Pseudoxanthoma elasticum masquerading as Sjögren's syndrome.

Pseudoxanthoma elasticum is an inherited disorder of abnormal calcification of elastic fibers in the skin, retina, and cardiovascular system. Herein, we report a patient who had dry eyes and mouth, keratoconjunctivitis sicca, and a low titer ANA at presentation. A lip biopsy was performed to confirm a clinical suspicion of Sjögren's syndrome; however, the histologic findings were diagnostic of pseudoxanthoma elasticum. Antibodies to Ro and La were negative. Subsequently, she was found to have skin and eye findings consistent with pseudoxanthoma elasticum. Although a causal relationship between keratoconjunctivitis sicca and pseudoxanthoma elasticum is not proven, salivary gland involvement with pseudoxanthoma elasticum may explain this patient's symptoms. Physicians should consider the diagnosis of pseudoxanthoma elasticum in patients who present with sicca symptoms without obvious cause, especially if cutaneous or ophthalmologic abnormalities, or both, are present. Careful monitoring for associated problems is needed as soon as pseudoxanthoma elasticum is diagnosed.