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Show f. Clin. Neuro-ophthalmol. 3: 3-4, 1983. Editorial Syphilitic Optic Atrophy The article "Progressive Visual Loss in Syphilitic Optical Atrophy" by Sacks, Osher, and Elconin in this issue, raises again the question of ocular and neurological involvement in late syphilis. The subject was discussed in an editorial in the June 1982 issue of this journal as well as in a review article by Prof. Pierre Collart in that issue. The article by Sacks et al. emphasizes that this disease is still with us, and also provides evidence that antibody formation was occurring within the central nervous system in that patient, and further emphasizes that the dose of penicilln therapy for late syphilis is really unknown at this time. The point that I should like to address here, however, is the pathogenesis of syphilitic optic atrophy, and the mechanisms whereby one may encounter a pale disc in this disease. Dr. Sacks and associates emphasize the occurrence of optic atrophy following syphilitic optic neuritis and perineuritis, or as described in the older literature as "secondary" optic atrophy. In such instances, one certainly would agree with the assumption that vision loss would be unusual after the atrophic stage had occurred following an initially swollen disc. However, it is probably pertinent to review some of the older literature with regards to "primary optic atrophy" in syphilis and also some of the statements about "tabetic optic atrophy." In Dr. Walsh's second edition, Clinical Neuro-ophthalmology (1957), there is a more expanded section of ocular and neurosyphilis than appeared in the later editions, and some important points are made about "tabetic optic atrophy." The following quotes are relevant at this point. "The visual disturbances usually appear with the onset of atrophy and increase as the atrophy increases, but there are instances in which the discs may be pale for as long as four or five years before the visual functions are affected (Uhthoff). The loss of vision progressed with extreme rapidity in some cases.... The loss of vision may be slowly progressive as we have observed in many instances." "Moore and his coworkers stated that of 249 untreated patients 70% were blind within three years, 90% within five years, and all within nine years. Their criterion of blindness was anything below 10/200 in the better eye." The statement was also made that "gradual loss of vision is more frequently observed as it is characterized almost invariably by concentric nar- March 1983 rowing of the visual fields." I would recommend to the reader that an excellent review would be obtained by reading pages 541-601 in Dr. Walsh's second edition. Two classic papers also to be noted are: L.L. Sloan and A.c. Woods: "Perimetric Studies in Syphilitic Optic Neuropathies." Arch. Ophthalrnol. 20: 201, 1938; and A.c. Woods. "Syphilis of the Eye." Am. ]. Syphil. Gonor. Yen. Dis. 27: 133, 1943. Finally, Syphilitic Optic Atrophy by Walter L. Bruetsch, Charles C Thomas Co., Springfield, Illinois, 1953, offers a complete, thorough review of the subject. An excellent recent review is the chapter on "Syphilis" by Dr. King K. Holmes, chapter 146, pages 716-726, in Harrison's Principles of Internal Medicine (9th ed.), McGraw-Hill Book Co., 1980. The importance of this subject to the practitioner needs additional emphasis. According to the United States Department of Health and Human Services, in 1957, there were 6,251 reported cases of infectious syphilis. However in 1977, there were 20,352 reported cases of infectious syphilis. Furthermore, in 1977, in addition to these 20,000 cases of primary and secondary syphilis, an additional 21,297 cases of early latent syphilis were reported. These facts gain additional emphasis when it is recalled that many cases of syphilis seen by practitioners are not reported. Of 43 million blood tests done in the United States in 1977, 1.5 million were reactive (3.5%). Over half of all reported early syphilis cases were detected as a direct result of either contact tracing or serologic testing. Another significant point is that of all men with infectious or early latent syphilis interviewed in the United States between 1977 and 1978, half were known to be homosexual or bisexual. A helpful mnemonic in syphilis is known as the "rule of sixes." The Bible speaking of a man known as "the beast," makes an interesting statement (Revelations 13:17-18) "And that no man might buy or sell, save he that had the mark, or the name of the beast, or the number of his name. Here is wisdom. Let him that hath understanding count the number of the beast: for it is the number of a man; and his number is Six hundred threescore and six." If one remembers that number-666-it may be helpful when considering the following points, which were obtained from Dr. Holmes's excellent article (in general). 3 4 Editorial: Syphilitic Optic Atrophy The Rule of Sixes in Syphilis 1. Treponema pallidum has six spirals 2. It is six microns long 3. It is made of six fibrils 4. Each fibril has six laminas on electron microscopy 5. Within six weeks from exposure, the primary lesion appears 6. The chancre persists up to six weeks 7. Six weeks after healing of the chancre, secondary syphilis appears 8. Secondary stage subsides within six weeks, and patient enters the latent stage. 9. Six point five percent of untreated cases develop symptomatic neurosyphilis 10. Sixteen percent develop benign tertiary syphilis 11. Aortitis is found in up to 60% of untreated cases at autopsy 12. Six indications for serum FTA-ASS test are: light-near dissociation of the pupil, optic atrophy, uveitis, retinitis pigmen-tosa, interstitial keratitis, and dislocated lens 13. There are six letters in FTA-ASS test The point to be emphasized here is that syphilis may involve the optic nerve in many different routes. It may produce a primary intraocular optic neuritis, a vascular occlusion picture on the disc, or as in primary optic atrophy, it often begins in the arachnoid spaces around the optic nerve in its intracranial portion, just distal to the chiasm, and then spreads peripherally in the optic nerve sheath. It can also produce syphilitic optochiasmatic arachnoiditis. Patients can have syphilitic primary optic atrophy without presenting clinical signs or symptoms of tabes dorsalis. Sruetsch also points out that syphilitic optic atrophy can be progressing in patIents with normal cerebrospinal fluid examinations. The clinician is again reminded of the importance of obtaining a serum FTA-ASS test in any patient with otherwise unexplained optic atrophy. J. Lawton Smith, M.D. Journal of Clinical Neuro-ophthalmo!ogy |