Sjögren's syndrome

Overview

Sjögren's syndrome is a chronic autoimmune disorder primarily affecting the body's exocrine glands—especially the salivary and lacrimal glands—leading to symptoms of dry mouth (xerostomia) and dry eyes (keratoconjunctivitis sicca). It occurs when the immune system mistakenly attacks these moisture-producing glands, reducing their function. The condition can exist as a primary disorder or secondary to other autoimmune diseases such as rheumatoid arthritis or systemic lupus erythematosus. Apart from glandular involvement, Sjögren's syndrome can affect multiple organs and systems, including the lungs, kidneys, skin, nerves, and joints. It predominantly affects middle-aged women, with a female-to-male ratio of approximately 9:1.

Causes

The exact cause of Sjögren’s syndrome remains unknown, but it is believed to result from a combination of genetic, environmental, and hormonal factors. The immune system, in genetically susceptible individuals, becomes dysregulated and begins attacking the body’s own tissues.

Contributing Factors:

• Genetic predisposition: Variants in HLA-DR and HLA-DQ genes are associated with higher risk

• Environmental triggers: Viral infections (e.g., Epstein-Barr virus, cytomegalovirus) may initiate the autoimmune response

• Hormonal influences: Estrogen may play a role, given the strong female predominance

In many cases, the syndrome is associated with other autoimmune conditions, leading to a "secondary" classification.

Symptoms

The hallmark symptoms of Sjögren’s syndrome relate to dryness, but systemic features are also common. Symptoms can range from mild to severe and may evolve over time.

Glandular (Sicca) Symptoms:

• Dry eyes: Gritty, burning, or itchy sensation in the eyes; redness; blurred vision

• Dry mouth: Difficulty swallowing or speaking, frequent need to sip water, dental caries, oral infections

Systemic (Extraglandular) Symptoms:

• Fatigue and malaise

• Joint pain and stiffness (non-erosive arthritis)

• Swollen salivary glands, especially the parotids

• Skin dryness or rashes

• Vaginal dryness and dyspareunia in women

Less Common but Serious Manifestations:

• Peripheral neuropathy (numbness, tingling, or burning sensations)

• Interstitial lung disease

• Kidney involvement (e.g., interstitial nephritis)

• Vasculitis and purpura

• Increased risk of lymphoma, particularly marginal zone B-cell lymphoma

Diagnosis

Diagnosis of Sjögren’s syndrome involves a combination of clinical evaluation, laboratory tests, imaging studies, and sometimes biopsy. There is no single definitive test, and diagnosis may be delayed due to symptom overlap with other conditions.

Diagnostic Criteria Include:

• Symptom assessment: Dryness of eyes and mouth, fatigue, joint pain

• Ophthalmologic tests:

  • Schirmer’s test: Measures tear production

  • Rose Bengal or fluorescein staining: Evaluates corneal damage

• Salivary gland tests:

  • Unstimulated salivary flow rate

  • Salivary gland scintigraphy or sialography

• Blood tests:

  • Anti-Ro/SSA and Anti-La/SSB antibodies

  • Positive ANA and rheumatoid factor (RF)

  • Elevated ESR or low complement levels

• Lip (minor salivary gland) biopsy: To assess for lymphocytic infiltration and confirm diagnosis

Classification criteria established by the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) aid in standardizing diagnosis for research and clinical practice.

Treatment

There is no cure for Sjögren’s syndrome, but treatment is aimed at relieving symptoms, preventing complications, and managing systemic involvement. Treatment plans are tailored to the individual and often involve a multidisciplinary approach.

Symptom Management:

• Dry eyes: Artificial tears, lubricating ointments, punctal plugs, cyclosporine (Restasis)

• Dry mouth: Saliva substitutes, sugar-free gum or lozenges, pilocarpine or cevimeline to stimulate saliva production

• Dental care: Regular dental visits, fluoride treatments, and meticulous oral hygiene

Systemic Therapy:

• Nonsteroidal anti-inflammatory drugs (NSAIDs) for joint pain

• Hydroxychloroquine for fatigue, arthritis, and cutaneous symptoms

• Corticosteroids and immunosuppressants (e.g., methotrexate, azathioprine) for severe systemic disease

• Rituximab or other biologics in cases of severe extraglandular involvement or lymphoma

Lifestyle and Supportive Care:

• Hydration and humidifiers to reduce dryness

• Smoking cessation

• Exercise and pacing for fatigue

• Psychological support for chronic illness management

Prognosis

The prognosis for individuals with Sjögren’s syndrome varies depending on the severity of symptoms and extent of systemic involvement. For many, the disease remains stable and manageable with symptomatic treatment. However, some patients experience progressive disease and complications such as:

• Recurrent eye and mouth infections

• Severe fatigue and reduced quality of life

• Organ involvement, particularly lungs, kidneys, and nervous system

• An increased lifetime risk of non-Hodgkin lymphoma (approximately 5–10%)

With appropriate medical care and regular monitoring, most patients can lead active, fulfilling lives. Early diagnosis, regular follow-up, and individualized treatment are key to managing symptoms and minimizing long-term complications.