SAPHO: has the time come for tailored therapy?

SAPHO syndrome: current clinical, diagnostic and treatment approaches

This review provides an overview of SAPHO (Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis), a rare autoinflammatory disease that primarily affects bones, skin, and joints. We conducted a search on Medline/PubMed using keywords such as SAPHO syndrome, chronic recurrent multifocal osteitis/osteomyelitis, and related terms. SAPHO syndrome is rare, with a reported frequency of 1 in 10,000 in the Caucasian population. However, the actual incidence of SAPHO syndrome is unknown, and the incidence of the disease is likely higher. The pathogenesis of SAPHO syndrome remains incompletely understood. Current evidence suggests that SAPHO results from a complex interplay between immune dysregulation, genetic susceptibility, and environmental factors. It's not clear if SAPHO syndrome is an autoimmune disease or an autoinflammatory disease, but current evidence suggests that it's more likely an autoinflammatory disease because of things like neutrophil hyperactivity, fewer natural killer (NK) cells, high levels of interleukin (IL)-1, and a good response to treatments that block IL-1. Osteo-articular (OA) involvement is a key clinical feature of SAPHO. It affects the anterior chest wall, axial skeleton, peripheral joints, mandible, long bones of the extremities, and pelvis. Dermatological involvement is a common target in SAPHO, with lesions observed in 60-90% of cases. Common skin lesions include psoriasis and acne, with hidradenitis suppurativa and neutrophilic dermatoses being less commonly seen. Other clinical findings include constitutional symptoms caused by systemic inflammation, such as fever, weight loss, and fatigue. There is no specific laboratory finding for SAPHO syndrome. However, during active disease, there may be an increase in positive acute phase markers, such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement levels, mild leukocytosis, and thrombocytosis. Diagnosis is crucial for SAPHO syndrome, which lacks a specific diagnostic finding and is often underrecognized. A comprehensive evaluation of a patient's medical history and physical examination is crucial. Treatment options include non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroids, conventional and synthetic disease-modifying agents (cDMARDs and sDMARDs), biological therapies, bisphosphonates, and antibiotics. Biological treatments have emerged as a viable alternative for SAPHO patients who do not respond to conventional treatments.

Case report: Inflammatory sternoclavicular joint arthritis induced by an immune checkpoint inhibitor with remarkable responsiveness to infliximab

This report describes the case of a 48-year-old woman who presented with sternoclavicular joint arthritis after administration of an immune checkpoint inhibitor (ICI), durvalumab, for small cell lung carcinoma. The onset of arthritis transpired 18 months after the commencement of the ICI therapeutic regimen and demonstrated resilience to glucocorticoid treatment. After excluding infectious aetiologies and metastatic involvement, the patient was diagnosed with ICI-induced arthritis (ICI-IA). Considering the articular implications akin to the SAPHO syndrome, the patient was treated with infliximab, resulting in complete resolution. This finding implies that biological DMARDs can serve as effective interventions for ICI-induced sternoclavicular joint arthritis. Given the heterogeneous nature of its pathogenesis, the selection of therapeutic agents may require customization based on the distinct clinical presentation of each individual case.

Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis (SAPHO) Syndrome with Cutis Verticis Gyrata: Case Report and Review of Literature

SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome is a rare disease clinically characterized by a wide range of cutaneous and osteoarticular manifestations. Here, we report a case of SAPHO syndrome with cutis verticis gyrata (CVG) and investigated the genetic causes in the four members of this pedigree. After failure of conventional treatments, a recombinant human TNF-α receptor II:IgG Fc fusion protein (rhTNFR:Fc, YISAIPU^®) achieved good control of the disease at the 2-year follow-up. We did not identify any pathogenic mutation in this pedigree. We also summarized the clinical and therapeutic characteristics of 83 patients with SAPHO syndrome through the China National Knowledge Infrastructure (CKNI) database from 2016 to 2021. Patients with acne were young and predominantly male. About 45.8% patients were treated with biological therapies or traditional Chinese medicine (TCM), 84.2% of which showed positive effects against cutaneous and osteoarticular manifestations. We report a case of SAPHO syndrome with CVG that was successfully treated with rhTNFR:Fc. Our results reveal the genetic heterogeneity involved. Biologics and TCM are likely alternative options for the treatment of SAPHO syndrome.

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.

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome of femoral neoplasm-like onset: a case-based review

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is an umbrella term covering a constellation of bone lesions and skin manifestations, but has rarely been clarified in the clinic. We report a 28-year-old woman who had initial onset of SAPHO syndrome with involvement of the femur, and she experienced a tortuous diagnostic course. We also performed a literature review of SAPHO syndrome cases involving the femur and summarize several empirical conclusions by integrating previous findings with our case. Furthermore, we propose our perspective that ailment of the skin caused by infection of pathogens might be the first hit for triggering or perpetuating the activation of the immune system. As a result, musculoskeletal manifestations are probably the second hit by crosstalk of an autoimmune reaction. The skin manifestations preceding bone lesions can be well explained. Current interventions for SAPHO syndrome remain controversial, but drugs aiming at symptom relief could serve as the first preference for treatment. An accurate diagnosis and appropriate treatment can cure patients in a timely manner. Although the pathogenesis of SAPHO syndrome remains to be determined, physicians and surgeons still need to heighten awareness of this entity to avoid invasive procedures, such as frequent biopsies or nonessential ostectomy.

Axial Spondyloarthritis: Mimics and Pitfalls of Imaging Assessment

Axial spondyloarthritis (axSpA) is a chronic inflammatory disorder that predominantly involves the axial skeleton. Imaging findings of axSpA can be divided into active changes, which include bone marrow edema, synovitis, enthesitis, capsulitis, and intra-articular effusion, and structural changes, which include erosions, sclerosis, bone fatty infiltration, fat deposition in an erosion cavity, and bone bridging or ankylosis. The ability to distinguish between imaging lesions suggestive of axSpA and artifacts or lesions suggestive of other disorders is critical for the accurate diagnosis of axSpA. Diagnosis may be challenging, particularly in early-stage disease and magnetic resonance imaging (MRI) plays a key role in the detection of subtle or inflammatory changes. MRI also allows the detection of structural changes in the subchondral bone marrow that are not visible on conventional radiography and is of prognostic and monitoring value. However, bone structural changes are more accurately depicted using computed tomography. Conventional radiography, on the other hand, has limitations, but it is easily accessible and may provide insight on gross changes as well as rule out other pathological features of the axial skeleton. This review outlines the imaging evaluation of axSpA with a focus on imaging mimics and potential pitfalls when assessing the axial skeleton.

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.

SAPHO syndrome: the supposed trigger by isotretinoin, the efficacy of adalimumab and the specter of depressive disorder: a case report

Background

SAPHO (synovitis, acne, pustolosis, hyperostosis and osteitis) syndrome is a rare autoinflammatory chronic disorder, presenting with non-infectious osteitis, sterile joint inflammation and skin manifestations including palmoplantar pustolosis and severe acne.

It could be often misdiagnosed for its heterogeneous clinical presentation. Treatment is challenging and, due to the rarity of this syndrome, no randomized controlled clinical trials have been conducted. Empirical treatments, including non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroids, antibiotics and bisphosphonates and disease-modifying anti-rheumatic drugs (DMARDs) could be quite effective. Anti-tumor necrosis factor-alpha (anti-TNF-α) agents and interleukin-1 (IL-1) antagonists have shown promising results in refractory patients. Isotretinoin, commonly used for severe acne, has been rarely described as possible trigger of osteo-articular manifestations, in particular sacroiliitis.

Case presentation

The case of a boy, affected by acne fulminans and depression, who presented with sacroiliitis after a 10-week treatment with isotretinoin is presented. After SAPHO diagnosis, NSAIDs therapy was started but the onset of bilateral gluteal hidradenitis suppurativa required the switch to a TNF-α antagonist (Adalimumab) with the achievement of a good control of the disease. Despite specific therapy with sertraline, the patient continued to complains severe depression.

Conclusions

Our case reports a temporal association between the onset of osteo-articular symptoms and the introduction of isotretinoin, as previously described. However, this timeline is not sufficient to establish a causal role of this drug into the pathogenesis of sacroiliitis. At this regard, further studies are required. The occurrence of hidradenitis suppurativa during SAPHO course supported the introduction of TNF-α blockers with a favourable result, as reported in a few cases in literature. The association between SAPHO syndrome and depressive mood disorders is already reported. Our patient experienced severe depression whose trend seems to be independent from the course of the main disease. Currently, it is not clarified if depression could be considered reactive to the underling disease or if it forms an integral part of the autoinflammatory disorder.

Orofacial manifestations of SAPHO syndrome: a systematic review of case reports

SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome is a poorly known disease with cutaneous and osteo-articular manifestations requiring a multidisciplinary care. The aim of this study was to review the case reports that have described oral manifestations in patients suffering for this syndrome. A systematic review of case reports was performed on PubMed and Science Direct on January 2020 among all the articles dealing with the disease. In vitro, preclinical, and clinical studies have not been included to select only the case reports. Eighteen articles, published between 1999 and 2019, were included. All the patients presented mandibular osteomyelitis or sclerosis, associated with various other symptoms such as trismus, temporomandibular joint arthritis, or dysphagia. The data highlight the high variability in the disease's manifestations between people and also in the treatments applied. Knowing the orofacial signs of the SAPHO syndrome, the dental surgeon has a crucial role in the diagnosis procedure and must take place in the multidisciplinary medical team involved in the patient following. Some care adaptations are needed for oral interventions in these patients, depending on their treatments and their handicap. Key Points • Orofacial manifestations of SAPHO syndrome mainly occur on the mandible. • In cases of mandible sclerosis, decorticalization surgeries may be performed. • Oral care are encouraged, especially the preventive treatments to limit the necessity of surgeries. • The complexity in the management of patients suffering for a SAPHO syndrome concerns the oral manifestations, the patient general health and the treatments he has to take every day.

Successful treatment of synovitis, acne, pustulosis, hyperostosis, and osteitis and paradoxical skin lesions by Tripterygium wilfordii hook f: a case report

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare autoinflammatory disorder without standardized therapy. Anti-tumor necrosis factor (TNF)-α agents, which have been widely used in recent treatment of SAPHO syndrome, may elicit severe paradoxical psoriasiform lesions. Therefore, physicians must reverse the paradoxical skin lesions in affected patients, while improving their clinical symptoms of SAPHO syndrome. Herein, we describe a patient with SAPHO who exhibited TNF-α antagonist-induced paradoxical skin lesions and benefitted from treatment with Tripterygium wilfordii hook f (TwHF). A 58-year-old woman with SAPHO developed paradoxical psoriasiform lesions and exacerbation of primary palmoplantar pustulosis after 7 weeks of etanercept treatment. She then received TwHF treatment, which resulted in rapid and remarkable improvement in her skin lesions and osteoarticular pain. These findings suggest that TwHF might be a suitable treatment option for patients with SAPHO who exhibit TNF-α antagonist-induced paradoxical skin lesions.