Contact allergy masquerading as seronegative Sjögren's syndrome.

Primary Sjögren's syndrome is an autoimmune disease that presents with xerostomia and keratoconjunctivitis sicca (due to chronic lymphocytic inflammation of the salivary and lacrimal glands) and in some cases extraglandular features. Patients typically have positive antinuclear, anti-Ro, and anti-La antibodies; however, around 20% to 30% do not and are therefore termed seronegative. We present a case of a 58-year-old woman who was originally diagnosed with seronegative Sjögren's syndrome based on the American-European classification system. She had complete resolution of her clinical features on identification and avoidance of relevant contact allergens. Contact allergy should be considered in the differential diagnosis of seronegative Sjögren's syndrome, especially where atypical features such as facial rash, normal salivary gland imaging, or lichenoid histology exist.