Lynn M. Petruzzi and Frederick B. Vivino
AORN Journal, Denver, Colorado (March, 2003)

The trigger that initiates the autoimmune events of Sjögren's Syndrome (SS), also known as Sicca Syndrome, remains unknown.

A variety of factors potentially may influence the development of the disease.

Most research indicates that SS and other autoimmune diseases result from the interaction of specific, susceptible genes and environmental agents that fool the immune system into attacking a target organ. In SS, the exocrine or moisture producing glands are attacked.

No single gene causes SS. However, the human leukocyte antigen 5 HLADQZ,DR3 occurs most frequently in Caucasian patients with SS.

Apoptosis (i.e., programmed cell death) of T lymphocytes and salivary acinar epithelial cells is a gene-regulated process that functions abnormally in patients with SS and appears to contribute to glandular destruction.

Indirect evidence suggests that viruses may play a role as the environmental agent. Hormonal changes also may serve as an agent that influences the disease.

An injury to the exocrine gland may initiate SS. As T lymphocytes invade the tissue, cytokines (i.e., inflammatory messengers) are released locally, which perpetuates the immune inflammatory response.

The cytokines may escape into the bloodstream, stimulating other parts of the body to make proteins that result in an increased erythrocyte sedimentation rate (ESR) and increased production of Creactive protein (CRP). T lymphocytes also stimulate B cells, causing antibody formation (e.g., immunoglobulin G [IgG], immunoglobulin A [IgA], immunoglobulin M [IgM], antinuclear antibody [ANA], Sjögren's Syndrome antigen A [SSA], Sjögren's Syndrome antigen B [SSB]).

Eventually the normal glandular tissue is replaced by fibrosed and fatty tissue. The autonomic nerves that send signals to the moisture producing glands also may be damaged.