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Sjogren's Syndrome Affecting mostly women, Sjogren’s syndrome is an autoimmune disorder in which the body’s immune system mistakenly attacks its own moisture-producing glands. The hallmark symptoms of Sjogren’s syndrome are dry mouth and dry eyes. When Sjogren’s syndrome is accompanied by a connective-tissue disease, such as
rheumatoid arthritis
Differential diagnosis Immunological blood serum tests for ANA ( Anti-
Nuclear Antibody ) Anti-Ro (SSA) RF ( Rheumatoid
factor) AQUEOUS
DEFICIENCY
Sjogren's - autoimmune destruction of lacrimal gland ducts - reflex secretions down and dry mouth also.
Schirmer 5
minute test Tear meniscus
height May co-exist with evaporative dry eye
EVAPORATIVE
Meibomian orifices obstructed with desquamed epithelial cells that have become keratinised. Lipids thicken, sebaceous secretions stagnate and exotoxic free fatty acids are released to destabilise the oil layer.
Long-term therapy with Isotretinoin ( Roaccutane®) for acne can cause meibomian gland atrophy with associated reduced lipids.
[The terminology of the two types
of hordeolum have become confusing. Meibomian glands run vertically, within the
tarsal plate, open at tiny puncta along the lid margin, and secrete oil to coat
the tear film. The glands of Zeiss and Moll are the sebaceous glands opening
into the follicles of the eyelashes. Both can become occluded and superinfected,
producing meibomianitis (internal hordeolum) or a sty (external hordeolum). A
chronic granuloma of the meibomian gland is called a chalazion, will not drain,
and requires excision]
[One of the most devastating ocular complications of systemic drugs is Stevens-Johnson Syndrome. At least 200 drugs have been implicated in this acute hypersensitivity reaction affecting the mucous membranes of mainly young adults. Goblet cell loss and occluded lacrimal gland ducts ] TREATMENT INFO
Reflex tear secretion is by parasympathetic fibres of the 7th facial nerve in response to afferent trigeminal 5 nerve stimulation. (eyes are drier at night - pilocarlpine a parasymathomimetic is a treatment) Basal tear production is predominantly under sympathetic control by regulating the blood flow via the smooth muscle surrounding the arterioles of the lacrimal gland. Aqueous is also secreted from the accessory glands of Krause and Wolfring situated in the upper conjunctival fornix and tarsal conjunctica respectively.
PROXYMETACAINE
0.5% (kept in fridge)
UPPER PUNCTA : oph
division of trigeminal V nerve
SODIUM HYALURONATE
THERATEARS Hypotonic, newtonian fluid - has no biphasic viscoelastcity. Active ingredient is 0.25% sodium carboxymethyl cellulose with a patented mixture of electrolites. Restarts conjunctival goblet cells secretions for mucous production and immunogobulins (Ig)
All five Ig's found in higher concentrations in basal tear layers, less in reflex tears, and IgA concentration increases during sleeps when lacrimal gland activity decreases. Igs are therefore continually secreted by conjunctiva. IgA - dominant in mucous membranes prevents microbial attachment to epithelial cells WITH ANTIGEN CHALLENGE IgD - helps B-cells to differentiate. IgM - marks bacteria for destruction by changing compliment C3 to C3b for opsinisation. IgG - go (activate) macrophages to kill +/- IgE - in small amounts unless acute allergy with conjunctival chemosis. Then IGE + mast cells = histamine. [Differentiate, Mark and Go !] CYCLOSPORIN A ( not in the UK )
Works by preventing pro-inflammatory cytokines from T-lymphacytes Many controlled studies have shown reduced corneal staining, better tear
volumes,
Dry eye, regardless of whether it is associated with a systemic autoimmune disorder, is a lymphocyte-mediated inflammatory disease.
Allergan's Restasis™ cyclosporine ophthalmic emulsion, 0.05% is in Phase III clinical trials.
Doxycycline It modifies meibomian gland secretions by killing the bacteria that split neutral meimbomian gland oils into irritating fatty acids. Contraindicated in hepatic disorders and not for systemic lupus. Warnings- decrease alcohol consumption and protect strong UV light Side effects possible similar to other tetracycline antibiotics, nausea, vomiting, diarrhoea, colitis, headache
Treatment with SalagenSalagen tablets (pilocarpine) have been marketed in the United States as a treatment for symptoms of Sjögren’s syndrome. The 5-mg tablets stimulate the exocrine glands to increase their moisture-producing activity. The maximum dosage of Salagen is four times a day. Dr. Onofrey explained that some patients have difficulty tolerating Salagen. “Salagen is a parasympathomimetic drug, and it stimulates exocrine function,” he said. “So patients will report increased tears and saliva, which is good, but they might also complain of increased sweating and bronchial secretions.” For this reason, Dr. Onofrey said, he would not prescribe Salagen for an asthmatic, whose condition could be worsened by the drug. Salagen would also be contraindicated for those with any sort of gastrointestinal problems. “Parasympathomimetic drugs stimulate the gastrointestinal tract, so they can cause diarrhea and cramping,” he said. “It should not be used in people with gastric reflux disease, ulcers or irritable bowel syndrome. It is contraindicated for anyone with gastrointestinal problems, particularly if he or she is taking an anticholinergic drug.” Dr. Onofrey said he titrates the drug, starting at a dosage of one pill twice a day, working up to the maximum dosage of four times a day.
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