Judith A. Fisher and Douglas J. Ivins
In the practice of cost-effective medicine, no value is seen to routine laboratory testing. An antinuclear antibody titer (ANA) should only be ordered in cases of a clinical suspicion of a rheumatologic disease (also known as connective tissue disorder) (1–2).
The patient may present with vague complaints of malaise, aches, or skin rash. On the other hand, the complaint may be of a red, hot, or swollen joint or joints. If a rheumatologic disease is suspected, an ANA can be ordered. It is important to remember that the specificity of a positive ANA titer for all rheumatic diseases is only 50% (3). With that in mind, ANA titers of more than 1/160 may be significant (1). The characteristic staining patterns associated with ANAs can be helpful. Homogeneous (diffuse) and speckled patterns are relatively nonspecific.
Peripheral patterns are often seen in systemic lupus erythematosus. Nucleolar patterns are more typical for scleroderma. A mildly elevated ANA and no disease process (falsely positive ANA) is found in 5% of young adults and in 18% of individuals aged more than 65 years (1).
The history and physical examination will help to place the patient into one of several diagnostic categories (Table 17.3).
It is important to remember to order an ANA only with a clinical suspicion of a disease process in which the ANA value plays a significant role.
References
1. Jacobs D. Laboratory test handbook, 3rd ed. Hudson, OH: Lexi-Comp, Inc., 1994:
638–640.
2. Nakamura R. Clinical diagnosis and management by laboratory methods, 4th ed. Philadelphia: WB Saunders, 1996:1013–1023.
3. Wallach J. Interpretation of diagnostic tests, 6th ed. Boston: Little, Brown, and Company, 1996:817–820.
Review other book chapters online related to Antiphospholipid syndrome:
Copyright notice for book excerpts: Copyright © 2008 Lippincott Williams & Wilkins. All rights reserved.
|
More About This Book:
Title: The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter Authors: Robert B. Taylor (editor) Publisher: Lippincott Williams & Wilkins Copyright: 2000 ISBN: 0-78172-094-X 
|
|
What do you think about the features of this website? Take our user survey and have your say:
Next articles:
Tools & Services:
Medical Articles:
Search Specialists by State and City
By using this site you agree to our Terms of Use. Information provided on this site is for informational purposes only; it is not intended as a substitute for advice from your own medical team. The information on this site is not to be used for diagnosing or treating any health concerns you may have - please contact your physician or health care professional for all your medical needs. Please see our Terms of Use.
Copyright © 2009 Health Grades Inc. All rights reserved.
