Dryness syndrome is a systemic chronic autoimmune disease that mainly affects the exocrine glands, especially the lacrimal and salivary glands. It is characterized as common in middle-aged and old-aged women, with common manifestations including dry mouth and eyes, enlarged parotid glands, rampant dental caries and systemic damage. It can be divided into primary dry syndrome and secondary dry syndrome. The latter is secondary to other autoimmune diseases.
The cause of desiccation syndrome is still unclear, and may be related to genetics, immunity, viral infection, and sex hormone level. Patients have family aggregation, and there are many kinds of autoantibodies and a large amount of immunoglobulins and immune complexes in the body, and the incidence is significantly higher in women than in men.
Dry mouth
About 70% to 80% of patients have dry mouth, and in severe cases, they need to drink water frequently when they talk, and when they eat solid food, they need to drink water with water or liquid food, and sometimes they need to get up at night to drink water. 50% of patients may have uncontrollable dental caries, and their teeth gradually turn black and then fall out in flakes. The tongue is dry and cracked, and the oral cavity is often infected with mycobacteria. 50% of the patients may have parotitis, which is characterized by alternating painful swelling of the parotid gland and may subside on its own in about 10 days, but sometimes it may remain enlarged.
Dry eyes
Patients may also have dry eyes, foreign body sensation, and few tears due to decreased mucin secretion from the lacrimal glands.
Dryness of other parts Other superficial parts such as skin, nasal mucosa, digestive tract mucosa and vaginal mucosa can be dry due to reduced glandular secretion.
In addition to dryness of the mouth and eyes, patients may also develop systemic symptoms such as weakness and fever. About 2/3 of patients may have systemic damage.
Skin, muscle and joint involvement
Skin manifestations are vasculitis, such as allergic purpura-like rash, mostly in the lower extremities, rice-grain sized red papules with clear borders that do not discolor when pressed, appear in batches, and persist for about 10 days before fading on their own. Patients may have myalgia and non-deforming arthritis or arthralgia.
Respiratory involvement
Most patients have no respiratory symptoms. Mild involvement may result in a dry cough, while severe involvement may result in shortness of breath and chronic bronchitis, interstitial pneumonia, interstitial fibrosis and abnormal pulmonary diffusion.
Digestive system involvement
Gastrointestinal exocrine gland lesions present with atrophic gastritis, decreased gastric acid, and dyspepsia. About 20% of patients have liver damage, which may be associated with primary biliary cirrhosis or autoimmune hepatitis.
Renal involvement
About 30% to 50% of patients have renal damage, which may include subclinical tubular acidosis, type Ι tubular acidosis, glomerulonephritis, or even renal failure. Clinical manifestations may include hypokalemic muscle paralysis and proteinuria.
Neurological involvement
Peripheral or central nerve damage, such as seizures and peripheral sensory abnormalities, occurs in about 5% of patients.
Hematologic involvement
Decreases in white blood cells, hemoglobin and platelets may occur. Patients with a significant decrease in platelets may have a tendency to bleed. The incidence of lymphoma in patients with this disease is about 44 times higher than normal, and may be combined with non-Hodgkin’s lymphoma and multiple myeloma.
If the above symptoms occur, please go to the rheumatology department in time. To further confirm the diagnosis of dry syndrome, relevant serum immunological tests, oral or ophthalmic examinations are needed. Once diagnosed, treatment should be standardized. The course of this disease is slow and the prognosis is good, and most of the disease can be controlled to achieve remission after proper treatment. Among the systemic damages, those with progressive pulmonary fibrosis, central neuropathy, glomerular damage with renal insufficiency and malignant lymphoma have poorer prognosis, so it is important to seek medical treatment as early as possible to control the disease in the cradle.