SAPHO syndrome

SAPHO syndrome
Synonyms	N/A
Pronounce	N/A
Specialty	N/A
Symptoms	Osteitis, pustulosis, acne, hyperostosis, synovitis
Complications	Chronic pain, joint dysfunction
Onset	Variable
Duration	Chronic
Types	N/A
Causes	Unknown
Risks	Genetic predisposition, environmental factors
Diagnosis	Clinical evaluation, imaging studies
Differential diagnosis	N/A
Prevention	N/A
Treatment	NSAIDs, antibiotics, bisphosphonates, biologics
Medication	N/A
Prognosis	Variable
Frequency	Rare
Deaths	N/A

SAPHO syndrome is a rare chronic disease characterized by a combination of skin and musculoskeletal manifestations. The acronym SAPHO stands for Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis. This syndrome is considered part of the spectrum of spondyloarthropathies.

Epidemiology

SAPHO syndrome is a rare condition, with an estimated prevalence of 1 in 10,000 individuals. It can occur at any age but is most commonly diagnosed in adults between the ages of 30 and 50. There is no clear gender predilection, although some studies suggest a slight female predominance.

Etiology

The exact cause of SAPHO syndrome is unknown. It is believed to result from a combination of genetic, immunological, and environmental factors. Some studies have suggested a possible association with Propionibacterium acnes, a bacterium commonly found in acne lesions. Genetic predisposition may also play a role, as some patients have a family history of similar conditions.

Pathophysiology

SAPHO syndrome involves both inflammatory and osteoblastic processes. The inflammation primarily affects the synovium and bone, leading to synovitis and osteitis. Hyperostosis, or excessive bone growth, is another hallmark of the syndrome. The skin manifestations, such as pustulosis and acne, are thought to be related to the underlying inflammatory process.

Clinical Features

The clinical presentation of SAPHO syndrome is highly variable. Common features include:

• Synovitis: Inflammation of the synovial membrane, often affecting the sternoclavicular joint.
• Acne: Severe acne can be a prominent feature, particularly in younger patients.
• Pustulosis: Palmoplantar pustulosis is a common skin manifestation, characterized by sterile pustules on the palms and soles.
• Hyperostosis: Abnormal bone growth, often affecting the anterior chest wall, spine, and pelvis.
• Osteitis: Inflammation of the bone, commonly seen in the clavicle, spine, and long bones.

Diagnosis

The diagnosis of SAPHO syndrome is primarily clinical, based on the characteristic combination of skin and musculoskeletal symptoms. Imaging studies, such as X-rays, CT scans, and MRI, can help identify hyperostosis and osteitis. Bone scintigraphy may show increased uptake in affected areas. Laboratory tests are generally non-specific but may show elevated inflammatory markers such as C-reactive protein and erythrocyte sedimentation rate.

Differential Diagnosis

SAPHO syndrome should be differentiated from other conditions with similar presentations, including:

• Psoriatic arthritis
• Ankylosing spondylitis
• Chronic recurrent multifocal osteomyelitis
• Behçet's disease

Treatment

There is no cure for SAPHO syndrome, and treatment is aimed at managing symptoms and improving quality of life. Options include:

• Nonsteroidal anti-inflammatory drugs (NSAIDs): First-line treatment for pain and inflammation.
• Antibiotics: Such as azithromycin, may be used in cases with suspected bacterial involvement.
• Bisphosphonates: Can help manage bone pain and hyperostosis.
• Biologic agents: Such as TNF inhibitors, may be considered in refractory cases.
• Corticosteroids: Used for severe inflammatory episodes.

Prognosis

The prognosis of SAPHO syndrome is variable. Some patients experience mild symptoms with long periods of remission, while others may have chronic, debilitating pain and joint dysfunction. Early diagnosis and appropriate management can improve outcomes.

Research Directions

Ongoing research is focused on better understanding the pathogenesis of SAPHO syndrome and developing targeted therapies. Genetic studies and investigations into the role of microbiota are areas of active interest.

See Also

• Spondyloarthropathy
• Chronic recurrent multifocal osteomyelitis

External Links

• Orphanet: SAPHO syndrome
• PubMed Central: SAPHO syndrome articles

Rheumatologic diseases

Arthritis is often used to refer to any disorder that affects the joints. Rheumatic diseases usually affect joints, tendons, ligaments, bones, and muscles. Rheumatologic diseases usually affect joints, tendons, ligaments, bones, and muscles.

Connective Tissue Diseases

Rheumatology and	Connective Tissue Diseases
Ankylosing spondylitis	Arthritis
Arthritis and Rheumatic diseases	Autoimmune diseases
Autoinflammatory diseases	Behçet’s disease
Bursitis	Giant cell arteritis
Gout	Juvenile arthritis
Knee problems	Lupus
Osteoarthritis	Polymyalgia rheumatica
Psoriatic arthritis	Reactive arthritis
Rheumatoid arthritis	Scleroderma
Sjögren’s syndrome	Systemic lupus erythematosus (Lupus)
Tendinitis	Rheumatologic diseases