Treponemal specific tests for the serodiagnosis of syphilis. Syphilis and HIV Study Group

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.     

Maternal and congenital syphilis

Testing for syphilis during pregnancy reveals a positive serologic status in 0.02% of cases. However, a 66% rate of stillbirths is noted in women who are infected and who have not benefited from any treatment. Routine screening is at present performed during the early stages of pregnancy but a second serologic test during the third trimester is useful in the diagnosis of a late infection especially in drug users or HIV (human immunodeficiency virus) positive patients. Congenital syphilis is diagnosed in utero when a positive maternal serologic status is associated with ultrasound images showing fetal abnormalities; these include hepatosplenomegaly, hyperechogenic bowel, signs of bowel obstruction or fetal hydrops. Maternal syphilis is treated by delayed action penicillin and is indicated even for patients allergic to the antibiotic which in this particular case is delivered after desensitization. First line therapy by intravenous penicillin is indicated when confronted with the following high risk factors of congenital syphilis: an elevated titre of VDRL (venereal disease research laboratory) at the time of diagnosis or delivery, unknown date of the precise onset of the infection, the appearance of a rash or of a chancre during pregnancy, ultrasound fetal abnormalities or late therapy during the third trimester. Treatment of the new-born child will depend on the results of clinical, serologic and X-ray evaluation. Long term follow-up for at least a year is mandatory.     

Prevalence, incidence, and correlates of syphilis seroreactivity in multiethnic San Francisco neighborhoods

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.     

Human immunodeficiency virus seropositivity in adolescents with syphilis

OBJECTIVE: The purpose of this study was to assess the relationship between syphilis and human immunodeficiency virus (HIV) infection among inner-city, minority group adolescents. METHODS: From August 1989 through June 1990, serum from all positive serologic tests for syphilis, obtained from patients attending a comprehensive adolescent health center in an acquired immunodeficiency syndrome epicenter and its two school-based clinics, were frozen without patient identifiers and were subsequently screened for HIV by enzyme-linked immunosorbent assay with confirmatory Western blot for positives. In addition, a retrospective chart review was performed for all patients with a positive serologic test for syphilis during the study period. RESULTS: Of the 59 specimens with a positive syphilis serologic test, 9 (15.3%) were HIV seropositive. Of the patients with syphilis, 57.4% were black and 42.6% were Hispanic; 16.4% were male (mean age 18.1) and 83.6% were female (mean age 17.8). Only 1 subject (female) was an injection drug user; 4 of the male subjects self-identified as having had sex with other males. Of the subjects, 27.8% had primary, 19.7% had secondary, and 52.5% had latent syphilis at the time of diagnosis. A prior or concurrent sexually transmitted disease was present in 90% of the males and 80% of the females; gonorrhea was the most prevalent sexually transmitted disease in the males (89%) and chlamydia was most prevalent in the females (35%). A history of chancroid and/or herpes was present in 16.4% of the subjects. CONCLUSIONS: It is concluded that the diagnosis of syphilis in an adolescent is a risk factor for HIV infection. All sexually active adolescents should be routinely screened for syphilis, regardless of sexual practices. Those with syphilis should be specifically counseled about their increased risk for HIV infection and the importance of consistent condom use, and they should be referred for formal HIV pretest counseling.     

Syphilitic labial leucokeratosis

BACKGROUND: Several diagnoses, including syphilis, can be entertained in patients with leukokeratosis of the buccal mucosa. We report a case of labial leucokeratosis which revealed latent syphilis. CASE REPORT: A 36-year-old man with a past history of genital syphilis chancre which have been treated 12 years earlier, developed buccal leucokeratosis with no other clinical manifestation. Histology showed dermal infiltration containing plasma cells, polynuclears and lymphocytes. Blood tests were positive for syphilis. Complementary examinations were unable to detect another localization. Leucokeratosis regressed completely after one injection of Extencilline. There has been no recurrence at one year. DISCUSSION: The clinical and histological presentations of syphilis can mimic different skin diseases. Serodiagnosis alone is significant. Isolated buccal lesions are rarely described in syphilis suggesting serodiagnosis should always be ordered. Whatever the clinical stage of the diseases, serological surveillance after treatment for syphilis is essential.     

Alterations of Descemet's membrane in interstitial keratitis

Twenty corneas from patients with interstitial keratitis were examined by light microscopy and one of these by electron microscopy. Seventy percent of patients had either a positive serologic test for syphilis or a history of treatment for syphilis. Focal or diffuse multilaminar thickening of Descemet's membrane with secondary linear guttata was present in 88% of cases. Confluent linear cornea guttata formed retrocorneal hyaline ridges that clinically showed a central gray core surrounded by a translucent sheath. Microscopically, these ridges consisted of concentric laminations of newly formed Descemet's membrane. Some ridges hung into the anterior chamber as a bow-like strand or a spiderweb network. A possible pathogenetic sequence may include (1) inflammatory insult to a relatively young endothelium; (2) alteration of endothelial function to fibroblast-like activity; (3) the production of abnormal basement membrane and other collagenous material and formation of a new multilaminar Descemet's membrane; and (4) separation of some ridges from the multilaminar Descemet's membrane to hang into the anterior chamber as strands and networks.     

The kinetics of antibodies against hepatitis C virus may predict viral clearance in exposed hemophiliacs

Several studies have reported the spontaneous loss of hepatitis C virus (HCV) antibodies in HCV-exposed persons. However, the relationship between seroreversion and spontaneous virus clearance has yet to be precisely determined in a single homogeneous population of untreated immunocompetent patients. In this study, 32 human immunodeficiency virus-seronegative hemophiliacs who had been exposed to HCV were followed for a mean duration of 141 months; 22 remained chronic carriers (68.8%). All but 1 of the nonviremic patients (90.0%) showed partial (8 cases) or complete (2 cases) seroreversion. In contrast, all but 1 of the viremic patients (95.1%) had a stable serologic profile when analyzed by a recombinant immunoblot assay. The results indicate that any HCV antibody-positive immunocompetent patient with no detectable serum HCV RNA and normal alanine aminotransferase values and whose serial samples show a progressive decrease in the level of HCV antibodies present may be considered as having a resolved infection.     

Syphilis management and treatment

Syphilis poses a serious health problem in many developing countries and in some areas of North America and Europe, especially Eastern Europe. This article initially addresses the state of the art regarding the interaction between syphilis and HIV infection and its consequences for management and treatment. Further attention is given to laboratory diagnosis of syphilis and false-positive and false-negative serologic reactions. The diagnosis and management of neurosyphilis, ocular, cardiovascular, and congenital syphilis are addressed, as well as management of syphilis patients allergic to penicillin and the Jarisch-Herxheimer reaction. Finally, the role of partner(s) and contact tracing is discussed.     

Congenital syphilitic skeletal manifestations in a premature infant revisited

Increasing rates of congenital syphilis have been reported in recent years despite the availability of adequate therapy. In our perinatal-neonatal center, approximately 1.5% of newborns have reactive serologic tests for syphilis. Untreated or partly treated maternal syphilis can adversely affect neonatal outcome since the treponeme can cross the placenta at any time during pregnancy. As a result of hematogenous placental transmission, neonatal manifestations are usually systemic and similar to the secondary stage of syphilis, and include hepatosplenomegaly, jaundice, neurosyphilis, and skeletal changes. A case of early congenital syphilis in an extremely premature infant with primary skeletal involvement is presented.     

Levels of engagement in hospital and community-based homes for people with learning disabilities: can individual characteristics account for differences?

BACKGROUND: There is controversy over whether tardive dyskinesia (TD) is solely a consequence of antipsychotic drug treatment or in part may reflect an intrinsic aspect of the disease process. Pathophysiologic factors could, independently or in concert with drug effects, lead to the development of dyskinetic signs. METHODS: We studied prospectively 118 patients in their first episode of psychosis who were treatment-naive or had less than 12 weeks of antipsychotic drug exposure at study entry. Patients received standardized antipsychotic drug treatment and were evaluated for up to 8 1/2 years with regular assessments of psychopathologic signs and symptoms and side effects. RESULTS: The cumulative incidence of presumptive TD was 6.3% after 1 year of follow-up, 11.5% after 2 years, 13.7% after 3 years, and 17.5% after 4 years. Persistent TD had a cumulative incidence of 4.8% after 1 year, 7.2% after 2 years, and 15.6% after 4 years. Taken individually, both antipsychotic drug dose, entered as a time-dependent covariate, and poor response to treatment of the first psychotic episode were significant predicters of time to TD. When antipsychotic drug dose and treatment response were examined together, treatment responders had significantly lower hazards for presumptive TD than nonresponders (hazard ratio, 0.29; 95% confidence interval, 0.09 to 0.97). Dose was a trend-level predicter, with each 100-mg chlorpromazine equivalent unit increase in dose associated with a 5% increase in the hazard of presumptive TD (hazard ratio, 1.05; 95% confidence interval, 0.99 to 1.11). CONCLUSION: Poor response to the treatment of a first episode of psychosis and, to a lesser extent, antipsychotic drug dose are important factors in the development of TD. This suggests that there may be a disease-related vulnerability to TD manifest with antipsychotic drug exposure. Potential pathophysiologic factors might include neurodevelopmentally induced structural neuropathologic characteristics, sensitization of nigrostriatal dopamine neurons, and the induction of glutamatergically mediated neurotoxic effects.     

The adequate stimulus for avian short latency vestibular responses to linear translation

Transient linear acceleration stimuli have been shown to elicit eighth nerve vestibular compound action potentials in birds and mammals. The present study was undertaken to better define the nature of the adequate stimulus for neurons generating the response in the chicken (Gallus domesticus). In particular, the study evaluated the question of whether the neurons studied are most sensitive to the maximum level of linear acceleration achieved or to the rate of change in acceleration (da/dt, or jerk). To do this, vestibular response thresholds were measured as a function of stimulus onset slope. Traditional computer signal averaging was used to record responses to pulsed linear acceleration stimuli. Stimulus onset slope was systematically varied. Acceleration thresholds decreased with increasing stimulus onset slope (decreasing stimulus rise time). When stimuli were expressed in units of jerk (g/ms), thresholds were virtually constant for all stimulus rise times. Moreover, stimuli having identical jerk magnitudes but widely varying peak acceleration levels produced virtually identical responses. Vestibular response thresholds, latencies and amplitudes appear to be determined strictly by stimulus jerk magnitudes. Stimulus attributes such as peak acceleration or rise time alone do not provide sufficient information to predict response parameter quantities. Indeed, the major response parameters were shown to be virtually independent of peak acceleration levels or rise time when these stimulus features were isolated and considered separately. It is concluded that the neurons generating short latency vestibular evoked potentials do so as "jerk encoders" in the chicken. Primary afferents classified as "irregular", and which traditionally fall into the broad category of "dynamic" or "phasic" neurons, would seem to be the most likely candidates for the neural generators of short latency vestibular compound action potentials.     

Collaborative study of a semiautomated method for the analysis of prednisolone and prednisone tablets

A simple, adequately evaluated serologic test is not now available for use in gonorrhea screening programs. Some of the factors responsible for the relatively low sensitivity and specificity of serologic tests for gonorrhea as compared to cultural techniques are discussed. These include the time required for development of an immunologic response after infection, cross-reactivity with other antigens, and the persistence of antibody after therapy. At present, gonococcal serologic tests may be useful to the clinician in establishing the diagnosis of disseminated gonococcal infection, especially if paired sera demonstrate a change in antibody titer. Current research on the antigenic structure of the gonococcus may lead to the development of improved serologic tests for use in screening programs. However, the performance of any test may vary according to sex of the patient, presence of symptoms, history of prior gonococcal infection, and duration of the current infection. The physician must understand these factors when considering the use of any serologic test for gonorrhea.     

Safety of influenza vaccine in heart transplant recipients

BACKGROUND: Influenza vaccine is recommended for heart transplant recipients, but its administration is often deferred because of anecdotal reports of rejection associated with the vaccine. We evaluated the safety of influenza vaccine in a group of stable heart transplant recipients over a 2-year period. METHODS: During the 1993 to 1994 influenza season, stable heart transplant recipients who had undergone transplantation a minimum of 1 year before study entry were randomized to vaccination with a single dose of influenza vaccine versus no vaccination. Routine endomyocardial biopsies and postvaccination influenza serologic studies were performed between 2 and 6 weeks after enrollment/immunization. During the 1994 to 1995 season, patients were given 2 doses of influenza vaccine, separated by 3 weeks; endomyocardial biopsies and serologic studies were performed between 2 and 6 weeks after the second immunization or enrollment (if control subject). Biopsy results were evaluated with respect to vaccine response, immunosuppressive regimens, and patient demographics. RESULTS: Eighteen patients were enrolled in the single vaccine trial and 10 in the booster vaccine trial. Four of 14 vaccine recipients had biopsy specimens consistent with International Society for Heart and Lung Transplantation grades 2 to 3A as compared with 1 of 14 control subjects (grade 2) (p = .326). All episodes of rejection in the vaccine recipients were asymptomatic and responded to a single course of treatment. Rejection was unrelated to the time from transplantation, doses of immunosuppression, age, or number of doses of or response to vaccine. CONCLUSIONS: Influenza vaccine can be safely administered to most heart transplant recipients but may be associated with low-level histologic rejection.     

Mapping numerical magnitudes along the right lines: Differentiating between scale and bias.

Previous investigations on the subjective scale of numerical representations assumed that the scale type can be inferred directly from stimulus–response mapping. This is not a valid assumption, as mapping from the subjective scale into behavior may be nonlinear and/or distorted by response bias. Here we present a method for differentiating between logarithmic and linear hypotheses robust to the effect of distorting processes. The method exploits the idea that a scale is defined by transformational rules and that combinatorial operations with stimulus magnitudes should be closed under admissible transformations on the subjective scale. The method was implemented with novel variants of the number line task. In the line-marking task, participants marked the position of an Arabic numeral within an interval defined by various starting numbers and lengths. In the line construction task, participants constructed an interval given its part. Two alternative approaches to the data analysis, numerical and analytical, were used to evaluate the linear and log components. Our results are consistent with the linear hypothesis about the subjective scale with responses affected by a bias to overestimate small magnitudes and underestimate large magnitudes. We also observed that in the line-marking task, participants tended to overestimate as the interval start increased, and in the line construction task, they tended to overconstruct as the interval length increased. This finding suggests that magnitudes were encoded differently in the 2 tasks: in terms of their absolute magnitudes in the line-marking task and in terms of numerical differences in the line construction task. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

基于DEM的露天矿坑坡面顶底线自动提取方法研究

针对露天矿坑坡面顶底线传统提取方法存在的低效率问题,提出了一种从露天矿坑DEM(数字高程模型,Digital Elevation Model)三维模型中自动提取坡顶底线的方法.首先对原始三维模型数据进行双边滤波预处理,进行去噪并保留特征点;其次根据高程值的标准差设定阈值后将DEM三维模型转化为灰度图像;最后采用梯度运算...     

Relapsing syphilis

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.     

A case of ventricular septal perforation treated surgically with an infarction exclusion technique

We report an 85-year-old woman with postinfarction interventricular septal perforation. She underwent successful emergent surgical treatment by a slightly modified method based on David-Komeda's procedure. Perforation in this case occurred four days after acute myocardial infarction. Preoperative Qp/Qs was 2.58, and pulmonary artery pressure was 34/25 mmHg. The area of infarction was large, and the perforation was the linear type 2.5 cm long near the apex. A probe was not able to pass through the perforation due to its complicated configuration. A double Xenomedica patch was sutured on the left side of the interventricular septum without excising the infarcted area. The suture line was placed on healthy myocardium apart from the infarcted area. The Xenomedica patch was sandwiched between the closure line of the ventriculotomy. Four days after surgery, residual shunt was observed by echocardiogram, but this subsequently disappeared on the 17th postoperative day. The patient was discharged from our hospital on the 57th postoperative day, and is now doing quite well.     

Thermodynamic data from diffusion couples—I

A non linear least squares based method is presented to estimate activity data from measured interdiffusivity data for isomorphous binary metals. The interdiffusion coefficient is modelled as a product of two functions, one representing the thermodynamic contributions and another the contribution of the phenomenological coefficients. The proposed method factors the interdiffusion coefficient into its two constituent functions. This leads to the existence of non unique solutions and hence yields a set of possible solutions which on an activity-composition diagram exhibit positive and negative deviations from ideality. One additional piece of information, such as the experimentally measured activity at a particular composition or the slope of the Henry's law line at infinite dilution, is needed to select the correct solution. The method successfully predicted the thermodynamics of the CoNi system from calculations bases on the interdiffusion coefficient.     

L-ascorbyl-2-polyphosphate as a vitamin C source for segregated and conventionally weaned pigs

We conducted two experiments to evaluate the efficacy of a stable source of vitamin C for improving performance and iron status in early-weaned pigs. A preparation of L-ascorbyl-2-polyphosphate (Rovimix Stay-C 25, Roche Vitamins, Ames, IA and Bramus, NJ), which supplies 25% ascorbic acid activity in a stable form, served as the vitamin C source and was incorporated at dietary vitamin C levels of 0, 75, or 150 ppm. In Exp. 1, 72 pigs (14 +/- 2 d of age and 4.98 kg BW) were blocked based on initial BW and penned in groups of three (eight pens per treatment) in an off-site nursery for 42 d. Phase 1 lasted from d 0 to 14, Phase 2 from d 14 to 28, and Phase 3 from d 28 to 42 after weaning. Daily gain and gain:feed ratio (G/F) increased during Phase 1 (quadratic, P < .1 and P < .05, respectively), Phase 3 (linear, P < .1 and P < .01, respectively), and for the overall 42-d experiment (linear, P < .05 and P < .1, respectively) in response to increasing dietary vitamin C. At 14 d after weaning, plasma vitamin C increased (linear, P < .05) with increasing dietary vitamin C, but plasma iron, hemoglobin, and hematocrit were not influenced by dietary vitamin C. In Exp. 2, 120 pigs (20 +/- 3 d of age and 7.2 kg BW) were blocked based on initial BW and penned in groups of five (eight pens per treatment) in a conventional nursery system for 31 d. Phase 1 consisted of d 0 to 7, Phase 2 from d 7 to 17, and Phase 3 from d 17 to 31 after weaning. During the period from d 0 to 17 after weaning, ADG and G/F were improved (linear, P < .1) with increasing dietary vitamin C. At d 17 after weaning, plasma vitamin C and serum iron increased (linear, P < .05), but unbound iron-binding capacity and total iron-binding capacity decreased (linear, P < .05 and P < .1, respectively) with increasing dietary vitamin C. These results suggest that dietary vitamin C is needed during the first 42 d after weaning when pigs are weaned as early as 12 d of age and reared in an off-site nursery and during the first 17 d after weaning when pigs are weaned as early as 17 d of age and reared in a conventional nursery system. L-Ascorbyl-2-polyphosphate at a supplemental level of 75 ppm was adequate to meet the dietary vitamin C requirement of early-weaned pigs. Vitamin C supplementation with a stable product will improve performance in young pigs during the high-stress postweaning period and may be particularly beneficial to pigs weaned at a very early age.     

Psychomotor development in children with triphalangeal thumbs. A preliminary study

A double-blind, randomized, clinical field trial was designed to test the efficacy and tolerance of a specific drug treatment in children in the indeterminate phase of infection by Trypanosoma cruzi. Children were treated with benznidazole at a dose of 5 mg/kg/day for 60 days or placebo and followed-up for 48 months. The treated children showed a significant decrease in geometric mean titers of antibodies against T. cruzi measured by indirect hemagglutination, indirect immunofluorescence, and ELISA. After a four year follow-up, 62% of the benznidazole-treated children and no placebo-treated child were seronegative for T. cruzi when tested by an ELISA using a T. cruzi flagellar calcium-binding protein (F29). Xenodiagnosis carried out after 48 months of follow-up was positive in 4.7% of the benznidazole-treated children and in 51.2% of the placebo-treated children. These results show the tolerance to and efficacy of benznidazole against T. cruzi in seropositive children six to 12 years of age. We used an early serologic marker of cure after treatment, consisting of a recombinant antigen implemented in a rapid, conventional serologic procedure.