Syndrome / Disease
by drdoc on-line
Who should be treated
Sjogrens disease is a disorder of glandular tissue of the body with resulting dryness of the eyes, mouth and other mucosal tissues. It is associated with lymphatic cell infiltration of the glands and developement of antibodies as part of an autoimmune process.
The cause is primarily autoimmune where the body reacts to it's own tissue, promoted by genetic and environmental factors.In the presence of an already established autoimmune disease, the process is called Secondary Sjogrens syndrome, but if there is no such process, than the condition is called Primary Sjogrens syndrome. Autoimmune diseases that may be associated with Sjogrens include Rheumatoid Arthritis, Lupus or systemic sclerosis, amongst others.
The disease was first described in the 19th century by Mikulicz, hadden and Leber, but was subsequently associated as part of a more general disease with dry eye, and mouth, as well as glandular enlargement and arthritis. A Swedish Ophthalmologist named Sjogren, recognized and described the pattern of dry eye and other features of eye involvement with the systemic disease.
The disease is seen more in females, in the 30's-40's, but can occur in children as well. Secondary sjogrens is seen in 25% of rheumatoid patients. It is also common in scleroderma and lupus. In primary Sjogrens, with no other autoimmune disease, the syndrome is seen in 2% of the general population, especially with increasing age.
The patient usually complains of a slowly progressive dryness of the eyes, with a feeling of grittiness - especially in the morning on waking. Tear production is reduced. The eyes then develop a secondary inflammation of the conjunctiva and cornea, with poor healing and erosion of the superficial layers of the eye. Red eye results, followed by corneal oedema, and then a blurring of vision, aggravated by the progression to ulcers in the corneal surface. The dry eye itself is termed xerophthalmia, whilst the changes to the eyeball is called keratoconjunctivitis sicca. The lacrimal glands may be enlarged.
The dry mouth is called xerostomia.This is characterised by difficulty in eating and especially swallowing dry food such as biscuits, without drinking water. The saliva provides a mechanism to maintain dental hygiene and lack results in caries, and oral infections including thrush and dental and salivary duct infection and salivary duct stones. The salivary glands including parotid and submandibular glands may enlarge.
Dryness can occur at other mucosal sites - including the trachea, bronchi and the genital tissue - especially vagina. Skin dryness can also be observed.
Systemic manifestations include stiffness, fatigue, malaise, low grade fevers,and generalized as well as local body pain. Pain may be arthralgia as well as myalgia, but a frank arthritis may occur. The arthritis tends to be non erosive, unless as part of a frank co-occurence with Rheumatoid arthritis.
Involvement of organs can occur - including:
Renal involvement is characterised by tubular acidosis, with secondary kidney stones and renal impairment. The direct inflammation of the filtering mechanism of the kidney - the glomerulus is occasionally involved.
The lungs are involved as a secondary problem from reduced airway protection, and bronchitis and pneumonia may occur, as well as a infiltration and fibrosis of the lung tissue - interstitial lung disease.
Blood vessel involvement includes, spasm with cold exposure - raynauds, and more rarely, inflamation of the wall of small and medium sized blood vessels, causing obstruction and reduction of blood supply, ischaemia, and may result in peripheral nerve dysfunction, and central brain disorder, including paralysis, dementia or meningitis / encephalitis.
Neurological problems, include cranial nerve lesions, ie trigeminal or ophthalmic nerve, and lesions of peripheral nerve - including neuropathy of sensory and motor nerves, and mononeuritis.
The thrust of investigations are to establish the presence of true dry eye or mouth, followed by demonstrating typical change on biopsy of affected tissue.
Evaluation of dry eye
Evaluation of dry mouth - A sialogram can be done to assess the ducts of the salivary glands.Flow in the ducts can be measured with a sialometer.
Biopsy of the lower lip is the usual site for a biopsy - done as a simple procedure with local anaesthetic. The histology shows nests or collections of lymphocytes and plasma cells - and a count is done of these to give an aggregate score for the specimen.
Blood tests may reveal antibodies - especially the Anti Ro (SSA) antibody. 40% of patients are positive and the Anti LA (SSB) antibody. 50% of patients are positive. Rheumatoid factor may be positive.
The main differentiation is primary Sjogren (where the condition occurs in isolation), versus secondary to other autoimmune disease, especially rheumatoid arthritis and lupus. The possibility of other conditions that affect the salivary glands - including sarcoidosis should also be considered.
Treatment is aimed at symptomatic, preventative and disease modifying roles. Symptomatic therapy includes use of substitutes for saliva or tears. The salivary substitutes are based on sugar free viscous substitutes.There are several such preparations available, and have variable benefit. The use of sugar or acidic containing salivary stimulants cause major dental decay, and should not be used.
Therapy is required for prevention of the complications of dry eye - with reduction in secondary conjunctivitis, infection, corneal ulceration and visual impairment.
Preventative dental hygiene is vital to prevent oral caries.
The use of steroid or immunosupressive therapy is largely reserved for patients with organ involvement such as kidney, lung, nerve or blood vessel disease
Patients may develop secondary lymphoma, and vigilance in this regard and appropriate chemotherapy is required.