Synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome and acne fulminans: are they part of the same disease spectrum?

Abstract

Conflict of interest: none declared. Synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome describes a clinical condition with both cutaneous and osteoarticular features. Skin features include severe acne, palmoplantar pustulosis, hidradenitis suppurativa and psoriasis. This condition has been described in both adults and children.1 We would like to illustrate the broad spectrum of this syndrome with two cases, which encompass the diagnosis of acne fulminans and highlight the inflammatory osteitis, a fundamental component of this condition that is present in both cases. Patient 1 was a 25‐year‐old man who presented with extensive crusted nodular and pustular lesions on his scalp (Fig. 1a), face and trunk (Fig. 1b), which had been present since the age of 13 years. Treatment with oral antibiotics including tetracyclines, macrolides, flucoxacillin and isotretinoin (1 mg/kg daily for > 1 year) resulted in temporary but unsustained improvement in his skin condition. He has severe scarring and alopecia. He was investigated by the rheumatologists for chronic arthralgia. Bone scintigraphy revealed multiple areas of increased tracer uptake on the midline of the skull, both mandibles, right maxilla, both calcanei and right mid‐foot. Corresponding radiographs showed a lytic lesion on the skull (Fig. 2), and erosive arthropathy at the right first metatarsophalangeal joint. Intravenous pamidronate has not helped to diminish the arthralgia. Methotrexate is being considered by the rheumatologists as a disease‐modifying agent.