Systemic Lupus Erythematous

Question 1

Definition

Answer 1

Chronic systemic autoimmune condition caused by a type 3 hypersensitivity reaction due to a complex interplay between genetic + environmental factors.
- Apoptotic debris = poorly cleared + activities an immune response generated antibody-antigen complexes which deposit in tissues and activate complement, causing tissue inflammation + damage.

Question 2

Epidemiology

Answer 2

Middle-aged: peak age of onset is between 15 and 45 years old
Female gender
African and Afro-Caribbean

Question 3

Risk factors

Answer 3

Family history
Drugs: procainamide, isoniazid, hydralazine = drug-induced Lupus
HLA associations: HLA-B8, -DR2, -DR3

Question 4

Aetiology

Answer 4

Environmental triggers
- UV light causes cell death = This creates apoptotic bodies. Specific genes = reduced clearance
- Smoking
- Medications
- Oestrogen
- EBV
Genetic associations:
- HLA-B8, -DR2, -DR3

Question 5

Pathophysiology

Answer 5

Impaired apoptotic debris presented to Th2 -> B cell activation -> antigen-antibody complexes
- Activation of these antibodies generates inflammatory response
This deposition can occur anywhere in the body so multiple organs are affected
e.g. skin, joints, kidneys, heart + brain

Question 6

General signs

Answer 6

Fatigue,
Fever,
Lymphadenopathy

Question 7

Dermatological Signs (MC)

Answer 7

MALAR BUTTERFLY RASH
PHOTOSENSITIVITY
Discoid rash: scaly, well-demarcated plaques in sun-exposed areas
Raynaud’s phenomenon

Question 8

Musculoskeletal Signs (MC)

Answer 8

Arthralgia
Non-erosive arthritis

Question 9

Pulmonary Signs

Answer 9

Pleurisy
Interstitial lung disease
Pulmonary embolism

Question 10

Cardiovascular Signs

Answer 10

Pericarditis and myocarditis: pericarditis is the most common cardiac manifestation
Libman-Sacks endocarditis (non-infective)
Neonatal heart block: anti-Ro antibodies cross the placenta

Question 11

Gastrointestinal Signs

Answer 11

Lupus peritonitis
Mesenteric artery occlusion

Question 12

Renal Signs

Answer 12

Lupus nephritis

Question 13

Neuropsychiatric Signs

Answer 13

PSYCHOSIS
SEIZURES
Depression and anxiety

Question 14

Ophthalmological Signs

Answer 14

Keratoconjunctivitis sicca
Sjögren’s syndrome

Question 15

Haematological Signs

Answer 15

Autoimmune haemolytic anaemia (warm)
Thrombocytopaenia
Leukopenia
Antiphospholipid syndrome

Question 16

Other Signs

Answer 16

MOUTH AND NOSE ULCERS

Question 17

Overlap condition

Answer 17

Scleroderma
Rheumatoid arthritis
Mixed connective tissue diseases (CTDs)
Raynaud’s syndrome
Sjögren’s syndrome

Question 18

Diagnosis

Answer 18

Bloods
- RAISED ESR BUT NORMAL CRP
- FBC = Anaemia
- U + E = Lupus Nephritis
Antibodies
- ANA = most sensitive
- Anti-dsDNA = highly specific but less sensitive = used to monitor progression
* BOTH COMBINED = DIAGNOSTIC *
- Anti-Smith, Anti-RO, Anti-La
Urine Dipstick
- Haematuria + Proteinuria

Question 19

Treatment

Answer 19

Lifestyle:
- Avoid sun + using sunscreen
- Cessation of triggering drugs
Management of Acute flare:
- Mild = Prednisolone + Hydrochloroquine + NSAIDS
- Moderate/Severe = Prednisolone + Hydroxychloroquine + Immunosuppressant (AZANTHIOPRINE OR CICLOSPORIN)
Maintenance:
Monotherapy of hydroxychloroquine

Question 20

Complications

Answer 20

CVD
Pericarditis
Interstitial lung disease -> Pulmonary Fibrosis
Recurrent miscarriages
Neuropsychiatric SLE