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1.
Treponema pallidum can be detected by conventional techniques such as dark-field microscopy, immunofluorescence or the rabbit infectivity test, in large numbers in the skin lesions of primary and early secondary syphilis. In the skin lesions of late secondary and tertiary syphilis, conventional techniques fail to detect spirochaetes in general, perhaps due to increasing degeneration and the disappearance of treponemal spirochaetes in late syphilitic skin lesions. We used the highly sensitive technique of polymerase chain reaction (PCR) to prove the presence of Treponema pallidum-specific DNA in six lesions of late secondary syphilis and seven lesions of tertiary syphilis, including one syphilitic gumma. A Whartin-Starry stain was carried out in all 13 specimens and did not reveal any treponemal structures. Treponema pallidum-specific DNA was amplified by PCR in four of six cases of secondary syphilis and in the syphilitic gumma. These results are in favour of a direct cell-mediated immune reaction directed against treponemal antigen rather than the concept of an Id-reaction. Beside the usefulness of a PCR-based assay for understanding the aetiology of lesions of late syphilis, the assay described can be of clinical importance in various situations where traditional methods fail to detect Treponema pallidum because of lack of sensitivity.  相似文献   

2.
The species Treponema pallidum includes three subspecies (pallidum, pertenue, and endemicum) that cause syphilis, yaws, and bejel, respectively. A closely related species, Treponema paraluiscuniculi, is the etiologic agent of venereal syphilis in rabbits but does not infect humans. Although these treponemes cause distinct diseases, no laboratory method for differentiation has been reported. Genetic signatures were defined in the 5' and 3' flanking regions of the 15-kDa lipoprotein gene (tpp15) that distinguish the human pathogens and T. paraluiscuniculi, as well as distinguishing T. pallidum subsp. pallidum from the causes of human nonvenereal treponematoses. A single Eco47III restriction site in the 5' flanking region differentiates T. pallidum subsp. pallidum from the other subspecies and species, and an XcmI site in the 3' flanking region differentiates T. paraluiscuniculi from the human pathogens. Polymerase chain reaction methods and restriction polymorphism were used to analyze 27 strains of pathogenic Treponema species.  相似文献   

3.
There are increasing reports of unusual clinical features and atypical courses of syphilis in patients with acquired immunodeficiency syndrome. Recently, we had the opportunity to study an HIV-positive female patient with strong manifestations of secondary syphilis. The case is discussed together with the implications of secondary syphilis in her concomitant ocular affliction. Moreover, we comment on the clinico-therapeutic controversies brought about by the association of infection with Treponema pallidum and HIV.  相似文献   

4.
The role of lysozyme in the immune immobilisation of Treponema pallidum is not yet fully understood. The T. pallidum immobilisation assay was used to demonstrate that the immobilisation and lysis of T. pallidum in vitro by antibodies (serum, IgG fraction or IgM fraction) and complement proceed in a lysozyme-independent mode. In the presence of lysozyme the rate of immobilisation increased. In contrast with its effect on Escherichia coli, the effect of lysozyme on T. pallidum was governed exclusively by its enzymic activity rather than by the cationic protein nature of the molecule. Lysozyme, released from stimulated phagocytes, induced formation of lysozyme antibodies in 59.6% of syphilis patients as determined by lysozyme antibody ELISA. The highest frequency was found in patients with untreated secondary syphilis, whereas untreated primary syphilis was only rarely accompanied by the presence of lysozyme antibodies. Cross-reactivities between lysozyme and treponemal antigens were excluded by immunoblotting. The autoantibodies did not influence the lysozyme activity. It was concluded that the formation of lysozyme antibodies is only an epiphenomenon in the host defence against treponemal infection.  相似文献   

5.
It is common to examine the cerebrospinal fluid in untreated or inadequately treated asymptomatic patients with a reactive serum fluorescent treponemal antibody absorption (FTA-ABS) test before initiating antibiotic therapy for syphilis. This prospective study evaluated the usefulness of such examination. Four hundred thirty-two patients over 40 years old, reporting for annual physical examination, had a serum FTA-ABS test. Thirty-seven (8.6%) patients and 2 of 4 spouses were reactive repeatedly. Of the 39 patients with reactive tests, 7 had a history of penicillin therapy for syphilis, 5 had received heavy metal therapy, and 27 had no history of syphilis. These 39 patients had a neurological examination, serum VDRL, Treponema pallidum immobilization (TPI), and repeat FTA-ABS tests by two other laboratories. The TPI test was reactive in 30 (77%). Four had nonspecific neurological signs. Routine CSF examination (cells, total protein, VDRL, glucose, IgG%) on 30 patients with a history of inadequate treatment had a low diagnostic yield. Two patients had an unexplained total protein elevation (57 and 61 mg/dl) and 1 had a mildly increased IgG% (15%). All cell counts, VDRL tests, and glucose levels were normal. Agarose electrophoresis demonstrated one or more CSF immunoglobulin bands in 10 (36%) of 28 patients, possibly representing an immunological marker of past or latent central nervous system infection.  相似文献   

6.
This work reports a comparison of an enzyme immunoassay (EIA) using two major Treponema pallidum recombinant antigens with a T. pallidum hemagglutination (TPHA) assay and a nontreponemal Venereal Disease Reference Laboratory (VDRL) test. A total of 1,822 normal donor serum samples was tested for cardiolipin and T. pallidum antibodies, respectively, by the VDRL assay and EIA. Among these samples, 440 were further tested by TPHA technology. Four samples were found positive by EIA, while all were reported to be negative by both TPHA and VDRL routine assays. Subsequent testing of EIA-positive samples confirmed 100% (four of four samples) and 25% (one of four samples) positive results, respectively, by immunofluorescence assay and a Western blot (immunoblot) syphilis kit. The sensitivity of the recombinant EIA was estimated at virtually 100% with a reference panel of 50 syphilitic samples. According to this study, the newly developed EIA kit shows 100% sensitivity combined to a specificity greater than 99.8% for detecting treponemal immunoglobulin G antibodies in blood bank syphilis screening.  相似文献   

7.
A 15-year-old boy, whose history revealed an unremarkable pregnancy, birth and neonatal period and who had shown a normal motor and mental development, presented at the hospital with deterioration of cognitive functions since the age of 7. He was bedridden with manifest ataxia involving all limbs, anisocoria and a sluggish to absent pupil reaction to light. Syphilis serology was positive with a Venereal Disease Research Laboratory (VDRL) titer of 1:256 and a Treponema pallidum Haemagglutination Assay (TPHA) titer of 1:163840. Cerebrospinal fluid (CSF) protein concentration was 55 mg/dl and CSF-leucocyte count was 14/mm3 (85% mononuclear cells). CSF-VDRL-titer was 1:16. A diagnosis of congenitally acquired dementia paralytica was made, since the boy's parents' clinical exam and serology results were suggestive for latent syphilis. Although cognition was still very much deteriorated five months following penicillin treatment, clinical examination revealed partial recuperation. Screening for syphilis should be part of routine testing in every subject presenting with cognitive deterioration, regardless of age.  相似文献   

8.
Infectious syphilis, caused by the spirochete bacterium Treponema pallidum subsp. pallidum, remains a public health concern worldwide. The immune-response evasion mechanisms employed by T. pallidum are poorly understood, and prior attempts to identify immunoprotective antigens for subsequent vaccine design have been unsuccessful. Previous investigations conducted in our laboratory identified the T. pallidum glycerophosphodiester phosphodiesterase as a potential immunoprotective antigen by using a differential immunologic expression library screen. In studies reported here, heterologous expression of the T. pallidum glycerophosphodiester phosphodiesterase in Escherichia coli yielded a full-length, enzymatically active protein. Characterization of the recombinant molecule showed it to be bifunctional, in that it exhibited specific binding to human immunoglobulin A (IgA), IgD, and IgG in addition to possessing enzymatic activity. IgG fractionation studies revealed specific binding of the recombinant enzyme to the Fc fragment of human IgG, a characteristic that may play a role in enabling the syphilis spirochete to evade the host immune response. In further investigations, immunization with the recombinant enzyme significantly protected rabbits from subsequent T. pallidum challenge, altering lesion development at the sites of challenge. In all cases, animals immunized with the recombinant molecule developed atypical pale, flat, slightly indurated, and nonulcerative reactions at the challenge sites that resolved before lesions appeared in the control animals. Although protection in the immunized rabbits was incomplete, as demonstrated by the presence of T. pallidum in the rabbit infectivity test, glycerophosphodiester phosphodiesterase nevertheless represents a significantly immunoprotective T. pallidum antigen and thus may be useful for inclusion in an antigen cocktail vaccine for syphilis.  相似文献   

9.
As the causative agent of the common sexually transmitted disease syphilis and a fastidious, microaerophilic obligate parasite of humans, Treponema pallidum subsp. pallidum is one of the few prominent infectious agents that has not been cultured continuously in vitro. T pallidum therefore represents an attractive candidate for genomic sequencing. Preliminary sequence results from the 1.13 million base pair genome are consistent with the expected limited metabolic capabilities of this spirochete, but indicate that the bacterium may express toxins and surface proteins that have not been identified previously.  相似文献   

10.
Syphilis is an unexpected diagnosis in the stomach. To establish the diagnosis, evidence of Treponema pallidum in the gastric lesion is necessary. However, it is sometimes difficult to prove the presence of the organisms by conventional methods. The authors describe two cases of early gastric syphilis with pseudolymphomatous histology in which T pallidum gene was detected by the polymerase chain reaction (PCR) using paraffin biopsy sections. The gastric lesion of each case endoscopically and histologically simulated that of malignant lymphoma. However, no clonality was proved by immunohistochemistry or PCR gene rearrangement analysis. No spirochetal organisms were detected with certainty by Warthin-Starry silver stain, whereas the organisms were shown by immunofluorescent stain in one patient. A PCR study showed the treponemal DNA in both patients, and its validity was supported by a direct sequencing and a restriction enzyme digestion. Positive results of serological tests for syphilis and regression of the lesions after antisyphilitic treatment were confirmatory of the diagnosis. Gastric syphilis should be considered as a differential diagnosis when an atypical lymphoid infiltrate fails to show monoclonality. The present PCR method would be helpful in showing T pallidum using routinely processed small biopsy specimens as the tissue source.  相似文献   

11.
We present a case of a patient coinfected with syphilis and the human immunodeficiency virus (HIV) who had unusual and severe cutaneous ulceration. The profound immune defects associated with HIV may lead to an altered clinical presentation and a more aggressive course in patients infected with Treponema pallidum. Despite non-confirmatory histological findings, we feel our patient's cutaneous ulcers probably represent superficial gummata, which have failed to resolve completely following currently accepted high-dose antisyphilis chemotherapy.  相似文献   

12.
Community based survey on a sample of commercial sex workers in one red light area of Calcutta, was carried out to determine prevalence of sexually transmitted diseases (STD) including HIV infection and related risk factors. An alarmingly high prevalence of STDs (80.56 per cent) but low HIV-seropositivity (1.13 per cent) was observed. Candida albicans, Neisseria gonorrhoeae and Trichomonas vaginalis were detected in 23.24, 13.24 and 11.11 per cent of genital specimens respectively. BY TPHA test 62.97 per cent of the sera were reactive for Treponema pallidum. Duration in the profession of sex workers was found to have an association with seropositivity for syphilis. Prevalence of HIV infection might be low at present, but conditions were highly favourable for rapid spread of infection.  相似文献   

13.
To determine the usefulness of cerebrospinal fluid (CSF) tests for syphilis at a large academic hospital, clinical and laboratory data on 644 patients in whom such testing was requested over a 12-month period were analysed. In 198 cases (31%) the Treponema pallidum haemagglutination (TPHA) screening test could not be performed because of insufficient fluid. Thirty-eight of the remaining patients were diagnosed as having active neurosyphilis. Examination of 22 files of patients who had a positive TPHA and fluorescent treponemal antibody absorption (FTA-Abs) test together with a negative CSF Venereal Disease Research Laboratory (VDRL) test revealed that other CSF measures indicating disease activity (CSF protein, cells or IgG index) were not utilised optimally. In 10 (45%) of these patients neurosyphilis was not diagnosed despite either abnormal or incomplete CSF biochemical analysis, indicating that if the CSF VDRL is used as the sole marker for disease activity, some cases of neurosyphilis are likely to be missed.  相似文献   

14.
Although penicillin still remains highly effective for syphilis, concerns have been raised that current regimens may be inadequate for the treatment of early syphilis. We report the failure of benzathine penicillin in the treatment of secondary syphilis. Extensive tracing of sexual contact history failed to identify sources of possible reinfection; therefore, we believe that this case represents a treatment failure and an ensuing relapse of secondary syphilis.  相似文献   

15.
OBJECTIVES: To determine the rate of concordance of the Microhemagglutination Assay for Antibodies to T. pallidum (MHA-TP) and the Fluorescent Treponemal Antibody-Absorption test (FTA-ABS) prior to therapy in patients with early stage syphilis and to assess the incidence of and associated risk factors for seroreversion of these treponemal specific tests during the first year after therapy for early syphilis. DESIGN: Multicenter, prospective, cohort treatment study of patients with early syphilis. METHODS: Five hundred twenty-five patients were enrolled in a study to evaluate the response of early syphilis to either benzathine penicillin 2.4 million units intramuscularly once or this therapy plus amoxicillin 2 g and probenecid 500 mg orally both three times daily for 10 days. Serologic and clinical follow-up was conducted at intervals over 1 year. MHA-TP and FTA-ABS tests were performed on serologic specimens from each patient visit. RESULTS: Enrollment specimens showed 5% discordant MHA-TP and FTA-ABS results with 85% of these demonstrating a nonreactive MHA-TP. This occurred most commonly in primary syphilis. In patients who had a 1-year serologic follow-up with FTA-ABS or MHA-TP, seroreversion occurred in 9% and 5% of cases, respectively. No association between HIV-seropositivity and TST seroreversion was demonstrated. CONCLUSION: The MHA-TP may be less sensitive than the FTA-ABS for identifying patients with primary syphilis. Treponemal specific tests may become nonreactive during the first year after therapy for early syphilis.  相似文献   

16.
17.
BACKGROUND AND OBJECTIVES: To determine the prevalence rates of serological reactivity of Haemophilus (H.) ducreyi, Treponema pallidum, and herpes simplex virus type 2 (HSV-2) antibodies among female sex workers (FSWs) and their association with human immunodeficiency virus (HIV) antibody status. STUDY DESIGN: Cross-sectional, standard serological assays were used for syphilis, HSV-2 and HIV; a modified enzyme-linked immunosorbent assay (ELISA) was used to detect specific anti-H. ducreyi immunoglobulin (Ig) G and IgA antibodies. RESULTS: Seroprevalence rates were 86% for anti-H. ducreyi IgG and 69% for anti-H. ducreyi IgA; 4% for rapid plasma reagin (RPR) and Treponema palladium hemagglutination assay (TPHA) confirmed syphilis; 59% for HSV-2; 12% for HIV-1 and 2% for HIV-2. Lower-class FSWs were significantly more likely than upper-class FSWs to be H. ducreyi seropositive (IgG: OR = 42.7; IgA: OR = 7.6) and have current or past syphilis infection (RPR: OR = 3.5; RPR and TPHA: OR = 4.5). The presence of syphilis increased significantly with older age (P-trend < 0.001). Non-Nigerian FSWs had significantly higher reactivity to chancroid (IgG: OR = 3.5; IgA: OR = 1.8) and borderline reactivity to syphilis (RPR: OR = 1.6; TPHA: OR = 2.0). A history of sex with non-Nigerian Africans was significantly associated with chancroid reactivity and borderline significant with syphilis serostatus. H. ducreyi seropositivity was significantly more likely in FSWs with HSV-2 (OR = 2.4) and syphilis (OR = 5.6). Chancroid and HSV-2 antibodies were also more common in HIV-infected FSWs. CONCLUSION: The prevalence of H. ducreyi antibodies is the highest rate that has been reported. Our findings underscore the importance of an effective program to control GUDs as part of the strategy to prevent the potentially explosive spread of HIV in Nigeria.  相似文献   

18.
A multiplex polymerase chain reaction (M-PCR) assay that simultaneously detects the three major causes of genital ulcer disease (GUD), Haemophilus ducreyi, Treponema pallidum, and herpes simplex virus, was used to evaluate swab specimens for 38 sequential patients with GUD at a Thai sexually transmitted disease clinic. Subjects received clinical diagnoses and syndromic treatment. Swab specimens for H. ducreyi cultures and M-PCR were obtained. No H. ducreyi cultures were positive. Of 38 M-PCR specimens, 31 (81.6%) were positive for HSV, 1 (2.3%) for both HSV and T. pallidum, and none for H. ducreyi or T. pallidum alone; 6 (15.8%) were negative for all 3 pathogens. Clinical diagnoses corresponded poorly to M-PCR findings; none of 5 suspected cases of chancroid were positive by M-PCR and none of 1 for syphilis, but 21 of 24 suspected herpes lesions were confirmed by M-PCR. Human immunodeficiency virus infection status was known for 24 of 38 subjects; 11 (45.8%) were seropositive, and all 11 had HSV by M-PCR. HSV appeared to be the most common pathogen overall.  相似文献   

19.
To examine the extent of infection with syphilis in an inner-city community, we determined the prevalence, incidence, and correlates of syphilis seroreactivity in a representative sample of unmarried whites, African Americans, and Hispanics living in San Francisco during 1988 to 1989 and again 1 year later in 1989 to 1990. One thousand seven hundred seventy single men and women aged 20 to 44 were surveyed in a random household sample drawn from three neighborhoods of varying geographic and cultural characteristics. Syphilitic infection was determined by testing specimens with the microhemagglutination assay for antibodies to Treponema pallidum (MHA-TP). Of blood samples available from 1262 participants from the initial survey, 32 (2.5%) were MHA-TP reactive. After adjustment for age, a reactive syphilis serology was significantly predicted (P < 0.05) by African American race, homosexual activity (men), and less education. In homosexually active men, lifetime number of male sex partners and the presence of antibody to the human immunodeficiency virus (HIV) significantly predicted syphilis seroreactivity (P < 0.01). One year later, of 841 specimens available for testing, an additional 13 (1.5%) had become MHA-TP reactive. Eleven (85%) of the new cases were in heterosexual men and women. Although San Francisco citywide incidence data indicate that syphilis may be decreasing for the city as a whole, incidence data on a community level suggests that syphilitic infection is increasing in high-risk heterosexual communities. Thus, syphilis prevention programs should rely on serologic testing at the community level to plan effective intervention strategies.  相似文献   

20.
BACKGROUND: Syphilis remains a significant cause of morbidity in many developing countries and in some areas within North America and Europe. Mathematical models of the transmission dynamics of sexually transmitted infections have provided insights of relevance both to the interpretation of observed epidemiological patterns and to the design of control programs. Their use for the study of syphilis has been limited to date. GOALS AND STUDY DESIGN: The authors investigated the transmission dynamics of syphilis against a template based on the natural history of infection in individual patients with the aim of (1) identifying gaps in our understanding of the biology of infection, and (2) providing insights of relevance to the design of control policies. RESULTS: Analyses reveal that Treponema pallidum has a moderate to high probability of transmission during contact between susceptible and infectious sexual partners. This, combined with questions over the existence of any immunity to reinfection, helps to ensure the long-term persistence of syphilis within "core" activity groups. Patterns of treatment in North America are shown to have significantly altered the relative frequency of individuals in the different stages of disease. CONCLUSIONS: The analyses emphasize the benefits to be gained from treating infected people early in the primary stage of infection to reduce the effective period during which infected people can transmit to others. This form of treatment is beneficial for both the individual and the community. Treatment has greatly altered the incidence of different disease stages, but the full implications of treatment depend on whether immunity is present.  相似文献   

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