Sjögren Syndrome

Key Features

Essentials of Diagnosis

• Dryness of eyes and dry mouth (sicca components); they occur alone or with rheumatoid arthritis or other connective tissue disease

• Rheumatoid factor and antinuclear autoantibodies common

• Increased incidence of lymphoma

General Considerations

• A systemic autoimmune disorder

• Clinical presentation is usually dominated by dryness of the eyes and mouth due to immune-mediated dysfunction of the lacrimal and salivary glands

• Can occur in isolation ("primary" Sjögren syndrome) or in association with another rheumatic disease, most frequently rheumatoid arthritis

Associated conditions

• Rheumatoid arthritis

• Systemic lupus erythematosus (SLE)

• Primary biliary cirrhosis

• Systemic sclerosis (scleroderma)

• Polymyositis

• Autoimmune (Hashimoto) thyroiditis

• Polyarteritis

• Interstitial pulmonary fibrosis

Demographics

• Predominantly a disease of women, with a female:male ratio of 9:1

• Greatest incidence between ages 40 and 60 years

Clinical Findings

Symptoms and Signs

• Eyes

  • Ocular burning, itching, ropy secretions

  • "Grain of sand in the eye" sensation

• Parotid glands

  • Enlargement may be chronic or relapsing

  • Develops in one-third of patients

• Dryness of the mouth (xerostomia) leads to difficulty in swallowing dry foods (like crackers), to constant thirst for fluids, and to severe dental caries

• There may be loss of taste and smell

• Systemic manifestations

  • Dysphagia, pancreatitis

  • Pleuritis, obstructive airways disease and interstitial lung disease (in the absence of cigarette smoking)

  • Neuropsychiatric dysfunction

  • Small vessel vasculitis

• Kidney

  • Renal tubular acidosis (type I, distal) occurs in 20% of patients

  • Chronic interstitial nephritis, which may result in impaired kidney function, may be seen

Differential Diagnosis

• Sicca complex associated with other autoimmune disease, eg, sarcoidosis, rheumatoid arthritis, SLE, systemic sclerosis

• Other causes of dry mouth or eyes, eg, anticholinergics, mumps, irradiation, seasonal allergies, irritation from smoking

• IgG₄-related systemic disease

Diagnosis

Laboratory Tests

• Rheumatoid factor is found in 70% of patients

• Antibodies against SS-A and SS-B (also called Ro and La, respectively) are often present (Table 20–7)

• When SS-A antibodies are present, extraglandular manifestations are far more common