Rosai-Dorfman disease with factor XII deficiency.

A 17-year-old female patient presented with chronic symmetrical oligoarthritis of both knees and ankles, xerostomia, xerophthalmia, multiple bilateral lymphadenopathies in the cervical region, and bilateral parotid enlargement with the histological finding of chronic sialoadenitis. She had been already given methotrexate, chloroquine, and corticosteroids with the diagnosis of rheumatoid arthritis (RA) before referral to our outpatient clinic. Because her complaints and the lumps did not remit and she could be classified as neither RA nor primary Sjögren's syndrome (SS) according to 1987 ACR RA criteria or European preliminary criteria for SS, lymph node biopsy was repeated and revealed the diagnosis of Rosai-Dorfman disease (RDD) with the histological findings of histiocytes, phagocyting lymphocytes in enlarged sinuses, and mature plasma cells infiltrating the pulpa. All the medications were stopped after the pathological diagnosis of RDD and consulting with the Division of Hematology. She was reevaluated with magnetic resonance imaging, which showed dense infiltrative areas around knee and ankle joints, and computed tomography that showed a soft tissue mass surrounding the descending aorta and upper part of the abdominal aorta. Activated partial thromboplastin time was found to be prolonged in prebiopsy examinations, and factor XII deficiency was detected after detailed hematological evaluation. The symptoms of joint involvement were relieved with nonsteroidal antiinflammatory drugs. She has been followed-up without medication without obvious clinical or laboratory change. We herein report a patient with RDD mimicking RA and SS. We consider that RDD should be kept in mind especially in patients with resistant symptoms to conventional therapies, younger disease onset, and predominant parotid and lymph node enlargement.