The Frei test was developed in 1925 by Wilhelm Siegmund Frei, a German dermatologist, to identify lymphogranuloma venereum. Antigen made from sterile pus aspirated from previously unruptured

abscess An abscess is a collection of pus that has built up within the tissue of the body, usually caused by bacterial infection. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pre ...

es, produced a reaction in patients with lymphogranuloma venereum when injected intradermally. Other sources of antigen have been explored, most deriving from various tissues of mice infected with

Chlamydia Chlamydia, or more specifically a chlamydia infection, is a sexually transmitted infection caused by the bacterium ''Chlamydia trachomatis''. Most people who are infected have no symptoms. When symptoms do appear, they may occur only several w ...

. The test is no longer used but stands as a milestone in our understanding of immunology. A heat inactivated LGV 0.1ml grown in yolk sac of embryonated egg is injected intra dermally on the forearm and a control material prepared from noninfected yolk sac on the other forearm i.e. control. After 48–72 hours, an inflammatory nodule more than 6mm in diameter develops at the test site.

References

* W. Harris Connor, Edward A. Levin and E. E. Ecker. Observations on the Frei Test. ''The Journal of Infectious Diseases'', Vol. 60, No. 1 (Jan. - Feb., 1937), pp. 62–63 * Maurice J. Strauss, Marion E. Howard. The Frei Test for Lymphogranuloma Inguinale: Experiences with Antigens Made from Mouse Brain. ''J Am Med Assoc.'' 1936;106(7):517-520. *http://www.whonamedit.com/doctor.cfm/1407.html Skin tests {{med-diagnostic-stub