Autoimmune Diseases Clinical Study Guide

A set of flashcards covering autoimmunity concepts, clinical presentations, mechanisms, and treatment strategies.

What is immunological tolerance?

The immune system's ability to recognize and NOT attack the body's own antigens.

What results from loss of tolerance in the immune system?

Autoimmune disease.

What is central tolerance?

The mechanism that deletes self-reactive T cells in the thymus and self-reactive B cells in the bone marrow.

What is peripheral tolerance?

Mechanisms that prevent self-reactive lymphocytes from activating in tissues.

How do genetic factors contribute to autoimmune diseases?

HLA associations determine susceptibility to autoimmune diseases.

What is Graves disease characterized by?

Hyperthyroidism due to TSI antibodies activating the TSH receptor.

How is Hashimoto's thyroiditis diagnosed?

Positive Anti-TPO antibodies and elevated TSH with low Free T4.

What is the hallmark symptom of Myasthenia Gravis?

Fluctuating muscle weakness that worsens with activity.

What diagnostic test is used for Myasthenia Gravis?

Positive anti-acetylcholine receptor (anti-AChR) antibodies.

What are the symptoms of Goodpasture syndrome?

Hemoptysis and rapidly progressive glomerulonephritis.

What is the mechanism of action for Autoimmune Hemolytic Anemia (AIHA)?

Autoantibodies against RBC surface antigens lead to extravascular or intravascular hemolysis.

What differentiates Warm AIHA from Cold AIHA?

Warm AIHA is mediated by IgG antibodies active at body temperature; Cold AIHA involves IgM antibodies active at cold temperatures.

What is a primary feature of Immune Thrombocytopenia (ITP)?

Isolated thrombocytopenia without splenomegaly.

What is the hallmark feature of Pernicious Anemia?

Autoantibodies against intrinsic factor leading to Vitamin B12 deficiency.

What is Systemic Lupus Erythematosus (SLE)?

A multi-system autoimmune disease characterized by a positive ANA test and various organ involvement.

What are the key features of SLE?

Fatigue, joint pain, photosensitivity, and malar rash.

What is the clinical significance of anti-dsDNA antibodies?

Highly specific for SLE and correlates with disease activity.

What laboratory findings are expected in Granulomatosis with Polyangiitis (GPA)?

Positive c-ANCA and clinical signs of respiratory and renal involvement.

What is the treatment for GPA?

Cyclophosphamide plus high-dose corticosteroids.

What defines Microscopic Polyangiitis (MPA) in terms of symptoms?

Pulmonary and renal involvement without upper respiratory symptoms.

What is the primary mechanism involved in Type 1 Diabetes Mellitus?

CD8+ T cells attack pancreatic beta cells leading to insulin deficiency.

What is the characteristic feature of Rheumatoid Arthritis (RA)?

Symmetric polyarthritis with morning stiffness lasting over an hour.

What are anti-CCP antibodies?

Highly specific antibodies for rheumatoid arthritis that can be positive before clinical symptoms.

What is the mechanism of Multiple Sclerosis (MS)?

T cells attack myelin in the CNS leading to demyelination.

What are the key visual findings in a patient with optic neuritis?

Sudden unilateral vision loss and pain with eye movement.

What distinguishes Crohn's Disease from Ulcerative Colitis?

Crohn's can affect the entire GI tract and presents with skip lesions, while UC is restricted to the colon with continuous inflammation.

What is the pathophysiology of celiac disease?”

T-cell mediated damage to the intestinal villi due to gluten leading to malabsorption.

What are the classic skin features of Dermatomyositis?

Heliotrope rash and Gottron's papules.

What is Mixed Connective Tissue Disease (MCTD)?

An overlap syndrome with features of multiple autoimmune diseases, primarily characterized by anti-U1 RNP antibodies.

What is Antiphospholipid Syndrome?

A condition associated with recurrent thrombotic events and pregnancy morbidities due to antiphospholipid antibodies.

What is the main therapy for Antiphospholipid Syndrome during pregnancy?

Aspirin plus heparin to reduce miscarriage risk.

What are the key differences between primary and secondary Sjögren Syndrome?

Primary occurs alone, while secondary is associated with other autoimmune diseases.

What is the function of Regulatory T cells (Tregs) in autoimmune diseases?

They suppress autoreactive immune responses to maintain tolerance.

What role do environmental triggers play in the development of autoimmune diseases?

Infections and drugs can induce autoimmune responses through mechanisms like molecular mimicry.

How do hormonal factors affect autoimmune disease prevalence?

Many autoimmune diseases are more common in females, potentially due to estrogen's effect on immune responses.

What is the definition of type III hypersensitivity?

Immune complex deposition leading to tissue damage through inflammation.

What symptom is highly associated with systemic lupus erythematosus?

Malar rash that spares the nasolabial folds.

What is the diagnostic criteria for systemic lupus erythematosus according to EULAR/ACR?

Positive ANA, and ≥10 points from clinical and immunologic criteria.

What laboratory finding is characteristic of Hashimoto's thyroiditis?

Positive Anti-TPO antibodies.

What is the mechanism behind Graves' disease?

Thyroid-stimulating immunoglobulin activates TSH receptors, causing hyperthyroidism.

What are the primary behaviors associated with Hyperthyroidism?

Weight loss, heat intolerance, and palpitations.

Which type of hypersensitivity is Myasthenia Gravis?

Type II hypersensitivity due to antibodies against acetylcholine receptors.

What differentiates the types of AIHA?

Warm AIHA primarily involves IgG and occurs at body temperature; Cold AIHA involves IgM and occurs in cold conditions.

What typical symptoms would one expect in a patient with autoimmune hemolytic anemia?

Fatigue, jaundice, dark urine, and splenomegaly.

What are peripheral nerve symptoms of Multiple Sclerosis (MS)?

Numbness, tingling, and weakness.

What specific antibodies would be tested in suspected RA?

Rheumatoid factor and anti-citrullinated peptide antibodies (anti-CCP).

How does treatment differ between Crohn's Disease and Ulcerative Colitis?

UC can be cured with colectomy, while Crohn's requires ongoing management.

What is a common symptom in both Crohn's Disease and Ulcerative Colitis?

Abdominal pain.

What specific part of the GI tract is chiefly affected in Crohn's Disease?

The terminal ileum is most commonly involved.

What is the primary treatment for Dermatomyositis?

Corticosteroids and immunosuppressive agents.

What specific laboratory finding suggests the presence of amyloidosis?

Congo red staining showing apple-green birefringence.

What is the primary cause of secondary amyloidosis?

Chronic inflammation from other conditions, such as rheumatoid arthritis.

What does the treatment for Anti-GBM disease involve?

Plasmapheresis and immunosuppressive therapy.

What are the consequences of autoimmune diseases on fertility?

They can lead to miscarriages and complications during pregnancy.

What type of rash is associated with Celiac Disease?

Dermatitis herpetiformis.

What is the common complication of long-standing Celiac Disease?

Enteropathy-associated T-cell lymphoma (EATL).

What is the significance of MALT lymphoma in association with Sjögren Syndrome?

Increased risk, particularly with new symptoms like parotid swelling.

What is a classic presentation for a patient with Celiac Disease?

Chronic diarrhea, bloating, and weight loss.

What is considered high yield when studying for autoimmune diseases?

Understanding the mechanisms, distinguishing clinical features, and key antibodies.

Why do autoimmune diseases have higher prevalence in females?

Hormonal factors, specifically the impact of estrogen on immune system function.

What does HLA typing indicate in autoimmune diseases?

Predisposition to specific autoimmune diseases.

Which autoantibody is most specific for SLE?

Anti-Smith antibody.

What is the importance of obtaining a biopsy in suspected autoimmune diseases?

To confirm diagnoses and assess organ involvement.

What is the primary focus when treating autoimmune diseases?

Suppressing the immune system while managing symptoms.

What are the high-yield comparisons to memorize for autoimmune diseases?

Differences in symptoms and lab findings for conditions like RA vs. OA and Crohn's vs. UC.

What is the term used to describe the anti-GBM antibodies in Goodpasture syndrome?

Anti-glomerular basement membrane antibodies.

What does positive ANCA indicate in testing?

Associated with various types of small vessel vasculitis.

Which autoimmune disease presents with joint pain and a characteristic malar rash?

Systemic lupus erythematosus (SLE).

What must be monitored closely in patients with systemic sclerosis (scleroderma)?

Pulmonary hypertension and renal function.

What is a common feature of Sjögren Syndrome?

Dry eyes (xerophthalmia) and dry mouth (xerostomia).

What is one potential indicator of an underlying autoimmune disease in a patient?

The presence of multiple autoimmune conditions in the same individual.

What are the two types of systemic sclerosis?

Limited and diffuse systemic sclerosis.

What treatment strategy helps with symptoms of Sjögren Syndrome?

Artificial tears and saliva substitutes.

What are the diagnostic tests for Celiac Disease?

Serological tests for anti-tTG and small bowel biopsy.

What are potential long-term complications of untreated Celiac Disease?

Lymphoma and osteoporosis due to malabsorption.

What method can be used to diagnose autoimmune diseases through skin examination?

Avoiding specific triggers and assessing skin lesions.

How can osteoarthritis be distinguished from rheumatoid arthritis?

RA is characterized by systemic symptoms and morning stiffness lasting over an hour.

What role do enzymes released from neutrophils play in autoimmune diseases?

They contribute to inflammation and tissue damage.

What factor is important when evaluating disease activity in autoimmune conditions?

Serological markers and clinical history.