Antinuclear Antibodies and Systemic Autoimmune Rheumatic Diseases

A set of flashcards covering key concepts related to antinuclear antibodies, autoimmune diseases, and their diagnosis as presented in the lecture.

What are antinuclear antibodies (ANA's)?

Auto-antibodies that are specific for nuclear components of human cells.

What autoimmune diseases are associated with a positive ANA test?

Systemic lupus erythematosus (SLE), Sjogren syndrome (SjS), and systemic sclerosis (SSc).

What is SLE and what can it affect?

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease that can cause disease of the skin, heart, lungs, kidneys, joints, and/or nervous system.

What percentage of SLE patients show a positive ANA test?

Approximately 95% of patients with SLE will show a positive ANA test.

What is the most specific antinuclear antibody for SLE?

Double-stranded DNA (ds-DNA) antibodies.

What pattern do ds-DNA antibodies produce in tests?

A homogeneous staining pattern in indirect immunofluorescent tests.

What are anti-Sm antibodies and their significance?

Anti-Sm antibodies are produced in 20 to 40 percent of SLE patients and are highly specific for SLE.

What is Sjogren's Syndrome?

An autoimmune disease characterized by inflammation in the glands that produce moisture, leading to dryness in eyes and mouth.

What are the characteristics of scleroderma?

An autoimmune disease of connective tissue, characterized by fibrosis in the skin and organs.

What is the purpose of the antinuclear antibody test?

To qualitatively detect antinuclear antibodies in human serum.

What are the limitations of the ANA test?

Some drugs may induce ANA, a positive test is not a diagnosis of SLE, multiple patterns may be observed, and abnormal results may occur if slides dry.

What should be done after adding the serum sample in the ANA test?

The slide must be washed after the serum sample is added.

What are some clinical criteria for diagnosing SLE?

Malar rash, discoid rash, photosensitivity, ulcers, arthritis, kidney abnormalities, neurological disorders, blood disorders, and antinuclear antibodies. Four or more criteria suggest SLE.

What staining pattern is most typical of systemic lupus erythematosus?

A homogeneous staining pattern of the nucleus.

What is the process of preparing a slide for ANA testing?

Add serum samples, incubate, rinse, wash in PBS, add fluorescent reagent, and read under a fluorescent microscope.