SAPHO syndrome includes a variety of inflammatory bone disorders that may be associated with skin changes. These diseases share some clinical, radiologic, and pathologic characteristics. An entity initially known as

chronic recurrent multifocal osteomyelitis Chronic recurrent multifocal osteomyelitis (CRMO) is a rare condition (1:1,000,000), in which the bones have lesions, inflammation, and pain. It is called ''multifocal'' because it can appear in different parts of the body, primarily bones, and ...

was first described in 1972. Subsequently, in 1978, several cases of were associated with blisters on the palms and soles ( palmoplantar pustulosis). Since then, a number of associations between skin conditions and osteoarticular disorders have been reported under a variety of names, including sternocostoclavicular

hyperostosis Hyperostosis is an excessive growth of bone. It may lead to exostosis. It occurs in many musculoskeletal disorders. See also * Diffuse idiopathic skeletal hyperostosis * Hyperostosis frontalis interna Hyperostosis frontalis interna is a comm ...

, pustulotic arthro-osteitis, and acne-associated

spondyloarthropathy Spondyloarthropathy or spondyloarthrosis refers to any joint disease of the vertebral column. As such, it is a class or category of diseases rather than a single, specific entity. It differs from spondylopathy, which is a disease of the vertebra ...

. The term SAPHO (an acronym for synovitis, acne, pustulosis, hyperostosis, osteitis) was coined in 1987 to represent this spectrum of inflammatory bone disorders that may or may not be associated with dermatologic pathology.

Diagnosis

Radiologic findings

* Anterior chest wall (most common site, 65–90% of patients): Hyperostosis, sclerosis and bone hypertrophy especially involving the sternoclavicular joint, often with a soft tissue component. * Spine (33% of patients): Segmental, usually involving the thoracic spine. The four main presentations include spondylodiscitis, osteosclerosis, paravertebral ossifications, and sacroiliac joint involvement. * Long bones (30% of patients): usually metadiaphyseal and located in the distal femur and proximal tibia. It looks like chronic osteomyelitis but will not have a sequestrum or abscess. * Flat bones (10% of patients): mandible and ilium. Peripheral arthritis has been reported in 92% of cases of SAPHO as well. In children, the SAPHO syndrome is most likely to affect the

metaphysis The metaphysis is the neck portion of a long bone between the epiphysis and the diaphysis. It contains the growth plate, the part of the bone that grows during childhood, and as it grows it ossifies near the diaphysis and the epiphyses. The met ...

of long bones in the legs (tibia, femur, fibula), followed by clavicles and spine.

Treatment

Bisphosphonate therapy has been suggested as a first-line therapeutic option in many case reports and series. Treatment with tumor necrosis factor alpha antagonists (

TNF inhibitor A TNF inhibitor is a pharmaceutical drug that suppresses the physiologic response to tumor necrosis factor (TNF), which is part of the inflammatory response. TNF is involved in autoimmune and immune-mediated disorders such as rheumatoid arthritis ...

s) has been tried in a few patients with limited success. Other drugs that are used in

psoriatic arthritis Psoriatic arthritis is a long-term inflammatory arthritis that occurs in people affected by the autoimmune disease psoriasis. The classic feature of psoriatic arthritis is swelling of entire fingers and toes with a sausage-like appearance. ...

, to which SAPHO syndrome is closely related, have also been used in this condition. They include NSAIDs,

corticosteroids Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are in ...

sulfasalazine Sulfasalazine, sold under the brand name Azulfidine among others, is a medication used to treat rheumatoid arthritis, ulcerative colitis, and Crohn's disease. It is considered by some to be a first-line treatment in rheumatoid arthritis. It is ...

methotrexate Methotrexate (MTX), formerly known as amethopterin, is a chemotherapy agent and immune-system suppressant. It is used to treat cancer, autoimmune diseases, and ectopic pregnancies. Types of cancers it is used for include breast cancer, leuke ...

ciclosporin Ciclosporin, also spelled cyclosporine and cyclosporin, is a calcineurin inhibitor, used as an immunosuppressant medication. It is a natural product. It is taken orally or intravenously for rheumatoid arthritis, psoriasis, Crohn's diseas ...

and

leflunomide Leflunomide, sold under the brand name Arava among others, is an immunosuppressive disease-modifying antirheumatic drug ( DMARD), used in active moderate-to-severe rheumatoid arthritis and psoriatic arthritis. It is a pyrimidine synthesis inhibi ...

. Some patients have responded to

antibiotics An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention ...

. The rationale for their use is that

Cutibacterium acnes ''Cutibacterium acnes'' (formerly ''Propionibacterium acnes'') is the relatively slow-growing, typically aerotolerant anaerobic, gram-positive bacterium (rod) linked to the skin condition of acne; it can also cause chronic blepharitis and endopht ...

, a bacterium known for its role in acne, has been isolated from bone biopsies of SAPHO patients.

References

External links

{{Disorders of skin appendages Ailments of unknown cause Acneiform eruptions Rheumatology Syndromes

Diagnosis

Radiologic findings

Treatment

See also

References

Further reading

External links