Connective tissue disorders Flashcards
What are the key factors in SLE aetiology? → Systemic Lupus Erythematosus
(1) Autoimmune, genetic predisposition (HLA genes)
(2) Hormonal (↑ oestrogen)
(3) Environmental
(UV light, infections, medications)
Who is most at risk for SLE?
(1) Women aged 20-40
(2) Especially of Afro-Caribbean, Hispanic, Asian, or Chinese descent
(3) Smokers
What is the key immune mechanism in SLE pathophysiology?
The immune system attacks cells, forming immune complexes (Type III hypersensitivity) causing inflammation and tissue damage
What are the three levels of SLE severity?
Mild (cutaneous)
Moderate (arthritis, effusions) Severe (organ-threatening disease)
What are some non-specific symptoms of SLE?
Fever, fatigue, weight loss
What is a key cutaneous feature of SLE?
Photosensitive malar rash, usually on the face
What is the difference between SLE arthritis and RA?
SLE arthritis is non-erosive, with no damage to joints. Deformities are reversible
What are common haematological findings in SLE?
(1) Leukopenia
(2) Thrombocytopenia
(3) Haemolytic anaemia
(4) Lymphadenopathy
What is required to diagnose SLE according to the EULAR/ACR criteria?
(1) ≥11 criteria
(2) With at least 1 clinical and 1 lab finding, or biopsy-proven lupus nephritis
(3) with positive ANA or anti-dsDNA
What is the significance of ANA in SLE diagnosis?
High sensitivity; a negative ANA test makes SLE unlikely
Which autoantibody is most specific for SLE?
Anti-Smith (Anti-Sm)
What does a positive urine dipstick indicate in suspected SLE patients?
Proteinuria >0.5g/24 hours suggests lupus nephritis; biopsy confirms
What is the 1st line treatment for mild-moderate SLE? (technically 2nd)
Hydroxychloroquine + NSAIDs
= for short-term symptom control
What is the first-line treatment of SLE?
- Sun management
- Minimize steroid use
What do you stop if the patient has lupus nephritis?
NSAID
What is the 3rd line treatment for moderate-severe SLE?
(1) Hydroxychloroquine
(2) Acute flareups: azathioprine (immunosuppressant) + oral steroids (short periods)
What is the 4th line treatment for severe SLE?
Hydroxychloroquine + prednisolone + warfarin + mycophenolate mofetil
Example of severe SLE
lupus nephritis or CNS lupus
What complication is associated with steroid use in SLE?
Avascular necrosis, especially of the femoral head
What are key factors monitored in SLE management?
Anti-dsDNA,
Complement levels
Urinalysis
What heart-related complication can occur in babies born to SLE mothers?
Congenital heart block
What is the basic definition of Sjögren’s syndrome?
An autoimmune condition that destroys exocrine glands, causing dryness
What is the primary demographic affected by Sjögren’s syndrome?
Middle-aged females (9:1 ratio)
What glands are primarily affected in Sjögren’s syndrome?
Lacrimal (tear) and salivary glands
What are the main symptoms of Sjögren’s syndrome?
(1) Dry eyes
(2) Dry mouth
(3) Dry throat
(4) Vaginal dryness
(5) Joint pain
(6) Fatigue
What is a key eye symptom of Sjögren’s syndrome?
Gritty feeling in the eyes
What is the most specific antibody for diagnosing Sjögren’s syndrome?
Anti-Ro and Anti-La antibodies
What are common blood markers seen in Sjögren’s syndrome?
- Positive ANA, anti-Ro, anti-La, 2. 2. Raised IgG
- High ESR/plasma viscosity
What test may be done if antibodies are negative in suspected Sjögren’s syndrome?
Salivary gland ultrasound and biopsy
What medication can help with Sjögren’s syndrome sicca (dryness) symptoms?
Pilocarpine
Which drug can sometimes help with arthralgia and fatigue in Sjögren’s syndrome?
Hydroxychloroquine
What type of arthritis is associated with Sjögren’s syndrome as a complication?
Psoriatic arthritis
What is the primary management strategy for Sjögren’s syndrome?
Symptom control with tear and salivary replacements
What is systemic sclerosis?
Autoimmune inflammation and skin thickening (Scleroderma) due to increased collagen deposition
What are the peak incidence years for Scleroderma?
30-50 years
What are the two types of systemic sclerosis?
Limited systemic sclerosis (lSSc) and diffuse systemic sclerosis (dSSc)
What is the triad of symptoms in Scleroderma?
(1) Vascular changes
(2) Fibrosis
(3) Activation of the immune system
What is the primary manifestation of limited systemic sclerosis (lSSc)?
Skin involvement is usually confined to the face, hands, forearms, and feet
What is the association of antibodies with limited systemic sclerosis?
Anti-centromere antibody (ACA)
What is the association of antibodies with diffuse systemic sclerosis?
Anti-SCL-50 antibody and anti-RNA polymerase III association
Describe the difference between dSCC with ISCC
(1) Skin changes develop more rapidly
(2) Can involve the trunk
(3) Early significant organ involvement
(4) The Raynaud phenomenon often coincides with or follows the onset of other symptoms whereas in ISCC, the Raynaud phenomenon precedes the onset of other symptoms.
What is the difference between ISCC and dSCC?
Diffuse - above and below elbows and knees + face and trunk
Limited - only below elbows and knees + face
Symptoms of systemic sclerosis
(1) Thickening and hardening of the skin
(2) Sclerodactyly - thickening of the skin of the fingers and hands which can cause loss of dexterity of hands