Systemic Lupus Erythematosus Flashcards
1
Q
What does SLE stand for?
A
Systemic lupus erythematosus
2
Q
Why is SLE considered a “systemic” disorder?
A
Because it affects multiple organs and systems in the body.
3
Q
What does “erythematosus” refer to in SLE?
A
It refers to the typical red malar rash across the face.
4
Q
Who is more commonly affected by SLE?
A
- Women<br></br>- Individuals of Asian, African, Caribbean, and Hispanic ethnicity<br></br>- Young to middle-aged adults
5
Q
Describe the course of SLE.
A
SLE typically takes a relapsing-remitting course, with flares of worse symptoms and periods where symptoms settle.
6
Q
What are significant complications of SLE?
A
Cardiovascular disease and infection are significant complications.
7
Q
What characterizes the pathophysiology of SLE?
A
SLE is characterized by anti-nuclear antibodies (ANA), which are autoantibodies against proteins within the cell nucleus. These antibodies generate a chronic inflammatory response, leading to the condition’s features.
8
Q
What are some non-specific symptoms of SLE?
A
- Fatigue<br></br>- Weight loss<br></br>- Arthralgia (joint pain)<br></br>- Non-erosive arthritis<br></br>- Myalgia (muscle pain)<br></br>- Fever<br></br>- Photosensitive malar rash<br></br>- Lymphadenopathy<br></br>- Splenomegaly<br></br>- Shortness of breath<br></br>- Pleuritic chest pain<br></br>- Mouth ulcers<br></br>- Hair loss<br></br>- Raynaud’s phenomenon<br></br>- Oedema (due to nephritis)
9
Q
What is the characteristic appearance of the malar rash in SLE?
A
The malar rash is “butterfly” shaped across the nose and cheeks, triggered or worsened by sunlight.
10
Q
What are some abnormal findings in investigations for SLE?
A
- Autoantibodies<br></br>- Full blood count may show anemia of chronic disease, low white cell count, and low platelets<br></br>- Elevated CRP and ESR with active inflammation<br></br>- Decreased C3 and C4 levels in active disease<br></br>- Urinalysis and urine protein:creatinine ratio showing proteinuria in lupus nephritis<br></br>- Renal biopsy used to investigate lupus nephritis
11
Q
What is the significance of anti-nuclear antibodies (ANA) in SLE diagnosis?
A
Around 85% of patients with SLE will be positive for ANA (SENSTIVE) . A positive result needs to be interpreted in the context of their symptoms, as it can also be positive in healthy individuals and those with other autoimmune conditions(NOT SPECIFIC).
12
Q
What is the specificity of anti-double stranded DNA (anti-dsDNA) antibodies in SLE?
A
Anti-dsDNA antibodies are highly specific to SLE. A positive result suggests SLE rather than other causes. Approximately half of patients with SLE have anti-dsDNA antibodies, and their levels vary with disease activity, making them useful in monitoring disease activity and treatment response.
13
Q
What does an extractable nuclear antigen panel look for, and how does it aid in the diagnosis of connective tissue disorders?
A
The panel looks for antibodies to specific proteins in the cell nucleus. It helps diagnose and distinguish between specific connective tissue disorders. Examples include:<br></br>- Anti-Sm (highly specific to SLE but not very sensitive)<br></br>- Anti-centromere antibodies (associated with limited cutaneous systemic sclerosis)<br></br>- Anti-Ro and anti-La (associated with Sjögren’s syndrome)<br></br>- Anti-Scl-70 (associated with systemic sclerosis)<br></br>- Anti-Jo-1 (associated with dermatomyositis)
14
Q
What complications can arise from antiphospholipid antibodies in SLE, and what is their association with venous thromboembolism?
A
Antiphospholipid antibodies can lead to antiphospholipid syndrome in up to 40% of SLE patients, increasing the risk of venous thromboembolism.
15
Q
What criteria are used for the diagnosis of SLE, and what organizations developed them?
A
The European League Against Rheumatism (EULAR) / American College of Rheumatology (ACR) criteria (2019) can be used for diagnosis. These criteria consider clinical features and autoantibodies suggestive of SLE.
16
Q
What are the leading causes of death in SLE, and how does chronic inflammation contribute to cardiovascular disease?
A
Cardiovascular disease is a leading cause of death in SLE. Chronic inflammation in blood vessels leads to hypertension and coronary artery disease.
17
Q
What are some complications of SLE related to the hematologic system?
A
- Anemia of chronic disease<br></br>- Autoimmune hemolytic anemia<br></br>- Bone marrow suppression by medications<br></br>- Kidney disease contributing to anemia, leucopenia (low white cells), neutropenia (low neutrophils), and thrombocytopenia (low platelets)
18
Q
What are the manifestations of pericarditis and pleuritis in SLE?
A
- Pericarditis causes sharp chest pain that worsens on lying flat.<br></br>- Pleuritis causes sharp chest pain on inspiration.
19
Q
How does lupus nephritis contribute to end-stage renal failure in SLE, and what investigations are involved in its assessment?
A
Lupus nephritis (inflammation in the kidney) can becauses by diffuce proliferative glomerulonephritis. Investigations include a urine protein:creatinine ratio and renal biopsy. The renal biopsy is often repeated to assess the response to treatment.
20
Q
What is neuropsychiatric SLE, and what are some manifestations of it?
A
Neuropsychiatric SLE is caused by inflammation in the central nervous system. It can present with optic neuritis (inflammation of the optic nerve), transverse myelitis (inflammation of the spinal cord), or psychosis.
21
Q
What are the reproductive complications associated with SLE?
A
Recurrent miscarriage is more common in SLE. There is also an increased risk of intrauterine growth restriction, pre-eclampsia, and pre-term labor.
22
Q
How is venous thromboembolism associated with antiphospholipid syndrome in SLE?
A
Antiphospholipid syndrome occurring secondary to SLE is associated with an increased risk of venous thromboembolism.
23
Q
What are essential measures in managing the photosensitive malar rash in SLE?
A
Suncream and sun avoidance are essential measures.
24
Q
Name the first-line treatment options for SLE.
A
- Hydroxychloroquine<br></br>- NSAIDs (Nonsteroidal Anti-Inflammatory Drugs)<br></br>- Steroids (e.g., prednisolone)
25
What are the treatment options for resistant or more severe SLE?
- DMARDs (Disease-Modifying Antirheumatic Drugs) such as methotrexate, mycophenolate mofetil, or cyclophosphamide
- Biologic therapies
- Biologic therapies
26
Which biological therapy targets the CD20 protein on B cells?
Rituximab
27
What is the target of Belimumab, a monoclonal antibody used in SLE treatment?
Belimumab targets B-cell activating factor.
28
How does Rituximab work in treating SLE?
Rituximab is a monoclonal antibody that targets the CD20 protein on the surface of B cells.
29
What is the role of Hydroxychloroquine in SLE treatment?
Hydroxychloroquine is a first-line treatment option that aims to control symptoms and reduce complications.
30
Besides their anti-inflammatory effects, what additional property makes NSAIDs useful in SLE?
NSAIDs (Nonsteroidal Anti-Inflammatory Drugs) are used for their anti-inflammatory effects and can help alleviate joint pain and other symptoms in SLE.
31
In more severe cases, what class of drugs, abbreviated as DMARDs, might be used in SLE treatment?
DMARDs (Disease-Modifying Antirheumatic Drugs) such as methotrexate, mycophenolate mofetil, or cyclophosphamide may be used in more severe or resistant cases of SLE.
32
What is the significance of Biologic therapies in SLE management?
Biologic therapies, including Rituximab and Belimumab, offer treatment options for resistant or severe cases of SLE. They target specific pathways involved in the disease process.
33
What is the role of Steroids in SLE treatment?
Steroids, such as prednisolone, are first-line treatment options that help control inflammation and manage symptoms in SLE.
34
Why is sun avoidance important in managing the photosensitive malar rash in SLE?
Sun avoidance is crucial in managing the photosensitive malar rash as sunlight can trigger or worsen the rash. Suncream is also recommended to protect the skin from harmful UV rays.
35
What does SLE stand for?
Systemic Lupus Erythematosus
36
What are the main organs and systems involved in SLE?
The skin, joints, kidneys, blood cells, and nervous system are the main organs and systems involved in SLE.
37
What are the autoimmune factors contributing to SLE?
- Genetic predisposition, particularly HLA genes
- Hormonal factors, with an increase in estrogen
- Environmental factors, including UV light, bacterial/viral infections, and certain medications
- Hormonal factors, with an increase in estrogen
- Environmental factors, including UV light, bacterial/viral infections, and certain medications
38
What is the ratio of prevalence between women and men in SLE?
SLE is more prevalent in women, with a ratio of 9:1.
39
At what age range does SLE usually present?
SLE usually presents in the childbearing years, typically between the ages of 20 and 40.
40
Which ethnic groups are more prone to SLE?
SLE is more common and more severe in individuals of Afro-Caribbean, Hispanic American, Asian, and Chinese ethnicity.
41
Describe the pathophysiology of SLE.
- Loss of immune regulation leads to increased and defective apoptosis
- Necrotic cells release nuclear materials, acting as auto-antigens
- Autoimmunity develops from exposure to nuclear and cellular auto-antigens
- B and T cells are stimulated, leading to the production of autoantibodies
- Immune complexes (type III hypersensitivity) form from auto-antigens and autoantibodies
- Complement activation attracts leukocytes and releases cytokines, perpetuating inflammation
- Necrotic cells release nuclear materials, acting as auto-antigens
- Autoimmunity develops from exposure to nuclear and cellular auto-antigens
- B and T cells are stimulated, leading to the production of autoantibodies
- Immune complexes (type III hypersensitivity) form from auto-antigens and autoantibodies
- Complement activation attracts leukocytes and releases cytokines, perpetuating inflammation
42
What is Lupus nephritis, and what percentage of lupus patients experience renal involvement?
Lupus nephritis is the involvement of the kidneys in lupus. Up to 50% of lupus patients will have renal involvement at presentation, and up to 60% during the course of their disease. The most frequently observed abnormality is proteinuria.
43
How is renal disease in lupus differentiated?
Renal disease in lupus is differentiated by renal biopsy using the ISN classification I-VI.
44
What is the image provided, and how does it relate to SLE?
The image illustrates the pathophysiology of SLE, showing the steps from immune dysregulation to inflammation and tissue damage.
45
What are the classical presentations of SLE?
The classical presentation of SLE typically includes systemic upset (fever, myalgia, fatigue, and weight loss) along with joint and/or skin involvement.
46
What are the subtypes of SLE, and how do they differ?
- SLE: Involves multiple organ systems.
- Subacute cutaneous lupus (SCLE): Presents with small erythematous lesions on the neck, shoulders, and forearms, sparing the face. Represents 10% of SLE cases.
- Discoid lupus erythematosus (DLE): A non-cancerous chronic skin condition with erythematous raised scaling plaques, triggered by UV light exposure. Affects the face, neck, and head and is associated with a 10-15% risk of developing SLE.
- Drug-induced lupus: Involves systemic manifestations, usually sparing the renal and neurological systems.
- Subacute cutaneous lupus (SCLE): Presents with small erythematous lesions on the neck, shoulders, and forearms, sparing the face. Represents 10% of SLE cases.
- Discoid lupus erythematosus (DLE): A non-cancerous chronic skin condition with erythematous raised scaling plaques, triggered by UV light exposure. Affects the face, neck, and head and is associated with a 10-15% risk of developing SLE.
- Drug-induced lupus: Involves systemic manifestations, usually sparing the renal and neurological systems.
47
What is the most common dermatological feature of SLE?
Photosensitivity, often in the form of a malar rash (symmetrical, butterfly-shaped rash across both cheeks).
48
What are some dermatological features of SLE?
- Recurrent mouth ulcers (common, occurring in 50% of cases)
- Raynaud's phenomenon (occurs in about 25% of cases)
- Non-scarring alopecia
- Cutaneous vasculitis, manifesting as splinter hemorrhages/purpura
- Raynaud's phenomenon (occurs in about 25% of cases)
- Non-scarring alopecia
- Cutaneous vasculitis, manifesting as splinter hemorrhages/purpura
49
What musculoskeletal symptoms can occur in SLE?
- Arthritis (nonerosive) or arthralgia
- Flitting arthralgia of at least 2 joints with early morning stiffness > 30 mins (rarely develops erosions, reducible deformities)
- Myalgia
- Jaccoud's arthropathy (in a minority of patients, tendon involvement can result in a nonerosive deformity similar to rheumatoid arthritis)
- Flitting arthralgia of at least 2 joints with early morning stiffness > 30 mins (rarely develops erosions, reducible deformities)
- Myalgia
- Jaccoud's arthropathy (in a minority of patients, tendon involvement can result in a nonerosive deformity similar to rheumatoid arthritis)
50
What are the systemic involvements of SLE?
- Renal: Lupus nephritis (most common cause of death in SLE patients)
- Cardiovascular: Pericarditis, myocarditis, increased cardiovascular risk, Libman-Sacks endocarditis (very rare)
- Respiratory: Pleurisy, pleural effusions, increased risk of pulmonary embolism in patients with antiphospholipid antibodies
- Neurological: Seizures, psychiatric changes (delirium, psychosis), headache, cranial nerve disorders
- Haematological: Leukopenia, thrombocytopenia, hemolytic anemia, lymphadenopathy
- Cardiovascular: Pericarditis, myocarditis, increased cardiovascular risk, Libman-Sacks endocarditis (very rare)
- Respiratory: Pleurisy, pleural effusions, increased risk of pulmonary embolism in patients with antiphospholipid antibodies
- Neurological: Seizures, psychiatric changes (delirium, psychosis), headache, cranial nerve disorders
- Haematological: Leukopenia, thrombocytopenia, hemolytic anemia, lymphadenopathy
51
What conditions can overlap with SLE in patients?
SLE patients can frequently develop conditions such as secondary Sjögren syndrome, secondary antiphospholipid syndrome, and mixed connective tissue disease.
52
How is the diagnosis of SLE confirmed?
The diagnosis is confirmed if there are ≥4 criteria (including at least 1 clinical and 1 lab criterion) or if there is biopsy-proven lupus nephritis with positive ANA or anti-DNA.
53
What is the significance of ANA (Anti-Nuclear Antibody) titer in SLE diagnosis?
- Present in almost all SLE patients.
- SLE is unlikely if the ANA test is negative.
- Can also be present in other diseases, such as other connective tissue diseases, thyroid disease, and liver disease.
- Present in lower titers in up to 20% of the healthy population.
- SLE is unlikely if the ANA test is negative.
- Can also be present in other diseases, such as other connective tissue diseases, thyroid disease, and liver disease.
- Present in lower titers in up to 20% of the healthy population.
54
If ANA titer is elevated, what tests are conducted for more specific SLE diagnosis?
- Anti-dsDNA: Present in 60% of lupus patients, highly specific, correlates with disease activity, associated with lupus nephritis.
- Antiphospholipid antibodies (APLS): Lupus anticoagulant, anti-cardiolipin antibodies, anti-beta-2 glycoprotein 1 antibodies. Associated with venous and arterial thrombosis, recurrent miscarriage, and livedo reticularis (net-like skin discoloration).
- Anti-Ro: Associated with neonatal lupus and congenital heart risk for the baby.
- Anti-Smith: Highly specific for lupus but only positive in ~30% of patients.
- Antiphospholipid antibodies (APLS): Lupus anticoagulant, anti-cardiolipin antibodies, anti-beta-2 glycoprotein 1 antibodies. Associated with venous and arterial thrombosis, recurrent miscarriage, and livedo reticularis (net-like skin discoloration).
- Anti-Ro: Associated with neonatal lupus and congenital heart risk for the baby.
- Anti-Smith: Highly specific for lupus but only positive in ~30% of patients.
55
What blood tests are conducted in SLE investigations?
- FBC and clotting screen: Prolonged PTT suggests lupus anticoagulant, check for antiphospholipid antibodies. SLE patients may have anemia of chronic disease, hemolytic anemia, thrombocytopenia, and leukopenia.
- U+Es: To screen for renal involvement.
- Complement levels (low C3 and C4): Low complement levels suggest active disease, particularly associated with renal and hematological disease.
- ESR and CRP: Suggestive of active disease in the absence of infection.
- U+Es: To screen for renal involvement.
- Complement levels (low C3 and C4): Low complement levels suggest active disease, particularly associated with renal and hematological disease.
- ESR and CRP: Suggestive of active disease in the absence of infection.
56
What does a positive urine dipstick test indicate in SLE?
Proteinuria >0.5g in 24 hours indicates lupus nephritis. Blood may also be present, along with red cell casts. A positive urine dipstick should prompt a renal biopsy to confirm nephritis.
57
How are imaging studies utilized in SLE investigations?
Imaging studies may be used to look for organ involvement, such as chest imaging for interstitial lung disease or MRI of the brain for cerebral vasculitis.
58
What non-immunomodulatory measures are recommended for SLE management?
- Photoprotection with sunscreen and prevention of overexposure to sunlight
- Avoidance of triggers (e.g., estrogen-containing contraception, sunlight, infections, stress)
- Optimization of cardiovascular health through strict BP and lipid control, and smoking cessation
- Improvement of bone health with calcium and vitamin D replacement, considering bisphosphonates in long-term glucocorticoid users
- Minimizing steroid use
- Monitoring disease activity using SLEDAI score
- Avoidance of triggers (e.g., estrogen-containing contraception, sunlight, infections, stress)
- Optimization of cardiovascular health through strict BP and lipid control, and smoking cessation
- Improvement of bone health with calcium and vitamin D replacement, considering bisphosphonates in long-term glucocorticoid users
- Minimizing steroid use
- Monitoring disease activity using SLEDAI score
59
What are the immunomodulatory treatments for mild-moderate SLE?
- Hydroxychloroquine
- Short course of NSAIDs for symptomatic control
- Steroids (Intra-articular for arthritis, topical for cutaneous manifestations; topical steroids may be sufficient for skin-only disease)
- Short course of NSAIDs for symptomatic control
- Steroids (Intra-articular for arthritis, topical for cutaneous manifestations; topical steroids may be sufficient for skin-only disease)
60
What are the recommended treatments for moderate-severe SLE involving inflammatory arthritis or organ involvement?
- Hydroxychloroquine (continued use for its disease-modifying effects)
- Immunosuppressants (e.g., azathioprine) or oral steroids for acute flare-ups to induce remission
- Treating organ complications appropriately
- Immunosuppressants (e.g., azathioprine) or oral steroids for acute flare-ups to induce remission
- Treating organ complications appropriately
61
How is severe organ disease in SLE, such as lupus nephritis or CNS lupus, typically treated?
-
62
In cases of unresponsive SLE, what alternative therapies may be considered?
- Other therapies such as IV immunoglobulin and rituximab may be necessary
63
What aspects should be regularly monitored in SLE patients?
- Anti-dsDNA antibodies and complement levels should be checked regularly
- Urinalysis for blood or protein
- Blood pressure and cholesterol due to increased cardiovascular disease risk
- Urinalysis for blood or protein
- Blood pressure and cholesterol due to increased cardiovascular disease risk
64
What complication is associated with an increased prevalence in SLE, especially related to steroid use?
- Avascular necrosis, usually of the femoral head, may be more prevalent and is often linked to steroid use
65
What are some common symptoms presented by Mary, a 42-year-old female with SLE?
Mary presents with multiple skin lesions on the arms, chest, and back, with a history of similar lesions in the past. She reports morning stiffness involving her fingers and knees and a history of multiple miscarriages. Blood tests revealed pancytopenia, very high ESR and CRP, and positive ANA and antiphospholipid antibodies.
66
What symptoms and findings are presented by Kyle, a 25-year-old man with SLE?
Kyle presents with flank pain, hematuria, migratory arthralgias, and photosensitivity. His blood tests show positive ANA and double-stranded DNA antibodies, low complement levels, very high ESR and CRP, and high creatinine. A urinalysis reveals proteinuria and red blood cell casts.
67
What is the underlying cause of SLE?
SLE develops when the person’s immune system recognizes nuclear antigens of the body’s own cells as foreign and attacks them. B cells start producing antibodies that bind to nuclear antigens, forming antigen-antibody complexes. These complexes deposit in various organs and tissues, leading to inflammation and damage. This process is a type III hypersensitivity reaction. Individuals lacking early complement proteins (C1q, C2, C4) are more prone to lupus. Many patients also develop antibodies targeting other cells, leading to pancytopenia (type II hypersensitivity reaction).
68
What are the key symptoms and findings associated with SLE?
The key symptoms and findings associated with SLE can be divided into four groups: 1. Skin Involvement: Malar rash (butterfly rash), discoid rash (chronic erythematous rash in sun-exposed areas), photosensitivity. 2. Musculoskeletal Symptoms: Morning stiffness, migratory arthralgias. 3. Hematological Abnormalities: Pancytopenia. 4. Immunological Findings: Positive ANA, positive antiphospholipid antibodies, low complement levels, very high ESR and CRP.
69
What are the symptoms associated with the mucosal membranes in SLE?
Lupus can cause ulcers in the mouth or nose due to damage to the inner membrane or mucosa of various tissues. Additionally, serositis, inflammation of the serosa (outer membrane of an organ or tissue), can manifest as pleuritis (inflammation of the lining around the lungs and chest cavity), peritonitis (inflammation of the lining of the abdomen), or pericarditis (inflammation of the lining of the heart). It can also lead to myocarditis or Libman-Sacks endocarditis.
70
What extraglandular manifestations are associated with SLE?
- **Arthritis**: Inflammation of two or more joints.
- **Kidney Damage**: Indicated by protein or cells in the urine, often caused by **diffuse proliferative glomerulonephritis**, the most common and severe type of glomerulonephritis in lupus. It can lead to end-stage kidney failure.
- **Neuropsychiatric** Conditions: Headaches, seizures, psychosis, mood disorders like depression.
- **Kidney Damage**: Indicated by protein or cells in the urine, often caused by **diffuse proliferative glomerulonephritis**, the most common and severe type of glomerulonephritis in lupus. It can lead to end-stage kidney failure.
- **Neuropsychiatric** Conditions: Headaches, seizures, psychosis, mood disorders like depression.
71
What is the most common and severe type of glomerulonephritis associated with lupus?
The most common and severe type of glomerulonephritis associated with lupus is diffuse**proliferative glomerulonephritis**, characterized by immune complex deposition along the glomerular basement membrane. Light microscopy may show diffuse thickening of the glomerular capillary walls with characteristic "**wire-loop" structures**. Lupus nephritis can ultimately lead to end-stage kidney failure.
72
What are the leading causes of morbidity and mortality among individuals with lupus?
The leading causes of morbidity and mortality among individuals with lupus are **end-stage kidney failure**, followed by infections and cardiovascular disease.
73
What are the lab findings related to blood in SLE?
- **Autoantibodies against Blood Components**: Leading to conditions like anemia, thrombocytopenia, or leukopenia.
- **Positive Serology for Antinuclear Antibodies (ANA)**: ANA targets nuclear antigens and is found in a large proportion of patients with lupus. While sensitive, it isn't very specific and can be found in other autoimmune diseases.
- **Positive Serology for Antinuclear Antibodies (ANA)**: ANA targets nuclear antigens and is found in a large proportion of patients with lupus. While sensitive, it isn't very specific and can be found in other autoimmune diseases.
74
What are the relatively specific antibodies for lupus, targeting small ribonucleoproteins and double-stranded DNA?
- **Anti-Smith**: An antibody against small ribonucleoproteins.
- **Anti-dsDNA**: An antibody against double-stranded DNA, often seen more during flares, especially in individuals with kidney involvement.
- **Anti-dsDNA**: An antibody against double-stranded DNA, often seen more during flares, especially in individuals with kidney involvement.
75
What is the third type of antibody that is less specific for lupus and targets proteins bound to phospholipids?
- **Antiphospholipid Antibody**: Targets proteins bound to phospholipids.
There are three types of antiphospholipid antibodies: **Anticardiolipin**, Lupus **Anticoagulant** (Lupus Antibody), and Anti-beta2 Glycoprotein I.
There are three types of antiphospholipid antibodies: **Anticardiolipin**, Lupus **Anticoagulant** (Lupus Antibody), and Anti-beta2 Glycoprotein I.
76
What complications can arise in individuals with lupus who develop antiphospholipid syndrome?
Individuals with lupus who develop **antiphospholipid syndrome**, where antiphospholipid antibodies cause a hypercoagulable state, are more prone to developing clots and may experience complications like deep vein thrombosis, stroke, and recurrent miscarriages.
77
What type of autoantibodies can be present in pregnant individuals with lupus and what risks are associated with them?
- **Anti-SSA or Anti-Ro Autoantibodies**: Pregnant individuals with lupus who are positive for these autoantibodies are at risk of having a newborn with **neonatal lupus erythematosus**. Manifestations may include congenital heart block, periorbital or diffuse rash, transaminitis (increased liver transaminases), and cytopenias at birth.
78
What is the significance of positive ANA and anti-histone antibodies with negative anti-dsDNA antibodies in the context of drug-induced lupus erythematosus?
Positive ANA and anti-histone antibodies with negative anti-dsDNA antibodies can be a clue for drug-induced lupus erythematosus. This condition develops as a reaction to certain medications metabolized by N-acetylation in the liver. The mnemonic "SHIPP" can help remember these medications: Sulfonamide, Hydralazine, Isoniazid, Procainamide, and Phenytoin.
79
What distinguishes drug-induced lupus from idiopathic lupus in terms of affected organs?
Drug-induced lupus **typically does not affect the oral mucosa, CNS, or kidneys, unlike idiopathic lupus.**
80
What is the key distinguishing feature between the joint deformities in lupus and rheumatoid arthritis?
Joint deformities in lupus are usually **non-erosive**, which can be seen on an X-ray.
81
What is the term used to describe patients with overlapping features of both lupus and rheumatoid arthritis, and what serological patterns are usually seen in such cases?
The term "rhupus" is used to describe patients with overlapping features of both lupus and rheumatoid arthritis. These patients usually have serologies consistent with both diseases, as well as erosive arthritis.
82
What autoimmune disorder, characterized by muscle inflammation, may be confused with lupus, and what is a key distinguishing feature of the associated rash?
Dermatomyositis is an autoimmune disorder that causes muscle inflammation. A key distinguishing feature of the associated rash is the heliotrope or lilac rash, which is a pruritic purplish rash that can appear on or around the eyelids. This rash is similar to the malar rash of individuals with lupus, but a key hint is that **it typically extends beyond the nasolabial folds, a region usually spared in lupus.**
83
In individuals presenting a discoid rash, what diagnostic tool may be necessary, and what are some differential diagnoses for a discoid rash?
Individuals presenting a discoid rash may require a skin biopsy showing autoantibody deposition. Differential diagnoses for a discoid rash include skin cancer, psoriasis, lichen planus, sarcoidosis, or syphilis.
84
What autoimmune disorder may share extraglandular manifestations with lupus, and how can they be distinguished?
Sjögren's syndrome may share extraglandular manifestations with lupus. The distinction is that **Sjögren's syndrome should also present with glandular manifestations like keratoconjunctivitis,
sicca, and
xerostomia.**
85
What medication can be helpful for arthritis and mucocutaneous symptoms in lupus?
Hydroxychloroquine and chloroquine can be helpful for arthritis and mucocutaneous symptoms in lupus.
86
What is a short-term, low-dose glucocorticoid that can be used in conjunction to treat acute flares in lupus?
Prednisone is a short-term, low-dose glucocorticoid that can be used in conjunction to treat acute flares in lupus.
87
What is a potential consequence of positive anticardiolipin antibodies in lupus, and how can it be misleading in diagnostics?
Positive anticardiolipin antibodies in lupus can cause a false-positive test, and it can be misleading in diagnostics as they are also present in people with syphilis, making it important to ensure that treponemal antibody testing is negative in lupus.
88
What are some immunosuppressant medications that may be used for serious or life-threatening cases of lupus, in conjunction with glucocorticoids?
Immunosuppressant medications like cyclophosphamide, azathioprine, or mycophenolate mofetil may be used in conjunction with glucocorticoids for serious or life-threatening cases of lupus.
89
How does the treatment approach differ between Mary and Kyle, who both have lupus but with different presentations?
Mary, with a discoid rash and less severe symptoms, can be treated as an outpatient with hydroxychloroquine or chloroquine and short-term glucocorticoids. Kyle, with lupus nephritis and a more aggressive presentation, needs in-hospital treatment with short-term high-dose glucocorticoids and may receive other immunosuppressive medications like cyclophosphamide.
