4. Systemic lupus erythematosus - definition, prevalence, etiology, pathogenesis, clinical presentation/clinical forms, disease course, diagnosis, differential diagnosis, management. Secondary antiphospholipid syndrome – diagnosis, active and supportive treatment.

Definition

Multisystem autoimmune disorder characterised by the production of autoantibodies against nuclear antigens and factors of the coagulation system.

• Immune system attacks its own tissues, causing widespread inflammation and tissue damage in the affected organs.
• It can affect the joints, skin, brain, lungs, kidneys, and blood vessels.

Etiology

More common in women 15 – 64 due to hormonal differences, this is not the same for other age groups

• Idiopathic
• Genetic
• Exacerbated by sunlight and drugs
• Sunlight causes skin lesions and immunological and visceral activation
• Exogenous oestrogen intake in childbearing aged women

Pathogenesis and Pathanatomy

Defects in clearance of apoptotic bodies

• Dysregulated innate and adaptive immune response
• Loss of self-tolerance with activation of autoreactive T and B cells leading to production of pathogenic autoantibodies and tissue injury

↓ levels of CRP and ↑ in auto antibodies

Clinical Features

4.1 Anamnesis

Vary from person to person, depending the organs affected. And the symptoms may come and go.

1. Low Fever
2. Hairloss
3. Lymphadenopathy
4. Raynaud’s phenomenon- ↓ blood flow to the fingers.
5. Arthalgia & Joint Edema

4.2 Physical Examination

• Inspection - Edema – Renal system is involved- ↓ diuretics and hypertension

• Headache & Seizures
• Swan neck deformities →
• Muskuloskeletal involvement - Arthalgia
• Dematological examinationl - Cutaneous lesions, butterfly rash, maculopapular rash
• Discoid lupus- coin shape rash
• Heart involvement – Can affect all 3 layers of heart →
• Lung involvement – Interstitial fibrosis,
• pulmonary vasculitis,
• interstitial pneumonitis

Pericardium

• Pericarditis with pericardial rub
• Pleural effusion with chest pain and dyspnea

Myocardium

• Fibrinoid degeneration, MI

Endocardium

• Libman-Sacks endocarditis found at autopsy
• GIT involvement – Hepatomegaly, abdominal pain, ascites,
• dysphagia, pancreatitis Liver function test abnormalities
• CNS involvement – Seizures, cerebrovascular disease,
• aseptic meningitis, headache
• PNS involvement –Cranial neuropathy, Gillian-barre syndrom - myasthenia gravis