Sjögren's syndrome: Challenges of a multifaceted disease

Primary Sjögren’s syndrome (pSS) is a systemic auto-immune disease. Important symptoms of pSS include dryness of the eyes, mouth, and vagina, fatigue, and pain. This thesis focuses on the impact of pSS on sexual function, classification of pSS and treatment of pSS. The first part of the thesis shows that women with pSS experience a worse sexual function compared to healthy women. In the vagina of pSS patients, the number of white blood cells is increased, indicating the presence of a chronic inflammatory process. Furthermore, the number of smooth muscle cells around blood vessels in the vagina of patients is decreased, which may disturb the production of fluid in the vagina.
The new ACR-EULAR classification criteria were designed to classify patients with pSS for inclusion in clinical studies. This thesis shows that the ACR-EULAR criteria can accurately distinguish patients with and without pSS and remain accurate when salivary gland ultrasonography is added to the criteria. Patients with abnormalities on salivary gland ultrasonography show higher disease activity and worse salivary and tear gland function.
The final part of the thesis evaluated the efficacy and safety of new treatments for pSS. A randomised controlled trial showed that treatment with abatacept does not decrease systemic disease activity in pSS patients in general. However, additional analyses should be performed to assess whether abatacept is effective in certain subgroups of pSS patients. A review of literature shows that rituximab is also not effective in all pSS patients, but selected patients may benefit from this treatment.