hyperostosis (SCCH) and mainly occurs in adults. Literature on CNO/SCCH is scattered and lacks diagnostic and therapeutic consensus.

METHODS

Systematic review and meta-analysis aiming to characterize clinical presentation and therapeutic modalities applied in adult CNO/SCCH patients. Untransformed numerical data and double-arcsine transformed proportional data were pooled in a random effects model in R-4.0.5; proportions were reported with 95% CI.

RESULTS

Forty studies were included, containing data on 2030 and 642 patients for aim 1 and 2, respectively. A female predisposition (67%, 95% CI 60, 73) and major diagnostic delay (5 years 95% CI 3, 7) were noted. Clinical presentation included chest pain (89%, 95% CI 79, 96) and swelling (79%, 95% CI 62, 91). Patients suffered from pustulosis palmoplantaris (53%, 95% CI 37, 68), arthritis (24%, 95% CI 11, 39) and acne (8%, 95% CI 4, 13). Inflammatory markers were inconsistently elevated. Autoantibody and HLA-B27 prevalence was normal, and histopathology unspecific. Increased isotope uptake (99%, 95% CI 96, 100) was a consistent imaging finding. Among manifold treatments, pamidronate and biologicals yielded good response in 83%, 95% CI 60, 98 and 56%, 95% CI 26, 85, respectively.

CONCLUSION

CNO/SCCH literature proves heterogeneous regarding diagnostics and treatment. Timely diagnosis is challenging and mainly follows from increased isotope uptake on nuclear examination. Biopsies, autoantibodies and HLA status are non-contributory, and biochemical inflammation only variably detected. Based on reported data, bisphosphonates and biologicals seem reasonably effective, but due to limitations in design and heterogeneity between studies the precise magnitude of their effect is uncertain. Fundamentally, international consensus seems imperative to advance clinical care for CNO/SCCH.

Morphologic Alterations of the Sternoclavicular Joint following Ipsilateral Clavicle Fractures

RATIONALE

To our knowledge, no study has investigated concomitant injuries of the sternoclavicular joint (SCJ) in acute clavicle fractures. The purpose of this study was to determine the effect of an ipsilateral clavicle fracture on the SCJ in a systematic computer tomography (CT) morphologic evaluation.

METHODS

CT scans in the axial and coronal plane of 45 consecutive patients with clavicle fractures were retrospectively analyzed. The scans were assessed regarding anatomic congruence of bilateral SCJs-joint space width (JSW); the position of bilateral medial clavicles (PC); and the non-fusion of epiphyses, arthritis, calcifications, and intra-articular gas.

RESULTS

The mean SCJ JSW was significantly different in the coronal (cJSW; 8.70 mm ± 2.61 mm in affected vs. 7.63 mm ± 2.58 mm in non-affected side; p = 0.001) and axial plane (aJSW; 9.40 mm ± 2.76 mm in affected vs. 9.02 ± 2.99 in non-affected SCJs; p = 0.044). The position of the medial clavicle showed a significant difference in the coronal plane (cPC; 14.31 mm ± 3.66 mm in the affected vs. 13.49 ± 3.34 in the non-affected side; p = 0.011), indicating a superior shift.

CONCLUSION

Acute clavicle fractures may be associated with an enlargement of the ipsilateral SCJ space width and a superior shift of the proximal clavicle. Both morphologic alterations could indicate concomitant injuries of the SCJ as well as a potential increase in the risk of SCJ instability.

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.

Destructive spondylodiscitis associated with SAPHO syndrome: A case report and literature review

Background:

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare sterile inflammatory disease characterized by cutaneous and osteoarticular lesions. Associated spinal lesions chronically manifest slight or no neurological symptoms. Only rarely does destructive spondylodiscitis occur.

Case Description:

A 62-year-old female with palmoplantar pustulosis presented with a rapidly progressive quadriparesis. When the cervical MR showed destructive spondylodiscitis at the C5–C7 level, the patient underwent anterior debridement followed by posterior reconstruction/fixation. The histopathology showed a nonspecific inflammatory process with vertebral sclerosis consistent with the diagnosis of SAPHO; cultures were negative. Postoperatively, the patient’s symptoms improved and SAPHO did not recur.

Conclusion:

Destructive spondylodiscitis associated with SAPHO syndrome is uncommon. Early diagnosis and surgical treatment result in the best outcomes.

Pro and contra: is synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) a spondyloarthritis variant?

PURPOSE OF REVIEW

The purpose of this review is to present the up-to-date evidence on the epidemiology, pathogenesis, musculoskeletal manifestations, and imaging of the synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and to discuss its relationship with spondyloarthritis (SpA).

RECENT FINDINGS

SAPHO is a rare inflammatory disorder of bone, joints, and skin, with a worldwide distribution that predominantly affects the middle-age adults. The hallmark of the syndrome is a constellation of sterile inflammatory osteitis, hyperostosis, and synovitis involving the anterior chest wall, associated with acneiform and neutrophilic dermatoses, such as palmoplantar pustulosis and severe acne. The axial skeleton, sacroiliac, and peripheral joints can be involved in a similar fashion to SpA. The pathogenesis of the syndrome is multifactorial. The diagnosis is mainly based on the clinical and typical radiological features. The treatment approach is based on the off-label use of antibiotics, bisphosphonates, disease-modifying antirheumatic drugs, and anticytokine biologics.

SUMMARY

The SAPHO syndrome shares common features with SpA-related diseases, yet also shows some unique pathogenetic and clinical features. The nosology of SAPHO remains a subject of controversy, awaiting further research into the pathogenetic and clinical aspects of this syndrome. A better understanding of these aspects will improve the diagnostics and clinical care of patients with SAPHO.

SAPHO Syndrome Presenting With Atlo-Epistrophic Synovitis and Left Vocal Cord Paresis: A Challenging Diagnosis

SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) is a rare syndrome mainly characterized by cutaneous and osteoarticular manifestations. The most typical osteoarticular manifestations are localized to the anterior chest wall and include a usually noninfectious osteitis, hyperostosis, and synovitis of the sternoclavicular joints. However, clinical presentation of SAPHO syndrome can be quite heterogeneous. Several clinical and radiological features are shared with other well-defined pathological entities, and clinical signs and symptoms often occur at different timepoints. Mainly due to this complexity and its rarity, there are currently no validated diagnostic criteria for SAPHO syndrome. Inflammation of the soft tissues around the bones and possible nerve compression could contribute to dysphagia, hypophonia, or obstruction of the airways. Neurologic manifestations could therefore be part of this multiorgan involvement. Here, we present a case of SAPHO syndrome with atypical onset symptoms, characterized by left vocal cord paralysis, acute neck pain due to osteolytic atlantoepistrophic lesion, and an unusual cutaneous manifestation, diagnosed as mid-dermal elastolysis. The latest two, to the best of our knowledge, have been here first described in a case of SAPHO syndrome.

ACR Appropriateness Criteria® Nontraumatic Chest Wall Pain

Chest pain is a common reason that patients may present for evaluation in both ambulatory and emergency department settings, and is often of musculoskeletal origin in the former. Chest wall syndrome collectively describes the various entities that can contribute to chest wall pain of musculoskeletal origin and may affect any chest wall structure. Various imaging modalities may be employed for the diagnosis of nontraumatic chest wall conditions, each with variable utility depending on the clinical scenario. We review the evidence for or against use of various imaging modalities for the diagnosis of nontraumatic chest wall pain. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Complement system deregulation in SAPHO syndrome revealed by proteomic profiling

SAPHO syndrome is an inflammatory disease invading the skin and bones, whose diagnosis has been difficult due to its low incidence and diversified manifestation. We investigated the serum proteomic profile of SAPHO patients to identify key proteins associated with SAPHO syndrome, trying to find clinical biomarkers or functional molecules for this rare disease. Blood samples from 8 SAPHO patients and 8 healthy controls were detected and analyzed using data independent acquisition (DIA) method to identify differentially expressed proteins (DEPs) specific to SAPHO. A total of 57 differentially expressed proteins were identified (p < 0.05, fold change >1.2), in which 27 proteins were upregulated and 30 downregulated. DEPs may participate in GO terms such as "lipid particle" and "Notch signaling pathway", as well as KEGG pathways including "complement and coagulation cascades" and "mTOR signaling pathway". The overexpression of inhibitors of the complement system (CFH and C4BP), were verified in a larger cohort (16 SAPHO patients, 8 AS patients and 24 healthy controls) with ELISA, and the combined diagnostic ability of CFH and C4BP was predicted by ROC curve with an AUC of 0.91, which may be molecular candidates for further study on diagnosis and pathology of this rare disease. SIGNIFICANCE: Our research provided the first insight into plasma proteomic profile for SAPHO patients，offering potential biomarkers for disease diagnosis. We found that inhibitors of complement system such as CFH and C4BP were up-regulated in SAPHO syndrome, which may play important roles in the pathogenesis of SAPHO syndrome.

SAPHO Syndrome Mimicking Infectious Spondylodiscitis and Bone Metastasis

The acronym SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) includes diseases with similar osteoarticular manifestations and skin conditions. Making this diagnosis is not always obvious, especially when the clinical presentation does not fit the typical pattern of the disease or it occurs in a particular field. We described three cases where the diagnosis was difficult. A 46 year-old woman presented with cervical pain. The cervical X-ray showed the aspect of an ivory C5 vertebra. The patient had, however, preserved general condition, no signs of underlying neoplasia, nor other joint complaints. Blood analysis was normal. Tomography did not find any suspect lesion but showed sclerosis and hyperostosis of the manubrium. Scintigraphy showed the characteristic “bullhead” appearance. A 61-year-old woman had thoracic and lumbar pain. MRI showed spondylodiscitis in D3-D4, D4-D5, D5-D6, D6-D7, and L1-L2 with paraspinal soft tissue involvement, simulating infectious spondylodiscitis. Infectious investigations and discovertebral biopsy performed twice were negative. SAPHO syndrome was then suspected. Bone scintigraphy showed uptake in the chondrosternal articulations and D4 to D7 vertebrae. The diagnosis of SAPHO was established. The third case was a 46-year-old man with a lung adenocarcinoma. Staging for metastatic disease, a TAP tomography was performed and showed osteosclerosis of D8 to D12 and intra-articular bridges in the sacroiliac joints. MRI and scintigraphy eliminated malignancy and confirmed the diagnosis of SAPHO. In our cases, imaging findings could facilitate differentiating SAPHO syndrome from other diseases.

Case Report: SAPHO Syndrome Mimicking Bone Metastases During Treatment With Pembrolizumab for Non-small Cell Lung Cancer

A 69-year-old female with recurrent stage IV squamous cell lung carcinoma and metastatic abdominal lymph node but not bone metastases was being treated with pembrolizumab. Four months after starting the recurrent treatment, the tumour reduced in size but she began to complain of back pain and palmar rash. A bone scan showed uptake lesions in the left sternocostal joints and vertebrae, while spine magnetic resonance imaging (MRI) showed multiple lesions in the thoracic vertebrae. Her heterogeneous lesions, such as skin and multiple bone manifestations, were comprehensively diagnosed as SAPHO syndrome by different experts. Furthermore, the SAPHO syndrome was suspected to be an immune-related adverse event induced by pembrolizumab, and pembrolizumab withdrawal and prednisolone treatment were performed. Subsequently, her symptoms improved and the follow-up imaging findings showed that the bone lesions had almost disappeared. This case demonstrates that SAPHO syndrome mimicking bone metastases developed during treatment with pembrolizumab. SAPHO syndrome is rare and bone lesions related to the disease may be misdiagnosed as bone metastases. Therefore, it is important in the future for various physicians to have a better understanding of SAPHO syndrome and to consider the potential relationship between this disease and immunotherapy.

Comparing children and adults with chronic nonbacterial osteomyelitis

PURPOSE OF REVIEW

To describe the main clinical differences of children and adults with chronic nonbacterial osteomyelitis (CNO).

RECENT FINDINGS

CNO is a severe systemic autoinflammatory syndrome characterized by multiple bone lesions because of inflammatory osteitis. Delay to diagnosis of CNO can lead to functional impairment, fractures, and chronic pain. Key clinical aspects and disease patterns differ in children and adults, including onset and time to diagnosis, symptom localization, associated comorbidities (i.e. skin, joints), bone lesion distribution pattern, and treatment approach. Novel biomarkers, such as urine N-terminal telopeptide in children and serum IgG4 in adults, are being studied for possible future use in improving diagnosis and guiding treatment. Despite recent advances in our understanding of CNO, many children and adults have a high disease burden and poor long-term outcomes. Recent findings suggest that adults with CNO tend to have a more chronic disease course and are less likely to achieve remission in follow-up.

SUMMARY

The clinical presentation of CNO differs in children and adults, highlighting the importance of these key features for the accurate diagnosis and early treatment in CNO.

Autoinflammatory syndromes

Autoinflammatory syndromes are a steadily growing group of inflammatory diseases caused by abnormal regulations of the innate immune system. The clinical presentation is multifaceted, but recurrent fever, skin involvement, joint inflammation and other systemic symptoms of inflammation are characteristic. In contrast to classic autoimmune diseases, autoantibodies or specific T cells are not involved in the pathogenesis. In fact, innate immunity plays the most important role in autoinflammation. While activation of the innate immune system is usually self-limiting in healthy individuals, mutations and dysregulation can lead to chronic and excessive activation of innate immune responses and to the development of autoinflammatory diseases.

The Diagnosis and Treatment of Adult Patients with SAPHO Syndrome: Controversies Revealed in a Multidisciplinary International Survey of Physicians

INTRODUCTION

This study aimed to investigate the current practice in the diagnosis and treatment of SAPHO syndrome among the international rheumatology and dermatology communities.

METHODS

We conducted an electronic survey among the members of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA), the Japan Spondyloarthritis, and Israeli Societies of Rheumatology.

RESULTS

A total of 78 physicians participated in the survey: rheumatologists (83%, n = 65), dermatologists (11.5%, n = 9), and orthopedics (3.8%, n = 3). SAPHO was considered a subtype of spondyloarthritis by 48.7% (n = 38), a subtype of psoriatic arthritis by 19.2% (n = 15), a separate entity by 25.6% (n = 20), and a subtype of reactive arthritis by 6.4% (n = 5). Palmoplantar pustulosis was the most prevalent cutaneous manifestation (n = 44, 56.4%) and anterior chest pain-the most prevalent osteoarticular manifestation (n = 66, 84.6%). The majority (84.6%, n = 66) voted for the update of the present diagnostic criteria by Khan 1994. Magnetic resonance imaging was considered the preferred imaging modality for the diagnosis of SAPHO by 41% (n = 32). Conduction of bone biopsy for diagnosis of non-infectious osteitis was supported only by 10.3% (n = 8). Patient-reported outcomes were considered the most appropriate measure for the assessment of disease activity by 47.4% (n = 37). The treatment approach was overall similar among the rheumatology and dermatology communities, including non-steroidal anti-inflammatory drugs, bisphosphonates, conventional disease-modifying anti-inflammatory drugs, and biologics.

CONCLUSIONS

Our study underlines the controversy on diagnosis and treatment of SAPHO syndrome among specialists in rheumatology and dermatology and emphasizes an unmet need for update and validation of diagnostic criteria and treatment approach.

Fibromyalgia in patients with synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome: prevalence and screening

OBJECTIVE

To explore the prevalence, clinical characteristics, and screening strategy for fibromyalgia (FM) in patients with synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome.

METHODS

A total of 313 patients from a cohort of 354 SAPHO patients volunteered to participate in this study. Demographic, clinical and laboratory data were collected at baseline. Acute-phase reactants during the last 3 months were obtained. Patient-reported outcomes (PROs) and FM evaluation were recorded by questionnaires.

RESULTS

A total of 57 (18.2%) patients met the 2016 research criteria for FM. Compared to those without FM, these patients had significantly higher visual analog scale (VAS), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI) scores (all p < 0.001). However, no differences in the erythrocyte sedimentation rate (ESR) or hypersensitive C-reactive protein (hs-CRP) levels were identified between the two groups. Patients with FM were also markedly older [odds ratio (OR) 1.072, p = 0.032] and had higher Fibromyalgia Rapid Screening Tool (FiRST) scores (OR 1.607, p = 0.016). The FiRST score showed a sensitivity of 50.9% and a specificity of 89.8%, and with a cutoff of 3, the FiRST score presented a high sensitivity of 84.2%.

CONCLUSION

The prevalence of FM among SAPHO patients was similar to that among patients with other rheumatic diseases. Concomitant FM in SAPHO syndrome was associated with older age and worse PROs. Different cutoff values for FiRST screening should be used in patients with SAPHO syndrome. Key Points • The prevalence of FM among SAPHO patients was similar to that among patients with other rheumatic diseases. • Concomitant FM in SAPHO syndrome was associated with older age, widespread pain, and worse PROs. • Different cutoff values for FiRST screening should be used in patients with SAPHO syndrome.

Clinical characteristics of pediatric synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome: the first Chinese case series from a single center

INTRODUCTION

Pediatric SAPHO syndrome is regarded as the equivalent of chronic recurrent multifocal osteomyelitis or chronic non-bacterial osteomyelitis. This study aimed to evaluate the clinical features and treatment options for Chinese pediatric patients with SAPHO syndrome.

METHOD

We conducted a single-center, retrospective study on a sample of 24 pediatric patients with SAPHO syndrome who were diagnosed at Peking Union Medical College Hospital from April 2014 to August 2018. The demographic, clinical, laboratory, imaging, histological, and therapeutic data were collected and analyzed.

RESULTS

A total of 15 boys and 9 girls were included. The mean age of onset of bone and skin symptoms was 11.7 ± 3.8 and 14.4 ± 2.7 years, respectively. The mean follow-up period was 39.2 months. Seventeen patients had skin manifestations (46% had severe acne, 100% were boys; 21% had palmoplantar pustulosis, 100% were girls). Bone lesions were localized in four of the following major regions: anterior chest wall (42%), mandible (29%), peripheral bones (50%), and spine and sacroiliac joints (21%). Six patients had been treated with non-steroidal anti-inflammatory drugs, 10 with bisphosphonate, 10 with a tumor necrosis factor-α antagonist, and 1 with glucocorticoids, with variable responses. A total of 70% of the patients had complete remission after bisphosphonate or TNF-α antagonist therapy.

CONCLUSION

Pediatric patients with SAPHO syndrome have different characteristics from other cohorts in the sex ratio, frequency of mandibular involvement, and sex distribution of skin lesions. Bisphosphonate and TNF-α antagonists show a favorable response in pediatric SAPHO syndrome treatment. Key points •Being the first study that describes an Asian pediatric SAPHO case series. •Chinese pediatric patients with SAPHO syndrome have different characteristics from Chinese adult patients and Caucasian pediatric patients.

Synovitis, Acne, Pustulosis, Hyperostosis, Osteitis (SAPHO): An Interesting Clinical Syndrome

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare disorder that classically involves the musculoskeletal system, i.e. bone, joint and skin. The exact pathogenesis of this syndrome is unknown. However, autoimmunity, infections, immune malfunction and genetic factors are attributed to its pathophysiology. Bone and joint involvements are the hallmark of SAPHO syndrome and not necessarily require cutaneous involvement at the time of diagnosis. X-ray of the affected joints could show osteitis with sclerosis. Anterior chest wall involvement particularly ''bullhead appearance'' seen on bone scan is a striking feature of the syndrome. Erythrocyte sedimentation rate (ESR) is usually elevated amongst the majority of patients. Diagnosis of SAPHO is always challenging and often delayed because of a multitude of symptoms. The mainstay of treatment is control of pain and inflammation with both non-steroidal anti-inflammatory drugs (NSAIDs) and rescue courses of systemic steroids. If failed to control symptoms with first-line agents and in those with severe disease, disease-modifying anti-inflammatory drugs (DMARDs) may be needed eventually. Despite a chronic inflammatory condition, it remains stable in the majority of cases. Here in this case report, we reiterate the importance of early recognition, timely diagnosis and prompt treatment initiation.

Axial skeletal lesions and disease duration in SAPHO syndrome: A retrospective review of computed tomography findings in 81 patients

AIMS

To explore the relevance of disease duration with axial skeletal lesions in synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome based on computed tomography (CT).

METHODS

Patients who had undergone whole-spine CT were included from a previously reported single-center cohort of SAPHO syndrome. Patients with previous treatments of bisphosphates, biological agents or surgeries were excluded. Sites of axial skeletal involvement were reviewed including the spine, sacroiliac joints, and anterior chest wall. Duration of osteoarticular involvement was defined as the interval between the onset of osteoarticular symptoms and the CT evaluation.

RESULTS

Eighty-one patients (54 female and 27 male) were included in the study. The mean disease duration was 26.9 ± 34.9 months. Fifty (63.0%) patients showed spinal lesions on CT. The average numbers of involved vertebral segments for corner and endplate lesions were 3.16 ± 3.51 and 0.73 ± 1.85 respectively. Sixty-eight (84.0%) patients exhibited abnormalities in the anterior chest wall. The number of involved vertebral segments showed poor correlation with disease duration for both corner lesions (r²  = 0.051, P = 0.043) and endplate lesions (r²  = 0.137, P = 0.001). Patients with costoclavicular involvement showed remarkably longer disease duration than those without (49.3 ± 47.7 months vs 18.0 ± 23.5 months, P = 0.006), while no significant difference was detected regarding other structures in the anterior chest wall.

CONCLUSION

Costoclavicular involvement is a hallmark of long disease duration in SAPHO syndrome. Corner and endplate lesions in the vertebrae and sacroiliac involvement may not relate to disease course.

Imaging features in patients with SAPHO/CRMO: a pictorial review

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and chronic recurrent multifocal osteomyelitis (CRMO) have been described as disorders of chronic osteoarthritic inflammation frequently associated with skin manifestations, and SAPHO and CRMO (SAPHO/CRMO) are rare autoinflammatory disorders of unknown etiology. SAPHO tends to occur in adults and CRMO predominantly occurs in children and adolescents. SAPHO/CRMO can affect any skeletal region (e.g., anterior chest wall, spine, or long bones). As SAPHO/CRMO are diagnoses of exclusion, the diagnoses might be difficult if skin manifestations are not clearly evident. However, knowledge of the imaging findings of skeletal disorders is helpful for correcting the diagnosis and avoiding unnecessary invasive procedures, as well as in facilitating early diagnosis and adequate treatment. This pictorial review describes the appearance of increased skeletal uptake for SAPHO/CRMO on bone scintigraphy along with findings from radiography, computed tomography, and magnetic resonance imaging.

SAPHO Syndrome Involving the Mandible Treated With 99Tc-MDP

SAPHO (synovitis-acne-pustulosis-hyperostosis-osteitis) syndrome is a chronic inflammatory disease involving multiple organs such as skin and bones. At present, its etiology and pathogenesis are still unclear. Due to the variety of clinical manifestations and the small number of SAPHO syndrome involving the mandible, accurate diagnosis is difficult for oral and maxillofacial surgeons. Here, the authors report that a male patient with SAPHO syndrome involving the maxillofacial skin and mandible, followed for 3 years. We used Tc-MDP (technetium-99 conjugated with methylene disphosphonate) (commercially known as Yunke) to treat this disease and achieved significant clinical treatment. This suggests that Tc-MDP can be used as a bisphosphonate to treat SAPHO syndrome.

Enhanced migration and adhesion of peripheral blood neutrophils from SAPHO patients revealed by RNA-Seq

Background

SAPHO syndrome is a rare disease characterized by inflammatory lesions on skin and bones. Diversified manifestation and inadequate understanding of etiology has limited its diagnosis and treatment. The co-occurrence of other immune-mediated diseases strongly suggests an involvement of autoimmunity in SAPHO syndrome. However, the role of the largest population of circulating immune cells, neutrophils, is still not well explored. In this study, we performed RNA sequencing to profile the mRNA expression of neutrophils purified from peripheral blood of SAPHO patients to identify key genes associated with SAPHO syndrome, trying to find new functional molecules or biomarkers for this rare disease.

Results

A total of 442 differentially expressed genes were identified (p < 0.05, fold change > 2), in which 294 genes were upregulated and 148 genes were downregulated. Five differentially expressed genes of interest were verified by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR), among which S100A12 was upregulated and positively related to high-sensitivity C-reactive protein (hsCRP), while the downregulated gene MYADM was positively related to osteocalcin. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that differentially expressed genes were enriched in “systemic lupus erythematosus” and “ECM-receptor interaction”. Gene ontology (GO) enrichment showed that differentially expressed genes may participate in biological processes such as “cell migration” and “cell adhesion”.

Conclusions

In conclusion, this study provides a first insight into transcriptome characteristics of SAPHO syndrome, indicating an over-active neutrophil recruitment in patients and possibly suggesting molecular candidates for further study on diagnosis and pathology of this disease.

Electronic supplementary material

The online version of this article (10.1186/s13023-019-1169-3) contains supplementary material, which is available to authorized users.

Chronic non-bacterial osteomyelitis: a comparative study between children and adults

BACKGROUND

To compare clinical presentation, diagnostic and treatment strategies, and outcome between pediatric and adult patients with chronic non-bacterial osteomyelitis (CNO).

METHODS

Retrospective single-centre comparative study of pediatric and adult patients diagnosed with chronic recurrent multifocal osteomyelitis (CRMO)/CNO or synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome treated at the Medical University of Graz.

RESULTS

24 pediatric patients diagnosed with CRMO/CNO and 10 adult patients diagnosed with SAPHO syndrome were compared. Median age at diagnosis was 12.3 years (range 7.9-18.9) in the pediatric group and 32.5 years (range 22-56) in the adult group. Median time to diagnosis was shorter in children than in adults (0.3 vs. 1.0 years). Initial clinical presentation, laboratory and histopathological findings were similar in children and adults. Mean numbers of bone lesions were comparable between pediatric and adult patients (3.1 vs. 3.0), as were rates of skin involvement (33% vs. 30%). Sternal involvement was more frequent in adults whereas involvement of clavicle and long bones was more frequent in children (41.7% vs.10, 33% vs. 10%). Computerized tomography (CT) was used more often in adults, whereas whole-body magnetic resonance imaging (MRI) was used only in children. Bisphosphonates were applied more often in children and outcome was better in children than in adults (62.5% vs.30%).

CONCLUSION

Results of our study suggest that CNO/CRMO and SAPHO syndrome in children and adults might represent a single clinical syndrome that needs a similar diagnostic and therapeutic approach.

Imaging for Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis (SAPHO) Syndrome

Multifocal osteomyelitis and synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome constitute a spectrum of disease that includes inflammatory bone lesions and dermatologic findings. Radiographic features resemble those of the spondyloarthropathies with anterior chest wall involvement. Early radiographic findings are osteodestructive with lytic lesions. Bone scintigraphy of the sternoclavicular region classically yields a 'bull's head' pattern of radionuclide uptake. Magnetic resonance imaging (MRI) can demonstrate corner lesions of vertebral bodies. Ultrasound often reveals peripheral enthesitis. Late radiographic features are usually osteoproliferative. PET/CT can identify chronic lesions. Differential diagnostic considerations include osteomyelitis and malignancy, which often prompt bone biopsy.

Clinical features and radiological findings of 67 patients with SAPHO syndrome

OBJECTIVES

The purpose of this study was to facilitate the understanding of the SAPHO (Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis) syndrome by analyzing the clinical and radiological features of 67 Japanese patients with SAPHO syndrome.

METHODS

Sixty-seven Japanese patients (female/male: 44/23, mean age at onset: 48.5 years) were diagnosed with SAPHO syndrome from 2002 to 2013 at our hospital. Medical records and radiological imaging of these patients were retrospectively reviewed.

RESULTS

Among the 67 patients, 41 had dermatological manifestations, such as palmoplantar pustulosis, acne, and psoriasis. Initial symptom was local pain in all patients, and the most common initial site of the symptom was the anterior chest. Bacterial and fungal cultures from 20 bone biopsies were all negative. Histopathological diagnosis of the specimens was non-specific inflammation in all cases. Bone lesions were observed in 65 patients (97.0%). On the other hand, articular lesions including enthesitis were found in 31 patients (46.2%).

CONCLUSION

SAPHO syndrome had different clinical and radiological aspects. The clinical features were not remarkable, except the dermatological manifestations and the involvement of the anterior chest. Bone lesions including hyperostosis and osteitis were found radiographically in the majority of patients with SAPHO syndrome. These are the characteristics of the SAPHO syndrome, with the exclusion of other bone diseases.

SAPHO syndrome associated with hidradenitis suppurativa and pyoderma gangrenosum successfully treated with adalimumab and methotrexate: a case report and review of the literature

SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome is a rare inflammatory condition describing the combination of skin, bone, and joint manifestations that has a heterogeneous presentation. We report a case of severe SAPHO syndrome in association with hidradenitis suppurativa and pyoderma gangrenosum in a 27-year-old male. The patient had an initial migratory arthritis affecting the knees, ankles, metacarpophalangeal joints, proximal interphalangeal joints, wrists, shoulder, and lower back, which progressed to a persistent arthritis and swelling at the sternum, shoulders, wrists, hands, feet, and lower back. Radiographic changes were consistent with the diagnosis of SAPHO syndrome. Serum proinflammatory cytokine levels were significantly elevated and improved substantially after 3 months of therapy. Rationale for therapy in this patient was the observation that tumor necrosis alpha antagonists have been successfully used in SAPHO syndrome, and since arthropathy was so prominent in our patient, we elected to use adalimumab combined with methotrexate.

Pustular Palmoplantar Psoriasis Successfully Treated with Nb-UVB Monochromatic Excimer Light: A Case-Report

Barber’s palmoplantar pustulosis (PPP) is a form of localised pustular psoriasis, affecting the palmar and plantar surfaces. It is a chronic disease, with a deep impact on the patients’ quality of life. The Authors discuss a case of Baber Psoriasis successfully treated with monochromatic excimer light.

Clinical heterogeneity of SAPHO syndrome: challenging diagnose and treatment

Synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome is a rare disease which is often misdiagnosed and under-recognized, because of its peculiar and heterogeneous clinical presentation. Its main features consist of cutaneous and osteoarticular manifestations, the latter affecting more often the anterior chest wall and having typical radiologic findings. There are no validated diagnostic criteria for SAPHO and no guidelines for treatment, due mainly to its rarity; as a consequence, therapy is empirical and aimed to control pain and modifying inflammatory process. To date, the use of anti-TNF agents has been proved to be a valid alternative for patients unresponsive to conventional treatments, such as NSAIDs, corticosteroids, DMARDs and biphosphonates. The clinical heterogeneity of the disease, possibly due to differences in pathogenic mechanism of different manifestations, is challenging for both diagnosis and treatment, which should aim to control both skin and bone involvement in different clinical subsets. Here, we summarize the current status of knowledge about the SAPHO syndrome and present two cases of patients with very different disease manifestations, suggesting the need for personalized treatment.

Bone metabolism and inflammatory characteristics in 14 cases of chronic nonbacterial osteomyelitis

BACKGROUND

Chronic nonbacterial osteomyelitis (CNO) is a multifocal autoinflammatory disease that often impairs daily life in children. This study aimed to investigate the bone metabolic and inflammatory characteristics of patients with CNO, and to assess the differences between responders and nonresponders to conservative treatment.

METHODS

We investigated the clinical symptoms; laboratory data including inflammatory and bone metabolic biomarkers; and imaging findings from plain radiography, magnetic resonance imaging (MRI), fluorodeoxyglucose-positron emission tomography (FDG-PET), and dual-energy x-ray absorption (DEXA) in 14 patients with CNO. All patients underwent first-line treatment comprising systemic nonsteroidal anti-inflammatory drugs with or without bisphosphonate. According to the response to the first-line treatment, the patients were divided into the clinical remission/partial response group and the no response group. The differences in bone metabolic and inflammatory characteristics between the two groups were assessed.

RESULTS

All patients had low bone mineral density assessed with DEXA. The bone metabolic biomarkers (bone-specific alkaline phosphatase and tartrate-resistant acid phosphatase 5b) were increased in boys of all ages and in young girls. Multiple inflammatory regions were detected in all patients by using FDG-PET including asymptomatic regions. The no response group had higher immunoglobulin G (IgG) and a greater number of bone inflammatory lesions detected on MRI than the clinical remission/partial response group.

CONCLUSION

Our data indicate the involvement of abnormal bone turnover, necessity of whole-body scanning, and association of higher serum IgG levels and greater numbers of inflammatory lesions with prolonged disease activity in patients with CNO.

Whole-spine Computed Tomography Findings in SAPHO Syndrome

OBJECTIVE

We evaluated the whole-spine computed tomography (CT) findings in patients with synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome to improve our understanding of this rare disease.

METHODS

Whole-spine CT images obtained in 69 patients with SAPHO were reviewed. For each individual, a total of 25 vertebrae were evaluated for the distribution of affected vertebrae, CT manifestations of vertebral lesions, symmetry and location of distribution of the lesions on vertebrae, involvement pattern, and narrowing of adjacent intervertebral disc space. Paravertebral ligamentous ossifications, apophyseal joint disorders, and costovertebral joint disorders were also evaluated.

RESULTS

All the 69 patients with SAPHO exhibited abnormalities on whole-spine CT. Sixty-four had vertebral lesions, 52 had paravertebral ossifications, and 47 had both. The vertebral lesions were observed in 441 vertebrae, with a predilection for thoracic spine. The lesions exhibited a mixture of cortical erosion, reactive osteosclerosis of surrounding cancellous bone, and syndesmophyte. They may be confined to the vertebral corner (65.1%) or be extensive, involving the endplate (34.9%). Corner lesions could start in any part of the epiphyseal ring. The lesions were asymmetrically distributed. The affected vertebrae were more consecutively involved in a "kissing" appearance (78.2%). Intervertebral disc spaces were usually normal or mildly narrowed. There were 320 foci of paravertebral ossifications observed, with a predilection for the supraspinous ligament. Paravertebral ossifications were delicate and segmental. Ossifications throughout annulus fibrosis and apophyseal joint were not observed.

CONCLUSION

Our investigation of the distributional, morphological features and the involvement pattern of spinal lesions in patients with SAPHO demonstrated distinct CT characteristics.

High prevalence of autoimmune disease in the rare inflammatory bone disorder sternocostoclavicular hyperostosis: survey of a Dutch cohort

BACKGROUND

Sternocostoclavicular hyperostosis (SCCH; ORPHA178311) is a rare inflammatory disorder of the axial skeleton, the precise pathophysiology of which remains to be established. We addressed the potential association of SCCH with autoimmune processes by evaluating the lifetime prevalence of autoimmune disease in 70 patients with adult-onset SCCH and 518 SCCH-unaffected first-degree relatives (parents, siblings and children). Danish hospital registry data for autoimmune diseases were used as reference data.

RESULTS

The mean age of interviewed patients was 56.3 years (range 26-80 years) and 86% were female. Interviewed patients belonged to 63 families, with four families having clusters of 2-3 patients. A diagnosis of at least one autoimmune disease was reported in 20 SCCH patients (29%) and in 47 relatives (9.1%), compared to an estimated 3.9% prevalence of autoimmune disease in the Danish reference population. A diversity of autoimmune diseases was reported in SCCH patients and relatives, most frequently psoriasis vulgaris (14%). Palmoplantar pustulosis was reported by 28 patients (40%). In SCCH patients, inclusion of palmoplantar pustulosis as putative autoimmune disease increased the overall prevalence to 54%.

CONCLUSIONS

The high prevalence of autoimmune disease in patients with sternocostoclavicular hyperostosis and their first-degree relatives suggests that autoimmunity may play a role in the still elusive pathophysiology of the intriguing osteogenic response to inflammation observed in this rare bone disorder.

SAPHO Syndrome: Current Developments and Approaches to Clinical Treatment

SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, and osteitis) is a rare autoimmune disease which, due to its clinical presentation and symptoms, is often misdiagnosed and unrecognized. Its main features are prominent inflammatory cutaneous and articular manifestations. Treatments with immunosuppressive drugs have been used for the management of SAPHO with variable results. To date, the use of anti-TNF-α agents has proved to be an effective alternative to conventional treatment for unresponsive or refractory SAPHO cases. TNF-α is a pro-inflammatory cytokine and pivotal regulator of other cytokines, including IL-1 β, IL-6, and IL-8, involved in inflammation, acute-phase response induction, and chemotaxis. IL-1 inhibition strategies with anakinra have shown efficacy as first and second lines of treatment. In this review, we will describe the main characteristics of biological drugs currently used for SAPHO syndrome. We also describe some of the promising therapeutic effects of ustekinumab, an antibody against the p40 subunit of IL-12 and IL-23, after failure of multiple drugs including anti-TNF-α and anakinra. We discuss the use and impact of the new anti-IL-1 antagonists involved in the IL-17 blockade, in particular for the most difficult-to-treat SAPHO cases.

Multimodal imaging findings of SAPHO syndrome with no skin lesions: A report of three cases and review of the literature

Synovitis, acne, palmoplantar pustulosis, hyperostosis and osteitis syndrome (SAPHO) is a rare syndrome that affects the skin, bones and joints. Diagnosis of SAPHO syndrome is established on clinical appearance and imaging features. The present case report described the imaging features of three cases of SAPHO with sternoclavicular joint arthritis but without skin manifestations using multiple imaging modalities, including computed tomography (CT), magnetic resonance imaging (MRI) and bone scintigraphy. The first case was a 52-year-old male who suffered from progressive sternoclavicular arthritis for 2 years. The second case was a 62-year-old female with arthritis in the larger joints for 5 years, particularly on the right thoracic area. The third case was a 44-year-old male who exhibited a slight bulge accompanied by pain in the upper anterior chest wall for 4 years. All of them lacked cutaneous lesions. CT demonstrated sclerosis and hyperostosis with subchondral erosions in the sternocostoclavicular joints. MRI revealed bone marrow edema that was slightly hypointense on T1-weighted imaging, and hyperintense on T2-weighted imaging. Typical 'bull head' signs were observed in bone scintigraphy images. The present case study demonstrated that SAPHO syndrome should be suspected in patients with multifocal osteitis or arthritis affecting the chest wall that lack skin manifestations. Multimodal imaging modalities in combination are helpful for SAPHO diagnosis.

High-resolution CT of the sternoclavicular joint and first costochondral synchondrosis in asymptomatic individuals

OBJECTIVE

To assess CT features of the sternoclavicular joint (SCJ) and first costochondral junction in asymptomatic patients.

MATERIALS AND METHODS

In 66 patients transverse and coronal oblique high-resolution multiple detector CT images of the SCJ and first costochondral junction were obtained. Images were reviewed by consensus of two radiologists. Joint space width was measured at three levels, and osteophytes, geodes, and erosions were evaluated. Variants and degree of ossification were noted. Statistical analysis consisted of Shapiro-Wilk test, Pearson's test, and paired sample t test.

RESULTS

There were 34 men and 32 women with a mean age of 60 years (age range, 17-98 years). The width of the joint spaces showed a normal distribution. There was no significant difference between the left and right sides. On coronal images the joint space was wider superiorly and on transverse images posteriorly. There was a trend toward decreasing joint space with age, although it did not reach significance (p > 0.05). Clavicular osteophytes were seen in 16 out of 66 patients (24 %) and sternal osteophytes in 16 out of 66 patients. Clavicular geodes were seen in 10 out of 66 patients (15 %) and sternal geodes in 14 out of 66 patients (14 %). No erosions were seen. Clefts of the first costochondral junction were seen in 31 out of 66 patients (47 %).

CONCLUSION

In asymptomatic patients, there is no significant asymmetry of the SCJ. The joint spaces did not significantly decrease with age, although such a trend could be observed. Pronounced joint space narrowing with large geodes and osteophytes was not seen. Clefts of the first costochondral junction are common and not significant.

A case report of severely damaged hip joint caused by SAPHO syndrome treated with 2-stage total hip arthroplasty

INTRODUCTION

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is an increasingly recognized entity. The hip joint is known as a less frequently affected site in SAPHO syndrome, and there has been limited reports about hip joint diseases caused by SAPHO syndrome, and as such adequate treatment for this disease spectrum is still not fully elucidated.

CASE

We describe the case of a 52-year-old man admitted for SAPHO syndrome who went on to be diagnosed with advanced secondary hip arthritis associated with disabling right hip pain. The diagnosis of SAPHO syndrome was delayed; the patient was given a clinical diagnosis of osteomyelitis and treated with prolonged courses of antibiotics and open surgical debridement at previous tertiary health facility. The patient underwent 2-stage joint replacement surgery in our hospital. At 1 year after the surgery, he is well, with minimal right hip pain and the prosthesis is functioning well.

CONCLUSION

This case shows the safety and effectiveness of the 2-stage joint replacement in treating destructive hip disease caused by SAPHO syndrome mimicking infectious arthritis.