Sjögren's Syndrome vs. Lupus: Key Differences in Autoimmune Disease

Both are systemic autoimmune diseases, but they differ in primary targets, symptom patterns, and typical demographics.

Sjögren's Syndrome

• Primary target: Exocrine glands (lacrimal, salivary)
• Hallmark symptoms: Dry eyes (keratoconjunctivitis sicca), dry mouth (xerostomia)
• Systemic features: Fatigue, joint pain, neuropathy, interstitial lung disease, renal tubular acidosis, lymphoma risk (5–10%)
• Demographics: 9:1 female:male, peak 40s–50s
• Antibodies: Anti-SSA/Ro, Anti-SSB/La, ANA, RF

Systemic Lupus Erythematosus (SLE)

• Primary target: Multi-organ (skin, joints, kidneys, CNS, serous membranes, blood cells)
• Hallmark symptoms: Malar rash, photosensitivity, oral ulcers, arthritis, nephritis, cytopenias, serositis, neuropsychiatric
• Demographics: 9:1 female:male, peak 15–45, higher in Black, Hispanic, Asian women
• Antibodies: Anti-dsDNA, anti-Smith, antiphospholipid, ANA (near 100%)

Overlap & Coexistence

• ~15–20% of SLE patients have secondary Sjögren's
• Both can cause fatigue, arthralgia, Raynaud's, positive ANA
• Distinct classification criteria (ACR/EULAR for each)

Management Differences

• Sjögren's: Symptomatic (artificial tears, saliva substitutes), hydroxychloroquine for systemic, rituximab for severe
• SLE: Hydroxychloroquine (all), immunosuppressants (MMF, azathioprine, cyclophosphamide) for organ involvement, belimumab, anifrolumab

Accurate diagnosis guides monitoring (e.g., renal in SLE, lymphoma in Sjögren's) and therapy.