1. In confirmation of Gaehtgens, syphilitic human sera give positive complement fixation with cultures of so called T. pallidum (Reiter strain). Syphilitic rabbit sera are equally reactive. Syphilitic human and rabbit sera agglutinate these cultures, often in high titre (Beck). 2. Normal rabbit sera react weakly with the culture to give both agglutination and complement fixation in low titre. Normal human sera, despite the fact that they contain agglutinins in low titre, fail to fix complement with the Reiter strain of cultured spirochetes. Confirming Gaehtgens, the latter reaction is therefore of practical utility for the serum diagnosis of syphilis. 3. When syphilitic serum is heated at 63°C., there is no demonstrable difference in the thermolability of the antibody to spirochetes, and of the reagin which determines the Wassermann and flocculation tests. 4. (a) The absorption of syphilitic serum by spirochetal suspensions removes all reactivity, not only for the spirochetes, but for tissue lipoids (alcoholic beef heart extract) as well; the sera become Wassermann- and flocculation-negative. (b) Absorption of syphilitic serum with tissue lipoids renders the Wassermann and flocculation tests negative, but does not demonstrably change the reactivity of the serum with spirochetes. (c) Rabbits immunized to beef heart lipoid develop spirochetal agglutinins and complement-fixing antibodies (Reiter strain) in high titre. 5. It is concluded that these cultured spirochetes contain antigenic material serologically related to a substance present in mammalian tissue, as well as other antigenic factors not present in such extracts, but equally reactive with syphilitic serum. 6. These findings support the thesis that the primary serologic change in syphilis is the development of antibodies to T. pallidum. The Wassermann and flocculation tests would be explained on the basis that the tissue extracts used as "antigen" in these tests contain one or more substances serologically related to antigenic components of T. pallidum. Similarly, the cultured Reiter strain of spirochete is apparently sufficiently close serologically to T. pallidum to be agglutinated by and to give complement fixation with the antibodies to T. pallidum present in syphilitic serum. 7. Since suspensions of cultured spirochetes contain antigenic factors which react specifically with syphilitic serum, some of which are not present in ordinary Wassermann and flocculation "antigens," they may prove even more valuable than those tissue extracts in the serodiagnosis of syphilis.
Sera from patients with proven cases of syphilis were tested for the presence of antibodies to structurally important phospholipids by using qualitative and quantitative assays. All 47 sera examined qualitatively contained antibodies to cardiolipin, phosphatidic acid, and phosphatidylserine, but not antibodies to other selected phospholipids. Such reactivity was not found in normal (Red Cross) sera. Although the degree of antibody binding to phospholipids varied in individual sera, reactivity was almost always greater with cardiolipin than with phosphatidic acid or phosphatidylserine. Binding saturability was found in sera as the cardiolipin concentration was increased over a constant area of nitrocellulose paper. Anti-cardiolipin binding measured by the protein A method gave results similar to the results measured by using anti-immunoglobulin G, which supports the conclusion that binding was to the Fab portion of the immunoglobulin molecule. When measured as a function of serum concentration and plotted in double-reciprocal fashion, the anti-cardiolipin binding data for two syphilitic sera had similar Kd values but different Bmax values. Stoichiometric calculations indicated that approximately 11,000 to 16,000 mol of cardiolipin appeared to be bound per mole of labeled second antibody. These observations may mean that the anti-cardiolipin antibody does not recognize the individual cardiolipin molecule as the antigenic site but recognizes some structural form of the phospholipid or that steric hindrance related to the interaction of the phospholipid with nitrocellulose paper prevented the bulk of cardiolipin molecules from reaching. The structural specificity of the antibodies identified excludes the possibility that these antibodies are directed against the phosphodiester linkage. These findings should give impetus to future study of a potential pathogenic or marker role for these antibodies in syphilis and in other syndromes in which membrane damage may be a primary event.
Stimulation of the rabbit reticuloendothelial system with viable Mycobacterium bovis (strain BCG), and other agents, had no effect on the development of syphilitic lesions after intradermal or intravenous inoculation with graded doses of Treponema pallidum (virulent Nichol's strain; mean infective doses less than 10). The simultaneous administration of immune syphilitic rabbit serum retarded the development of lesions, but this appeared to be due solely to the immune serum, suggesting no synergism between the activated reticuloendothelial system and the anti-T. pallidum antibodies. The administration of two doses of BCG enhanced syphilitic lesion development in the rabbit.
Consecutive serum samples were obtained from patients with syphilis before and on three occasions after treatment. The sera contained immunosuppresive factors associated with the immunoglobulin fraction, which could depress the natural killer cell activity of healthy controls. There was no evidence that allogeneic or lymphocytotoxic antibodies played a role in immuno-suppression, which could be reproduced with both soluble and insoluble antigen-IgG-antibody complexes.
A case of congenital syphilis which presented with paroxysmal cold haemoglobinuria is described.
The patient had aortic incompetence, and the significance of this finding is discussed.
The Coombs test was studied, and positive results appear to be due to interaction between antiglobulin serum and complement adsorbed on to the test cells, this adsorption being promoted by the cold antibodies.
We experienced a rare case of solitary syphilitic osteomyelitis of the skull without any other clinical signs or symptoms of syphilis. A 20-year-old man was referred due to intermittent headache and mild tenderness at the right parietal area of the skull with a palpable coin-sized lesion of softened cortical bone. On radiological studies, the lesion was a radiolucent well enhanced mass (17 mm in diameter). The erythrocyte sedimentation rate (52 mm/h) and C-reactive protein (2.24 mg/dL) were elevated on admission. Serum venereal disease research laboratory (VDRL) and Treponema pallidum haemagglutination assay (TPHA) tests were positive. There were no clinical signs or symptoms of syphilis. After treatment with benzathine penicillin, we removed the lesion and performed cranioplasty. The pathologic finding of the skull lesion was fibrous proliferation with lymphoplasmocytic infiltration forming an osteolytic lesion. In addition, a spirochete was identified using the Warthin-starry stain. The polymerase chain reaction study showed a positive band for Treponema pallidum. Solitary osteomyelitis of the skull can be the initial presenting pathological lesion of syphilis.
Infectious osteomyelitis; Syphilis; Skull; Treponema pallidum
In the course of routine postmortem examinations of rabbits infected with Treponema pallidum, six cases of pronounced granulomatous myocarditis were encountered. Treponemata were not demonstrated in the lesions, but the clinical history, and the gross and microscopic appearance of the lesions seemed to warrant a diagnosis of syphilitic myocarditis. The lesions measured 1.0 cm. or more in diameter and histologically were practically identical with those described by Warthin in cases of syphilitic myocarditis in man. These are the first cases of syphilitic myocarditis or of visceral syphilis in the rabbit that have been reported.
Syphilitic proctitis is a rare disease. It usually presents as proctitis, ulcer and neoplasm but lacks pathognomonic clinical symptoms. It is, therefore, difficult to diagnose and is occasionally treated inappropriately. We report the case of a 51-year-old man who had a hard, ulcerated mass, which occupied the circumference of the rectal wall and which mimicked a rectal tumor. Fortunately, positive finding from routine toluidine red unheated serum test and treponema pallidum particle agglutination tests made us reevaluate the patient and led us to suspect syphilitic proctitis. This diagnosis was finally confirmed after successful penicillin G benzathine therapy which made surgery unnecessary.
Syphilis; Rectum; Proctitis; Rectal cancer; Treponema pallidum
Syphilis is an infectious disease that can cause a wide variety of ocular signs. One of the rarest manifestations of ocular syphilis is acute syphilitic posterior placoid chorioretinitis (ASPPC). We report on the spectral-domain optical coherence tomography (SD-OCT) features of a case diagnosed with unilateral ASPPC.
A 64-year-old man presented with a sudden loss of visual acuity (VA) in the right eye. His only clinical sign was a large, geographic, yellow-white lesion centered on the right fovea. Our patient was studied with SD-OCT on presentation and during follow-up, as well as with fluorescein and indocyanine green angiography, electrophysiological study, and serologic and autoimmune screening.
Laboratory workup revealed positive serology for active syphilis and elevated anti-beta2 glycoprotein I antibodies. SD-OCT showed a marked distortion of both the choroidal and outer retinal architecture. After treatment, best-corrected VA improved to 20/25. Pattern electroretinography displayed a severe reduction of P50 amplitude, which improved in late follow-up. Six months after presentation, VA was 20/25 and anti-beta2 glycoprotein I antibodies returned to normal levels.
Our findings are compatible with immunologically mediated temporary physiological impairment of the neuroretina, since the changes seen by SD-OCT could not have normalized if they were due to anatomical injury. The results of our study provide clues to understanding the pathogenesis of this disease and allow us to define a characteristic temporal sequence of events in ASPPC.
Syphilis; Placoid; Chorioretinitis; Spectral-domain optical coherence tomography; Beta2 glycoprotein
These experiments show: 1. That the surface tension of normal blood serum is considerably lowered by standing undisturbed for a period of 1 hour (time-drop). 2. That the greatest time-drop recorded is with serum diluted approximately 10,000 times in fresh serum, and 50,000 times in heated serum. 3. That immune serum is not affected in the same manner by heat as is normal serum. Syphilitic serum and anti-sheep cell rabbit serum behave similarly in this respect. 4. That serum albumin is much more readily soluble in alkaline buffer solutions than globulin is, and that globulin from normal serum ionizes more than that from syphilitic serum. Further investigations are being made in an effort to determine why the proteins aggregate or dissociate under the influence of the factors under consideration.
1. When an emulsion containing virulent Treponema pallidum is added to serum from normal rabbits and from untreated immune syphilitic rabbits that have been infected with a homologous strain of T. pallidum the mixture incubated at 37°C., and injected intracutaneously into normal rabbits, typical syphilitic lesions commonly develop at the sites of inoculation of the normal serum-spirochete mixture, while at the sites of inoculation of immune serum-spirochete mixtures usually either no lesion develops or else the incubation period of the resulting lesions is shorter and the lesions remain smaller than those produced by normal serum-spirochete mixtures. 2. In a series of preliminary experiments, of 56 areas inoculated with serum-spirochete mixtures, in 42 the suppressive action of the syphilitic serum was manifest, in 10 areas questionable evidence of protection was noted, and in 4 areas there was no evidence that the syphilitic serum had exerted a suppressive or protective action. 3. The protective action of syphilitic serum seems to have been lessened by heating to 56°C. 4. The results of the protection test in three other series of experiments were as follows: (a) Of 12 areas in 6 rabbits inoculated with normal serum-spirochete mixtures typical syphilitic lesions developed, while in the same number of areas inoculated with immune serum-spirochete mixtures there was complete or partial suppression of lesions in all. (b) Of 45 areas inoculated with serum from 10 different immune syphilitic rabbits, definite evidence of protection was observed in 37, questionable evidence in 5, and no evidence of protection in 3. (c) Of 8 areas in 4 rabbits inoculated with immune serum-spirochete mixtures no lesions developed during the period of observation, while of 8 areas in the same rabbits inoculated with one of two normal serum-spirochete mixtures typical syphilitic lesions developed in each.
Pooled serum from hamsters immune to syphilitic infection conferred complete protection on recipient hamsters challenged with Treponema pallidum subsp. endemicum. Cutaneous lesions did not develop, and the recipients' lymph nodes weighed less than those of controls and contained no treponemes. Treponemicidal activity in the pooled immune serum was relatively high. When treponemes were incubated in immune serum and complement and the suspension was then inoculated into hamsters, recipients developed neither lesions nor enlarged lymph nodes teeming with treponemes. With hamsters already infected for several weeks, however, immune serum failed to impair or influence the progression of syphilis. Treponemes were eliminated only when immune serum was administered within a short time of syphilitic infection. These results demonstrate that hamsters develop an effective serum-mediated treponemicidal response, but this response is not sufficient to eliminate treponemes at the primary foci of infection.
The utility of sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting as a serological tool in the diagnosis of human syphilitic infections was examined. In model experiments, rabbits were immunized with Treponema pallidum or T phagedenis, and the antisera were tested for cross-reactivities with both sets of antigens. A major T. pallidum antigen with a molecular weight of ca. 17,000 appeared to be the most reliable specific antigenic marker as assessed by the immunoblotting technique with peroxidase-labeled second antibodies. Antibodies to this antigen were never detected in hyperimmune rabbit anti-T. phagedenis sera or in the sera of nonsyphilitic humans. In contrast, reactive antibodies were found in all syphilitic human sera and also in liquor samples that were positive in the passive hemagglutination test. Differentiation between immunoglobulin M and immunoglobulin G antibodies was directly possible by applying the respective specific second antibodies. Immunoblotting tests were performed with sera exhibiting low passive hemagglutination test titers and equivocal fluorescent treponemal antibody and rapid plasma reagin card reactions. In more than 60% of these cases, immunoblot positivity with respect to the 17,000-molecular-weight antigen was found. The same results were obtained with partially purified 17,000-molecular-weight antigen. The immunoblot technique should be useful as an additional diagnostic tool for differentiating between true and false-positive serological reactions.
The time course of antibody synthesis during syphilis was studied in experimentally infected rabbits. A rapid antibody response was seen; the rabbits became positive in both the rapid plasma reagin (RPR) test and Treponema pallidum haemagglutination assay (TPHA) by nine days after infection. Treponemal immobilising antibodies were also seen as early as nine days after infection. Antibody inhibition of treponemal attachment to baby rabbit genital organ (BRGO) cells in culture occurred with immune sera taken 30 days after infection but not earlier. When T pallidum was mixed with immune syphilitic rabbit sera taken at different stages of the infection and used to infect normal rabbits the rabbits became partially resistant to T pallidum only when the treponemes were mixed with sera taken at least 30 days after syphilitic infection. This appearance correlated well with the development of antibodies which blocked attachment of T pallidum to host cells. These antibodies may be involved in the resistance to reinfection which develops in syphilis as the disease progresses.
A previously described toxic factor associated with Treponema pallidum (Nichols) and found in extracts of syphilitic rabbit testes has now also been detected in syphilitic rabbit serum. The toxic factor, which inhibits DNA synthesis in baby rabbit genital organ (BRGO) cells in vitro, is present in rabbit serum up to 30 days after infection with T pallidum.
Treponema pallida were extracted from rabbit testicular syphilomas and suspended in a special medium in which the organisms remain motile and infectious for several days. On incubation of such suspensions with syphilitic rabbit or human sera and guinea pig complement, the treponemes became non-motile and lost their capacity to infect rabbits. Various factors affecting this immobilization have been investigated. In a preliminary survey of individual sera, immobilizing antibody could be detected in the majority of sera from syphilitic animals and human beings, but was absent in almost all the normal sera examined. It could be demonstrated that the immobilizing and reagin activities of syphilis sera are due to separate antibodies.
The rate of clearance of virulent Treponema pallidum (Nichols) from the blood stream of normal rabbits and rabbits previously treated with Mycobacterium bovis BCG was similar, there being treponemes still circulating 8 h after intravenous inoculation. In contrast, immune syphilitic rabbits cleared the virulent treponemes within 1 to 2 hours. Rabbits with passive humoral immunity to T. pallidum (after the transfer of 70 ml of immune serum) showed a similar clearance rate to that of the immune rabbits. Rabbits previously treated with BCG and with passive humoral immunity did not show a synergistic enhanced clearance rate, it being similar to that of immune rabbits.
Cobra venom factor, an agent commonly used to deplete complement, lowered the resistance of hamsters to infection with Treponema pallidum subsp. endemicum , as shown by a more rapid development of cutaneous lesions in infected animals treated with cobra venom factor than in infected, untreated animals. Cobra venom factor also abrogated the passive transfer of resistance by injection of serum from syphilitic immune hamsters. These results indicate that complement influences the pathogenesis of treponemal infection.
Rabbits developed chancre immunity 5.0 to 7.5 weeks after intradermal infection with 10(3) Treponema pallidum (Nichols). The serological response against T. pallidum antigen during this 2.5-week period was examined by Western immunoblotting. Sera from rabbits infected for 5.0 weeks contained antibodies against 7 of 13 major T. pallidum immunogens, with strongest binding detected against a polypeptide of Mr 47,000. By 7.5 weeks of infection, syphilitic rabbit sera recognized 10 of 13 antigens; the most evident increase in serological reactivity was directed against a polypeptide of Mr 45,000, suggesting that the development of a strong serological response against this polypeptide correlated with the onset of chancre immunity.
The inbred LSH/Se LAK strain of hamster can be infected with Treponema pallidum Bosnia A, the causative agent of endemic syphilis. When infected, this strain consistently produced extensive chronic skin lesions that persisted for 6 to 9 months, even in the presence of peak antitreponemal antibody titers. The lymph nodes increased in weight and contained measurable numbers of treponemes. This infection also gave the hamster cross-immunity to T. pallidum Nichols and Treponema pertenue, the causative agents of venereal syphilis and frambesia, respectively. LSH hamsters are thus an excellent model to study the immune response mechanisms to syphilitic infection.
TR-b is a Reiter treponeme antigen, cross-reacting with an antigen in Treponema pallidum (Nichols pathogenic strain). Sera from patients with secondary syphilis contain precipitating antibodies against TR-b. The isolation of TR-b from a bacterial sonic extract is described here. It involved five fractionation steps: anion-exchange chromatography (DE-52 Whatman), gel filtration (Ac-A-22 Ultrogel), and affinity chromatography on phenyl-Sepharose CL 4B, iminodiacetic acid-Sepharose CL 4B, and lysine-Sepharose 4B, respectively. The purified TR-b was enriched 199 times compared with the starting material, and the recovery was 12%. TR-b was shown to be a protein; it did not bind to a series of lectins, and by gel filtration and polyacrylamide gel electrophoresis, the molecular weight was determined to be 610,000 to 630,000. It was found by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to be composed of identical 70,000-dalton subunits. The isolated TR-b was immunologically pure when tested in crossed immunoelectrophoresis against polyspecific anti-Reiter immunoglobulin. The purified TR-b antigen was used for the production of a monospecific rabbit antiserum, giving strong fluorescence with both the Reiter treponeme and T. pallidum in an indirect immunofluorescence test.
The 83-kDa receptor protein of Treponema pallidum (TpN83) recognizes and binds fibronectin (Fn) at the amino acid sequence RGD site. By using experimentally infected animals, we have demonstrated that immunoglobulin G antibodies to this antigen and autoantibodies to the RGD site of Fn are putative components of immune complexes. This, and other findings, led us to initially hypothesize that anti-idiotypes (anti-Id) of an anti-TpN83 response are autoantibodies to RGD. Alternatively, we reasoned that if anti-Fn autoantibodies played a role in the pathogenesis of syphilis, then down-regulation of such a response by the Id network might directly affect progression of the disease. To test the hypothesis, rabbits were immunized with either affinity-purified TpN83 antigen or the synthetic Fn-7 peptide, KYGRGDS, and subsequently challenged with T. pallidum. Compared with results obtained with unimmunized, control rabbits, accelerated lesion development was noted in the rabbits immunized with TpN83. Pronounced, though unexpected, differences with respect to lesion development and progression were noted in the animals immunized with Fn-7 and then challenged intravenously; a minimal number of lesions appeared with a delayed onset. These lesions, like the localized chancres seen following intradermal challenge, were smaller and minimally ulcerated, and they healed rapidly. The Fn-7-immunized rabbits all differed from the controls in that anti-Id to anti-RGD F(ab')2 were demonstrable within 4 weeks following infection; decreases in anti-Fn autoantibody levels were associated with concomitant increases in anti-Id levels. Immunoglobulin Gs (anti-Id) from these animals following elution from anti-RGD F(ab')2 immunoaffinity columns also reacted with affinity-purified TpN83 antigen in immunoassays. These results suggest that down-regulation of autoreactive clones by manipulation of the idiotypic network in experimental syphilis warrants further investigation.
Three examples of non-syphilitic paroxysmal cold haemoglobinuria (PCH) in children are described which occurred, within a period of 16 days, in association with a febrile illness. No definite viral aetiology or obvious epidemiological association could be established. A Donath-Landsteiner antibody of anti-P specificity was demonstrated in all three patients. The serological aspects of PCH are critically discussed.
BACKGROUND--IgG antibodies from mothers adequately treated for syphilis can cross the placenta and appear in the sera of healthy newborns without infection. In such infants, a false diagnosis of congenital syphilis is often made. We have designed a retrospective survey to determine the time of seroreversion of the serological tests for syphilis (STS) in uninfected newborns born to mothers who were adequately treated for syphilis. MATERIALS AND METHODS--Fifty two seropositive, untreated newborns born to 51 mothers treated for syphilis were studied. The newborns were followed at 1, 3, 6, 9, and 12 months of age until seroreversion was detected. The VDRL test was followed until 12 months in 12 of the 22 newborns who were positive at birth, the TPHA in 21 of the 46 newborns, and the FTA-ABS test in 22 of the 48 newborns. RESULTS--In the first serological tests done within 1 month after birth, the VDRL was positive in 22 newborns (42%), the TPHA in 46 (88%), and FTA-ABS in 48 (92%). The VDRL seroreverted within 6 months after birth in 84%, and within 1 year in 100%. The TPHA test seroreverted in 95% within 1 year after birth. The FTA-ABS test seroreverted in 100% within 1 year after birth. CONCLUSIONS--In most seropositive, untreated newborns born to treated mothers the VDRL became negative within 6 months after birth and the TPHA and FTA-ABS within 1 year. This result is consistent with current Centers for Disease Control (CDC) guidelines. However, although the CDC guidelines are adequate in general, we think that some revision is desirable concerning the IgM test and combination of the test results in order to rule out congenital syphilis in seropositive, nonsymptomatic newborns born to the treated mothers.
A case is reported of secondary syphilis with ocular signs in a patient who had antibodies to human immunodeficiency virus (HIV) and hepatitis B infections and from whose urine cytomegalovirus was cultivated. Treatment with penicillin resulted in rapid recovery from his retinitis and uveitis. The case highlights the importance of testing for syphilis in all patients with HIV infection.