DefinitionRPR (rapid plasma reagin) is a screening test for syphilis. It measures substances (proteins) called antibodies that are present in the blood of people who may have the disease. Show
Alternative NamesRapid plasma reagin test; Syphilis screening test How the Test is PerformedA blood sample is needed. How to Prepare for the TestNo special preparation is usually needed. How the Test will FeelWhen the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away. Why the Test is PerformedThe RPR test can be used to screen for syphilis. It is used to screen people who have symptoms of sexually transmitted infections and is routinely used to screen pregnant women for the disease. The test is also used to see how treatment for syphilis is working. After treatment with antibiotics, the levels of syphilis antibodies should fall. These levels can be monitored with another RPR test. Unchanged or rising levels can mean a persistent infection. The test is similar to the venereal disease research laboratory (VDRL) test. Normal ResultsA negative test result is considered normal. However, the body does not always produce antibodies specifically in response to the syphilis bacteria, so the test is not always accurate. False-negatives may occur in people with early- and late-stage syphilis. More testing may be needed before ruling out syphilis. What Abnormal Results MeanA positive test result may mean that you have syphilis. If the screening test is positive, the next step is to confirm the diagnosis with a more specific test for syphilis, such as FTA-ABS. The FTA-ABS test will help distinguish between syphilis and other infections or conditions. How well the RPR test can detect syphilis depends on the stage of the infection. The test is most sensitive (almost 100%) during the middle stages of syphilis. It is less sensitive during the earlier and later stages of the infection. Some conditions may cause a false-positive test, including:
RisksThere is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others. Other risks associated with having blood drawn are slight, but may include:
ReferencesRadolf JD, Tramont EC, Salazar JC. Syphilis (Treponema pallidum). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 237. US Preventive Services Task Force (USPSTF); Bibbins-Domingo K, Grossman DC, et al. Screening for syphilis infection in nonpregnant adults and adolescents: US Preventive Services Task Force recommendation statement. JAMA. 2016;315(21):2321-2327. PMID: 27272583 www.ncbi.nlm.nih.gov/pubmed/27272583. Purified protein derivative standard; TB skin test; Tuberculin skin test; Mantoux test The PPD skin test is a method used to diagnose silent (latent) tuberculosis (TB) infection. PPD stands for purified protein derivative. Kidneys can be damaged by tuberculosis. Tuberculosis generally affects the lungs, but may cause infection in many other organs in the body. (Image courtesy of the Centers for Disease Control and Prevention.) Tuberculosis is caused by a group of organisms, Mycobacterium tuberculosis, M bovis, M africanum and a few other rarer subtypes. Tuberculosis usually appears as a lung (pulmonary) infection.
However, it may infect other organs in the body. Recently, antibiotic-resistant strains of tuberculosis have appeared. With increasing numbers of immunocompromised individuals with AIDS, and homeless people without medical care, tuberculosis is seen more frequently today. (Image courtesy of the Centers for Disease Control and Prevention.) The positive immunologic response to PPD antigen is seen here. The size of the papule is over 2 cm in diameter. The purified protein derivative is an antigen (a substance that stimulates the immune system to eliminate or fight foreign substances in the body), which is injected under the skin in the forearm. After 48 to 72 hours the injection site is evaluated by a physician. This skin test helps determine if a person has ever been infected by the microorganism
that causes tuberculosis. How the Test is PerformedYou will need two visits to your health care provider's office for this test. At the first visit, the provider will clean an area of your skin, usually the inside of your forearm. You will get a small shot (injection) that contains PPD. The needle is gently placed under the top layer of skin, causing a bump (welt) to form. This bump usually goes away in a few hours as the material is absorbed. After 48 to 72 hours, you must return to your provider's office (in some cases, this can be done virtually). Your provider will check the area to see if you have had a strong reaction to the test. How to Prepare for the TestThere is no special preparation for this test. Tell your provider if you have ever had a positive PPD skin test. If so, you should not have a repeat PPD test, except under unusual circumstances. Tell your provider if you have a medical condition or if you take certain medicines, such as steroids, which can affect your immune system. These situations may lead to inaccurate test results. Tell your provider if you have received the BCG vaccine and if so, when you received it. (This vaccine is only given outside of the United States). How the Test will FeelYou will feel a brief sting as the needle is inserted just below the skin surface. Why the Test is PerformedThis test is done to find out if you have ever come in contact with the bacteria that cause TB. TB is an easily spread (contagious) disease. It most often affects the lungs. The bacteria can remain inactive (dormant) in the lungs for many years. This situation is called latent TB. Most people in the United States who are infected with the bacteria do not have signs or symptoms of active TB. You are most likely to need this test if you:
Normal ResultsA negative reaction usually means you have never been infected with the bacteria that cause TB. With a negative reaction, the skin where you received the PPD test is not swollen, or the swelling is very small. This measurement is different for children, people with HIV, and other high-risk groups. The PPD skin test is not a perfect screening test. A few people infected with the bacteria that cause TB may not have a reaction. Also, diseases or medicines that weaken the immune system may cause a false-negative result. What Abnormal Results MeanAn abnormal (positive) result means you have been infected with the bacteria that cause TB. You may need treatment to lower the risk of the disease coming back (reactivation of the disease). A positive skin test does not mean that a person has active TB. More tests must be done to check whether there is active disease. A small reaction (5 mm of firm swelling at the site) is considered to be positive in people:
Larger reactions (larger than or equal to 10 mm) are considered positive in:
In people with no known risks of TB, 15 mm or more of firm swelling at the site indicates a positive reaction. People who were born outside the United States who have had a vaccine called BCG may have a false-positive test result. RisksThere is a very small risk for severe redness and swelling of the arm in people who have had a previous positive PPD test and who have the test again. Generally, people who have had a positive test in the past should not be retested. This reaction can also occur in a few people who have not been tested before. ReferencesFitzgerald DW, Sterling TR, Haas DW. Mycobacterium tuberculosis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 249. Rodino KG, Woods GL, Wengenack NL. Mycobacteria. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 59. Version InfoLast reviewed on: 11/23/2021 Reviewed by: Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. What are early signs and symptoms of inadequate oxygenation select all that apply?Below is a list of some of the signs that may indicate that a person is working harder to breathe and may not be getting enough oxygen.. Breathing rate. ... . Color changes. ... . Grunting. ... . Nose flaring. ... . Retractions. ... . Sweating. ... . Wheezing. ... . Body position.. Which conditions may cause pleural effusion select all that apply?The most common causes of transudative (watery fluid) pleural effusions include:. Heart failure.. Pulmonary embolism.. Cirrhosis.. Post open heart surgery.. Which factors would the nurse consider are causing a patients tachypnea?Tachypnea can be a symptom of sepsis or acidosis, such as diabetic ketoacidosis or metabolic acidosis. Patients with lung problems such as pneumonia, pleural effusion, pulmonary embolism, COPD, asthma, or an allergic reaction also present with tachypnea.
Which condition is associated with tachypnea and clubbing of the fingers?Respiratory diseases associated with finger clubbing include chronic obstructive pulmonary disease (COPD), lung cancer, cystic fibrosis (thick mucus in the throat and digestive tract), and bronchiectasis (destruction of the large airways).
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