Treatment and monitoring of SAPHO syndrome: a systematic review

BACKGROUND AND OBJECTIVES

Synovitis acne pustulosis hyperostosis osteitis (SAPHO) is a rare heterogeneous disease of unknown aetiopathology. Externally validated and internationally agreed diagnostic criteria or outcomes and, as a result, prospective randomised controlled trials in SAPHO are absent. Consequently, there is no agreed treatment standard. This study aimed to systematically collate and discuss treatment options in SAPHO.

METHODS

Following 'Preferred Reporting Items for Systematic Reviews and Meta-Analyses' guidance, a systematic literature search was conducted using PubMed, Scopus and Web of Science databases. Prospective clinical studies and retrospective case collections discussing management and outcomes in SAPHO involving five or more participants were included. Articles not published in English, studies not reporting defined outcomes, and studies solely relying on patient-reported outcomes were excluded.

RESULTS

A total of 28 studies (20 observational, 8 open-label clinical studies) reporting 796 patients of predominantly European ethnicity were included. Reported therapies varied greatly, with many centres using multiple treatments in parallel. Most patients (37.1%) received non-steroidal anti-inflammatory drugs alone or in combination. Bisphosphonates (22.1%), conventional (21.7%) and biological (11.3%) disease-modifying antirheumatic drugs were the next most frequently reported treatments. Reported outcomes varied and delivered mixed results, which complicates comparisons. Bisphosphonates demonstrated the most consistent improvement of osteoarticular symptoms and were associated with transient influenza-like symptoms. Paradoxical skin reactions were reported in patients treated with TNF inhibitors, but no serious adverse events were recorded. Most treatments had limited or mixed effects on cutaneous involvement. A recent study investigating the Janus kinase inhibitor tofacitinib delivered promising results in relation to skin and nail involvement.

CONCLUSIONS

No single currently available treatment option sufficiently addresses all SAPHO-associated symptoms. Variable, sometimes descriptive outcomes and the use of treatment combinations complicate conclusions and treatment recommendations. Randomised clinical trials are necessary to generate reliable evidence.

Successful treatment of pustulotic arthro-osteitis with amoxicillin: A case report and review of the literature

Palmoplantar pustulosis (PPP) is a chronic skin inflammatory disease characterized by sterile pustules on the palms and soles. Pustulotic arthro-osteitis (PAO) is a major comorbidity of PPP, frequently affecting the anterior chest wall. PPP and PAO are thought to be closely associated with focal infection. We report a female in her 40s who developed pustules on her palms and soles with tenderness of both sternoclavicular and left sacroiliac joints, which were not improved with non-steroidal anti-inflammatory drugs. Of note, she showed a great response to amoxicillin, resulting in the almost complete resolution of her skin lesions and arthralgia. We also reviewed previous reports to learn more about the potential therapeutic options of antibiotics for PAO.

An update on therapeutic options for palmoplantar pustulosis: a narrative review and expert recommendations

INTRODUCTION

Palmoplantar pustulosis (PPP) is a chronic inflammatory skin disease belonging to the localized form of pustular psoriasis. It is characterized by sterile pustule formation in palms and soles and a recurrent disease course. Although we have many treatments for PPP, there is no authoritative guidance.

AREAS COVERED

A thorough search of PubMed was conducted to identify studies in PPP from 1973 onwards, with additional references to specific articles. Any treatment methods were outcomes of interest, including topical treatment, systemic treatment, biologics, other targeted treatments, phototherapy, and tonsillectomy.

EXPERT OPINION

Topical corticosteroids are suggested as first-line therapy. Oral acitretin has become the most applied systemic retinoid recommended in PPP without joint involvement. For patients with arthritis, immunosuppressants like cyclosporin A and methotrexate are more recommended. UVA1, NB-UVB, and 308-nm excimer laser are effective phototherapy options. The combinations of topical or systemic agents and phototherapy may enhance the efficacy, particularly in recalcitrant cases. Secukinumab, ustekinumab, and apremilast are the most investigated targeted therapies. However, heterogeneous reported outcomes in clinical trials provided low-to-moderate quality evidence of their efficacy. Future studies are required to address these evidence gaps. We suggest managing PPP based on the acute phase, maintenance phase, and comorbidities.

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 and Pustulotic Arthro-Osteitis (PAO)

Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis (SAPHO) syndrome is a rare inflammatory osteo-articular disorder, which encompassed many diseases, including pustulotic arthro-osteitis (PAO). Bone and joint manifestations, including osteitis, synovitis and hyperostosis, are the hallmark of the SAPHO syndrome and affect a variety of regions of the body. Recent GRAPPA survey indicated that more than 80 percent of cases of SAPHO syndrome in Japan were thought to be PAO, originally proposed by Sonozaki et al. in 1981, whereas severe acne was the most commonly reported skin ailment amongst participants with SAPHO syndrome in Israel. SAPHO syndrome is a rare disease and adequate data regarding its prevalence remains unavailable, whereas prevalence of PPP was reported to be 0.12 % in Japan and 10-30% of patients with PPP had PAO. SAPHO syndrome and PAO are predominantly found in patients in the third through fifth decades of life, and a female predominance are seen in both groups. The diagnosis of SAPHO syndrome/PAO is typically made by a rheumatologist or dermatologist. Identification of a variety of the clinical, radiological, and laboratory features outlined, as well as diagnostic criteria, are used to make the diagnosis. Goals for treating patients with SAPHO syndrome/PAO seek to maximize health-related quality of life by improving skin and articular symptoms, preventing structural changes and destruction, and normalizing physical function and social participation. Finally, we review the non-pharmacological (ie: smoking cessation and controlling focal infections) and pharmacological managements including NSAIDs, bisphosphonates, cs DMARDs, bDMARDs, and other treatments for SAPHO syndrome/PAO.

Anti-Inflammatory Effects of Potassium Iodide on SDS-Induced Murine Skin Inflammation

Potassium iodide (KI), initially derived from seaweed in the early 19th century, is used for treating sporotrichosis in dermatological practice. KI has also been used to treat several noninfectious inflammatory skin diseases. However, the mechanisms underlying the improvement in such skin diseases remain unknown, and KI is not used widely. Thus, although KI is an old drug, physicians may not prescribe it frequently because they lack knowledge about it. Although KI is very inexpensive and causes few side effects, it has been superseded by new powerful and expensive drugs, such as biological agents. We applied 3% KI topically to areas of inflammation induced by SDS in mice. The levels of IL-1 and TNF-α gene expression were reduced, whereas that of IL-10 gene expression was increased. Small interfering RNA that was designed to reduce IL-10 gene expression levels was injected into the same mice, and the anti-inflammatory effects of KI were not observed. Thus, the pharmacologic action of KI is based on its anti-inflammatory effects caused by the increase in IL-10 levels. This information would increase dermatologists' awareness of KI as an efficacious and cost-effective treatment.