PowerPoint presentation on SLE by MMed Student, Moi University, Kenya

1. SYSTEMIC LUPUS ERYTHEMATOSUS
(SLE)
PRESENTER: DR. OWITI SYLAS
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2. OUTLINE
• Introduction
• Epidemiology
• Etiology
• Immunopathogenesis
• Clinical Features
• Complications
• Laboratory Diagnosis
• Immunotherapy
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3. INTRODUCTION
• Systemic lupus erythematosus is a chronic, multisystem,
inflammatory, autoimmune disorder characterized by formation of
autoantibodies directed against self-antigens and immune-complex
formation resulting in damage to essentially any organ.
• It is characterized by states of exacerbation and remission
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4. CONT..
• The immune system loses the ability to differentiate between foreign
cells and it’s own cells and tissues
• Antibodies against the immune system are formed
• The immune complexes that are formed build up in the tissue causing
inflammation, tissue damage, and pain.
• The most common type of auto-antibody that develops in people with
SLE is called an antinuclear antibody (ANA) because it reacts with
parts of the cell’s nucleus
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5. EPIDEMIOLOGY
• 80-90% of lupus patients are female (F:M 9:1)
• Age of onset
• Women: 15–44 years
• Men: no particular age
• 80% of lupus patients are between 15 and 45 years of age.
• Approximately 5% of cases present in childhood, mainly around
puberty (rare in children below 9 yrs)
• Lupus affects more African Americans, Asian Americans, Hispanics,
and Native Americans than Caucasians
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6. ETIOLOGY
• The specific cause is unknown, but several predisposing factors
have been identified:
1.Genetic factors: HLA-DR2 and HLA-DR3 are commonly present
in individuals with SLE.
Genetic deficiency of Classical pathway complement proteins (C1q,
C2, C4) in approx. 10% of affected individuals
2.Environmental agents:
• Cigarette smoking and silica exposure increase the risk of
developing SLE.
• UV light and EBV infection may trigger disease flares, but there is
insufficient evidence on whether they cause SLE.
• Drugs such as procainamide or hydralazine
• Dietary factors
3.Hormonal factors: Hyperestrogenic states (e.g., due to oral
contraceptive use, postmenopausal hormonal therapy, endometriosis)
are associated with an increased risk of SLE
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7. IMMUNOPATHOGENESIS
• The exact pathomechanism of SLE is not fully understood, but the
following two processes are the most widely accepted hypotheses:
Autoantibody development: deficiency of classical complement proteins
(C1q, C4, C2) → failure of macrophages to phagocytose immune
complexes and apoptotic cell material (i.e., plasma and nuclear antigens) →
dysregulated, intolerant lymphocytes targeting normally hidden intracellular
antigens → autoantibody production (e.g., ANA, anti-dsDNA)
Autoimmune reactions
• Type III hypersensitivity (most common in SLE) → antibody-antigen
complex formation in microvasculature → complement activation and
inflammation → damage to skin, kidneys, joints, small vessels
• Type II hypersensitivity → IgG and IgM antibodies directed against
antigens on cells (e.g., red blood cells) → cytopenia
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8. Immunopathogenesis
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9. Immunopatho
genesis
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10. Clinical Features
• SLE is a systemic disease characterized by phases of remission and
relapse.
• Some individuals only experience mild symptoms, while others
experience severe symptoms and rapid disease progression.
• SLE can affect any organ.
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11. Clinical
Features
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12. COMPLICATIONS
1. Infections
• Responsible for 25–50% of deaths in patients with SLE
• Bacterial: skin, lungs, and urinary tract
• Viral: VZV, CMV, and HPV
• Patients with SLE are at increased risk of developing infections
because of disease-related factors (e.g., pancytopenia) and/or
immunosuppressive treatment
2. Cardiovascular disease
• ↑ Risk of thrombosis in all patients with SLE (especially if secondary
antiphospholipid syndrome is present)
• ↑ Risk of MI and stroke because of accelerated atherosclerosis
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13. COMPLICATIONS
• Libman-Sacks endocarditis
• Pancytopenia
• Non-Hodgkin lymphoma
• Interstitial lung disease, pulmonary hypertension
• Medication-induced adverse effects
• Pregnancy-related adverse effects eg PET, Miscarriage, DVT
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14. DIAGNOSIS
• SLE is a clinical diagnosis.
• Consider a diagnosis of SLE in
patients with constitutional
symptoms and features
involving ≥ 2 organs or
systems.
• SLE classification requires
all of the following to be met:
• Entry criterion (ANA titer of ≥
1:80)
• At least one clinical criterion
• Total additive score ≥ 10
points (calculated by adding
the highest-weighted criteria
within each domain together)
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15. LABORATORY DIAGNOSIS
1. Antinuclear antibodies (ANAs)
• Positive titers of ≥ 1:80 have ∼ 98% sensitivity for SLE (entry criterion for the 2019
EULAR/ACR classification criteria for SLE).
• If negative, consider differential diagnoses and/or follow-up with the patient regularly.
2. Antigen-specific ANAs: Request only if ANAs are positive.
• Anti-dsDNA antibodies: Autoantibodies against double-stranded DNA
• Positive in 60–70% of patients
• Highly specific for SLE
• Levels correlate with disease activity (especially lupus nephritis activity).
• Anti-Sm antibodies
• Autoantibodies against Smith antigens (nonhistone nuclear proteins)
• Positive in < 30% of patients, but highly specific for SLE
• Antiphospholipid antibodies: Screen all patients for antiphospholipid syndrome
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16. 3. Laboratory markers of disease activity and/or organ damage in
SLE
• Complement levels:
• ↓ C3 and/or ↓ C4 in patients with active disease
• Inflammatory markers:
• ESR: may be elevated in patients with active disease
• CRP: often normal (may be elevated in patients with serositis, arthritis, or
infections)
• CBC: may show leukopenia, thrombocytopenia, and/or autoimmune hemolytic
anemia or anemia of chronic disease
• CMP: may show ↑ BUN and/or creatinine, and/or electrolyte abnormalities
• Urinalysis and urine microscopy: may show proteinuria, hematuria, and/or
urinary casts
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17. ADDITIONAL DIAGNOSTICS
Imaging studies
• Imaging studies can help in the assessment of organ or joint
involvement.
• X-ray joints: Perform in patients with articular symptoms.
• X-ray or CT chest: Perform in patients with symptoms of pulmonary
involvement (e.g., interstitial lung disease, pleuritis).
• Echocardiography: Consider in patients with suspected pericardial effusion
or Libman-Sacks endocarditis.
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18. Histopathology
• Skin biopsy
• Consider in patients with atypical dermatologic presentation or no response to
initial therapy.
• Lupus band test (LBT): a direct immunofluorescence staining technique used
to detect immunoglobulin and complement component deposits along the
dermoepidermal junction in affected and unaffected skin in patients with SLE.
• Kidney biopsy: in case of suspected lupus nephritis
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19. Immunotherapy
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