Categories Sexual Health

Diagnosis of syphilis

Diagnosis of syphilis

Syphilis is a sexually transmitted disease caused by bronchial bacteria. These bacteria are species that can not be grown in the laboratory because of their small size so that they can not be seen under the light microscope. Serological tests are the ideal way to detect all Syphilis stages.

Diagnosis of syphilis

  • If suspected syphilis is suspected, nontreponemal tests should be performed; a Rapid Plasma Regain (RPR) and Venereal Disease Research Laboratory (VDRL)
The sensitivity of these two tests is estimated to be 78-86% for primary syphilis, 100% for secondary syphilis and 95-98% for trigeminal syphilis. The specificity of these tests is between 85-99%. VDRL is positive after 1-2 weeks of chancre, and nontreponemal tests are ineffective over time after treatment.
  • Because the test result can be false positive, as in systemic lupus erythematosus patients with syphilis that does not cause syphilis, the result should be ascertained by a treponemal test, Such as fluorescent troponemal antibody-absorption (FTA-ABS), Treponema pallidum hemagglutination (TPHA) and other tests.
  • FTA-ABS is a confirmed test for VDRL, and the sensitivity of the FTA-ABS is 84% ​​for primary disease infection and approximately 100% for disease detection in other stages. %.
  • The dark-field microscopy is used to examine skin lesions in primary or secondary syphilis.
  • It is possible to do the same tests for cerebrospinal fluid, which is characterized by high sensitivity and low sensitivity, in addition to the work of analysis of spinal fluid to confirm the presence of syphilis nervosa.
  • Radiology can be used to assist in diagnosis; normal chest radiographs show the expansion of the aorta, and the stratified image and magnetic resonance imaging of the head and body are used to follow the complications of trigeminal syphilis.
  • The histological examination of skin ulcers (chancre) is shown. It shows the penetration of lymphocytes, plasma cells, cells around the blood vessels, and the boundary between the layers of the skin, as well as the proliferation of cells lining the capillaries, and we can see blockages in these blood vessels.