A total of 78 physicians completed the survey, reflecting a response rate of 11.1%. Among the responders, there were 63 (80.7%) adult rheumatologists, two (2.6%) pediatric rheumatologists, eight (10.3%) dermatologists, one (1.3%) double-board certified rheumatologist and dermatologist, three (3.8%) orthopedic surgeons, and one (1.3%) radiologist. There was a wide geographic representation among the responders: North America (
n = 5) and Canada (
n = 1), Europe (
n = 11); Far East: Japan (
n = 26), Korea (
n = 1), Singapore (
n = 1); Middle East: Israel (
n = 23), Turkey (
n = 1), South America (
n = 5), and India (
n = 1). Three responders did not identify their country. Table
1 summarizes the results of the survey based on the geographic region. The majority of the responders (
n = 67, 86%) reported experience in the management of patients with SAPHO. Forty-four responders reported caring for 1–10 SAPHO patients, 14 responders reported caring for 11–20 SAPHO patients, and seven responders reported caring for up to 50 SAPHO patients in total. The annual incidence of 1–5 SAPHO cases/year was reported by the majority (
n = 61, 78.2%). Eight responders (10.3%), mainly from Japan, reported an annual incidence of 6–10 cases/year in their practice. Palmoplantar pustulosis (PPP) was the most prevalent cutaneous.
Table 1
SAPHO survey results presented by geographic regions of the responders
North America and Canada | 6 | PPP 33.3% Acne 16.7% HS 16.7% | Anterior chest 33.3% Peripheral arthritis 16.7% CRMO 33.3% Sacroiliitis 16.7% | MRI 50% XR 16.7% depends on clinical presentation 33.3% | 50% | Not required 50% Not sure 50% | Mainly yes 66% Partially yes 16.7% No 16.7% | 66.7% | | SpA 66.7% Separate entity 16.7% Reactive arthritis 16.7% |
Europa | 11 | PPP 45.5% Acne 27.3% HS 27.3% | Anterior chest 100% | MRI 36.4% Bone scan 27.3% US 18.2% CT 9.1% Clinical 9.1% | 81.8% | Not required 100% | Mainly yes 81.8% Partially yes 18.2% | 72.7% | PRO 54.5% PhRO 18.2% ASDAS 18.2% Inflammatory markers 9.1% | SpA 36.4% PsA 36.4% Separate entity 27.2% |
Middle East (Israel, Turkey) | 24 | PPP 45.8% Acne 37.5% Pustular psoriasis 16.7% | Anterior chest 95.8% Peripheral arthritis 4.2% | MRI 54.2% Bone scan 20.8% CT 20.8% US 4.2% | 50% | Not required 66.7% Required 12.5% Not sure 20.8% | Mainly yes 45.8% Partially yes 50% No 4.2% | 75% | PRO 50% PhRO 16.7% US 12.5% ASDAS 8.3% PRO + PhRO + CRP 12.5% | SpA 45.8% PsA 20.8% Separate entity 33.3% |
South America | 5 | PPP 20% Acne 60% Pustular psoriasis 20% | Anterior chest 60% Peripheral arthritis 20% Sacroiliitis 20% | MRI 20% Bone scan 60% CT 20% | 40% | Not required 40% Required 40% Not sure 20% | Mainly yes 40% Partially yes 60% | 100% | PRO 40% PhRO 20% Inflammatory markers 20% Bone scan 20% | SpA 20% PsA 20% Separate entity 60% |
Far East (Japan, Korea, Singapore) | 28 | PPP 82.1% Acne 17.9% | Anterior chest 89.3% Peripheral arthritis 3.6% Enthesitis 3.6% CRMO 3.6% | MRI 35.7% Bone scan 35.7% CT 21.4% XR 3.6% US 3.6% | 32.1% | Not required 32.1% Required 10.7% Not sure 57.1% | Mainly yes 64.3% Partially yes 35.7% | 96.4% | PRO 53.6% PhRO 10.7% ASDAS 14.3% Inflammatory markers 7.1% US 10.7% Bone scan 3.6% | SpA 64.3% PsA 14.3% Separate entity 14.3% Reactive arthritis 7.1% |
India | 1 | PPP | Enthesitis | MRI | 0 | Not sure | Mainly yes | Yes | PhRO | Reactive arthritis |
Manifestation among all regions (
n = 44, 56.4%), with a particularly high prevalence in Japan (
n = 23, 82.1%), followed by acne (
n = 20, 25.6%), pustular psoriasis (
n = 7, 9%), and rarely hidradenitis suppurativa (
n = 5, 5.1%). Anterior chest pain and swelling (osteitis, hyperostosis, and joint inflammation of the anterior chest bones and joints) was the most prevalent osteoarticular manifestation (
n = 66, 84.6%), followed by peripheral arthritis (
n = 5, 6.4%), sacroiliitis (
n = 2, 2.6%), and enthesitis (
n = 2, 2.6%). Chronic recurrent multifocal osteomyelitis (CRMO) was reported by three responders (3.8%). MRI was considered the preferred imaging modality for SAPHO diagnosis by 41% (
n = 32) of the responders, whereas 26.9% (
n = 21) preferred bone scan, and 19.2% (
n = 15) voted for computerized tomography (CT) scan. Four responders (5.1%) reported using US applied for sternum joints for SAPHO diagnosis. Regarding the indication for bone biopsy to confirm the diagnosis of SAPHO in cases of osteitis or hyperostosis, only 10.3% (
n = 8) supported the conduction of biopsy, whereas 55% (
n = 43) found no need for this test in the diagnostic work-up of SAPHO. A third of the responders (34.6%) were uncertain regarding this item. Whereas 59% (
n = 46) stated that the Khan diagnostic criteria mainly reflected SAPHO cases in their practice, the vast majority (84.6%,
n = 66) still voted for modification and update of these criteria. SAPHO was considered as a subtype of SpA by 48.7% (
n = 38), a subtype of PsA by 19.2% (
n = 15), a separate entity by 25.6% (
n = 20), and reactive arthritis subtype by 6.4% (
n = 5). Patient-reported outcomes, including patient global and pain assessment (VAS), were considered the most appropriate measures for assessment of disease activity by 47.4% (
n = 37), followed by clinical physician disease assessment by 16.7% (
n = 13), Ankylosing Spondylitis Disease Activity Score (ASDAS) by 10.3% (
n = 8), and blood inflammatory markers by 9% (
n = 7). Six (7.7%) responders suggested a follow-up of disease activity by US, 2.6% (
n = 2) by bone scan, and one (1.3%) by MRI. Three responders (3.8%) suggested a combination of clinical, laboratory, and imaging measures for assessment of disease activity and follow-up. The list of preferable medications and treatments used for SAPHO is presented in Table
2. The question related to the treatment approach to SAPHO was formulated as a multiple-choice question, presenting a list of potential therapeutics. Overall, the treatment approach was similar among the rheumatology and dermatology responders. Non-steroidal anti-inflammatory drugs (NSAIDs) were the first choice universally listed by most responders (colchicine was not specifically mentioned), followed in decreasing order of frequency by anti-TNFa biologics, conventional DMARDs, bisphosphonates, other biologics (not specifically named), and finally antibiotics. Remarkably, only Japanese responders (
n = 4) suggested tonsillectomy as an additional mode of treatment. Comparing treatment approaches among different regions, European and Middle East responders reported a significantly more common use of bisphosphonates (63.6%,
n = 7 and 62.5%,
n = 15, respectively) compared to Japanese responders (
n = 11, 39.3%). Whereas 27.3% (
n = 3) of European and 17.8% (
n = 5) of Japanese responders reported the use of antibiotics, none of the Israeli responders used this treatment.
Table 2
Preferences in the treatment choice of SAPHO
NSAIDs | 76.6 |
Glucocorticoids | 32.5 |
Conventional DMARDs | 57.1 |
Bisphosphonates | 48.1 |
Anti-TNF biologic therapy | 75.3 |
Other biologic therapy | 20.8 |
Antibiotic | 14.3 |
Tonsillectomy | 5.1 |
Isotretinoin | 5.2 |
Topical therapy | 10.4 |
Intra-articular steroid injection | 7.8 |